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Potatoes Can Be Part of a Healthy Diet

Pennington Biomedical Research Center

BATON ROUGE, Louisiana — When we think of healthy vegetables, we don’t think of potatoes, but we should. Potatoes have developed a reputation for causing weight gain and an increased risk for type 2 diabetes, and often find themselves on a list of foods to avoid, especially for individuals with insulin resistance. However, a new study from Pennington Biomedical Research Center, published in the Journal of Medicinal Food, says that potatoes actually did not increase that risk, are filled with key nutrients, and packed with health benefits.

Candida Rebello, PhD, an assistant professor at Pennington Biomedical, served as co-investigator of the study which examined how a diet including potatoes affects key health measures. Rebello, who is also a registered dietitian, said, “We demonstrated that contrary to common belief, potatoes do not negatively impact blood glucose levels. In fact, the individuals who participated in our study lost weight.”

“People tend to eat the same weight of food regardless of calorie content in order to feel full,” Rebello explained. “By eating foods with a heavier weight that are low in calories, you can easily reduce the number of calories you consume. The key aspect of our study is that we did not reduce the portion size of meals but lowered their caloric content by including potatoes. Each participant’s meal was tailored to their personalized caloric needs, yet by replacing some meat content with potato, participants found themselves fuller, quicker, and often did not even finish their meal. In effect, you can lose weight with little effort.”

The study involved 36 participants between the ages of 18 and 60 who were overweight, had obesity, or insulin resistance. Insulin resistance refers to a health condition in which the body’s cells do not respond well to insulin and glucose does not enter into the cells to make energy. Insulin resistance is linked to obesity, high blood pressure, high cholesterol, and type 2 diabetes

Participants were fed precisely-controlled diets of widely available common foods including either beans, peas, and meat or fish, or white potatoes with meat or fish. Both diets were high in fruit and vegetable content and substituted an estimated 40% of typical meat consumption with either beans and peas or potatoes. Previous studies have shown that eating beans and peas improves blood glucose levels in individuals with newly diagnosed type 2 diabetes. To increase the dietary fiber component of the potatoes, they were boiled with the skin intact and then refrigerated between 12 and 24 hours. Potatoes were incorporated into the main lunch and dinner entrées, such as shepherd’s pie and creamy shrimp and potatoes, and served together with sides such as mashed potatoes, oven-roasted potato wedges, potato salad, and scalloped potatoes with lunch and dinner entrees.

“We prepared the potatoes in a way that would maximize their fiber content. When we compared a diet with potatoes to a diet with beans and peas, we found them to be equal in terms of health benefits,” Rebello said. “People typically do not stick with a diet they don’t like or isn’t varied enough. The meal plans provided a variety of dishes, and we showed that a healthy eating plan can have varied options for individuals striving to eat healthy. In addition, potatoes are a fairly inexpensive vegetable to incorporate into a diet.”

Pennington Biomedical Research Center’s Executive Director John Kirwan, PhD, and Principal Investigator on the study said, “Obesity is an incredibly complex disease that Pennington Biomedical is tackling on three different fronts: research that looks at how and why our bodies react the way they do, research that looks at individual responses to diet and physical activity, and policy-level discussions and community programs that bring our research into strategies our local and global communities can use to live healthier lives. These new data on the impact of potatoes on our metabolism is an exciting addition to the arsenal of evidence we have to do just that.”

This work was supported in part by an investigator-initiated grant from the Alliance for Potato Research and Education and in part by a grant from the National Institute on Aging and from the National Institute of General Medical Sciences of the National Institutes of Health, which funds the Louisiana Clinical and Translational Science Center. The funders (Alliance for Potato Research and Education and the National Institutes of Health) had no role in the design, analysis, or writing of the manuscript. The content is solely the responsibility of the authors and does not necessarily represent the official views of the sponsors.

About LSU’s Pennington Biomedical Research Center

The Pennington Biomedical Research Center is at the forefront of medical discovery as it relates to understanding the triggers of obesity, diabetes, cardiovascular disease, cancer and dementia. The Center architected the “Obecity, USA” awareness and advocacy campaign to help solve the obesity epidemic by 2040. The Center conducts basic, clinical, and population research, and is affiliated with Louisiana State University. The research enterprise at Pennington Biomedical includes over 480 employees within a network of 40 clinics and research laboratories, and 13 highly specialized core service facilities. Its scientists and physician/scientists are supported by research trainees, lab technicians, nurses, dietitians, and other support personnel. Pennington Biomedical is located in state-of-the-art research facilities on a 222-acre campus in Baton Rouge, Louisiana. For more information, see https://www.pbrc.edu.

New study finds no association between potato consumption and elevated cardiometabolic disease risk

The latest findings show that overall diet and lifestyle mediate health outcomes associated with potato consumption, not potato preparation methods

Peer-Reviewed Publication

THE ALLIANCE FOR POTATO RESEARCH AND EDUCATION (APRE)

Although potatoes are a nutrient-rich vegetable, they are often singled out as a food to limit. In fact, despite the Dietary Guidelines for Americans’ recommendation to increase fruit and vegetable consumption, some health experts still recommend limiting or avoiding eating potatoes due to concerns that they may increase cardiometabolic risk. However, a newly published study in the Journal of Nutritional Science finds that advice may be unwarranted. Researchers at Boston University examined the influence of potatoes as part of overall diet and lifestyle patterns on cardiometabolic disease risk. They found no change in cardiometabolic risk factors associated with intake of either fried or non-fried potatoes in adults from the long-running Framingham Offspring cohort.

“In this study, we looked at the effects of higher intakes of potatoes on blood pressure, lipids, and glucose and we found that after accounting for other dietary and lifestyle factors, there was no increased risk of cardiometabolic disorders associated with potato consumption,” said lead study investigator Lynn L. Moore, DSc, MPH, associate professor of Medicine at the Boston University Chobanian & Avedisian School of Medicine. “In fact, we found that those in the highest potato intake category consumed 25% more total fruits and vegetables than those in the lower potato intake group. As a result, these participants who consumed more potatoes were more likely to meet the recommendations of the Dietary Guidelines.”

The findings from Moore’s research group observed no association between consuming 4 or more cup-equivalents of potatoes per week (both white and sweet, fried and non-fried) and type 2 diabetes (T2DM), impaired fasting glucose (IFG), hypertension, and dyslipidemia in a large population of healthy Caucasian adults. “We know that potatoes are rich in potassium, magnesium, and dietary fiber, all of which may be protective against the heart attacks and strokes that are a consequence of elevated levels of cardiometabolic risk,” explained Moore. “In fact, potatoes are one of the most important sources of potassium in the American diet.”

Meanwhile, the effects of fried potato consumption appeared to be modified by other diet and lifestyle factors. For example, those with higher intakes of fried potatoes and lower consumption of red meat had a 26% lower risk of elevated triglycerides. Additionally, more physically active adults who consumed higher levels of fried potatoes had a 25% lower risk of developing Type 2 diabetes. These findings underscore the importance of overall diet and lifestyle when it comes to cardiometabolic disease risk,” Moore added. “Public health messaging singling out potatoes, and even fried potatoes, is not supported by this evidence.”

These study results indicate that potatoes, both fried and non-fried sweet and white potato varieties, can be included as part of a healthy diet without impacting risk factors for cardiometabolic disease. Further, potatoes contribute to total fruit and vegetable intake, thus enabling consumers to more closely align with the Dietary Guidelines recommendations.

As Moore explained, “Previously published evidence on potato consumption has been conflicting. For example, some find higher potato intakes to be positively associated with elevated blood pressure while others find the opposite. In observational studies, it is important to try to separate out a food like potatoes from other dietary components. If the individuals consuming more potatoes, for example, also consume more refined grains or have other unhealthy lifestyle habits, then the adverse effect of potatoes may actually be a result of other things associated with diet and lifestyle.”

One strength of the current study is that diet was assessed with detailed dietary records, thus allowing the investigators to determine cooking methods. In addition, dietary records provide a more accurate assessment of the intake of most foods and nutrients than the food frequency questionnaires that have been used in many other studies.

The results of this study support the need for future randomized controlled trials to investigate the effects of potatoes as part of a healthy diet (including potatoes cooked in different ways) on cardiometabolic disease risk. In the interim, these data add to the evidence supporting a role for potatoes as part of a healthy lifestyle.

Study Design, Strengths, and Limitations 

Data from 2,523 offspring of the Framingham Heart Study, 30 years of age and older, were included in this prospective cohort study that began in 1971.

  • Approximately 16,000 collective days of dietary records were collected from roughly 70% of participants during exams 3 (1983-87) and 5 (1991-95).
  • The consumption of potatoes (both white and sweet potatoes) was derived from total vegetable servings. For these analyses, each participant’s usual potato intake was estimated as the mean from all days of diet records and grouped as follows: total potato intake (<1, 1-<2, 2-<4, and ≥4 cup-equivalents/week, and fried or non-fried (<1, 1-<2, and ≥2 cup-equivalents/week).
  • Health outcome data were provided from regular examination visits.
  • Researchers assessed the impact of both total potato consumption as well as fried versus non-fried potato consumption on hypertension, T2DM/IFG, and dyslipidemia risk.
  • Researchers further assessed whether other diet and lifestyle factors modified the effects of fried and non-fried potato intakes on cardiometabolic risk.

In addition to the large sample size, the use of a prospective study design allowed for the assessment of large amounts of data from subjects in a free-living environment. For example, potato consumption was averaged over 8 years before the beginning of a 16-year follow-up. Furthermore, dietary intake was analyzed from an average of 6 days of dietary records, thus providing a more stable intake assessment. Further studies will need to assess more diverse populations, as this current sample of Caucasian adults is not broadly generalizable. Future studies will also benefit from consideration of cooking methods and by studying the specific effects of potatoes when consumed as part of a healthy diet.

This research was supported by the Alliance for Potato Research and Education (APRE). APRE had no influence on the study design, conduct, execution, or data analysis after approving the initial proposal for funding.

The article “Potato Consumption is not Associated with Cardiometabolic Health Outcomes in Framingham Offspring Study Adults” is published in the Journal of Nutritional Science (doi: 10.1017/jns.2022.65).

Journal: Journal of Nutritional Science

DOI: 10.1017/jns.2022.65

Article title: Potato Consumption is not Associated with Cardiometabolic Health Outcomes in Framingham Offspring Study Adults

Article publication date: 09/02/2022


JOURNAL

Journal of Nutritional Science

DOI

10.1017/jns.2022.65 

ARTICLE TITLE

Potato consumption is not associated with cardiometabolic health outcomes in Framingham Offspring Study adults

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New study illustrates that potato protein ingestion strongly increases muscle protein synthesis rates at rest and during recovery from exercise

The latest findings challenge outdated assumptions about the anabolic effects of plant-derived proteins

Peer-Reviewed Publication

THE ALLIANCE FOR POTATO RESEARCH AND EDUCATION (APRE)

Exercise enthusiasts have long presumed animal protein to be superior to plant-derived options for muscle protein synthesis due to its essential amino acid profile. While many plant proteins are deficient in one or more essential amino acids necessary for optimal muscle growth and repair, a new randomized controlled study published in Medicine & Science in Sports & Exercise shows that plant-derived proteins can still induce strong anabolic responses. Researchers at Maastricht University, The Netherlands, found that consuming 30 grams of potato-derived protein concentrate following resistance exercise strongly increased muscle protein synthesis rates to levels that did not differ from the response following the ingestion of an equivalent amount of milk protein concentrate.

“The anabolic response to exercise depends on the exercise stimulus and the postprandial increases in circulating amino acids,” said lead study investigator Luc J.C. van Loon, PhD, a professor of physiology of exercise and nutrition at Maastricht University Medical Centre. “In general, plant-derived proteins are considered to have lesser anabolic properties, due to their lower digestibility and incomplete amino acid profile. Our results show that ingestion of 30 g potato-derived protein will support muscle growth and repair at rest and during recovery from exercise.”  

The findings from van Loon’s research group demonstrate that potato-derived protein concentrate powder can be used to increase muscle protein synthesis rates both at rest and during post-exercise recovery in healthy, young men, at rates that do not differ from the ingestion of an equivalent amount of milk protein.

“The potato’s amino acid profile has no apparent deficiencies and ingestion of 30 g protein was shown to strongly stimulate muscle protein synthesis during recovery from exercise,” explained van Loon.

These study results are part of a growing body of literature that demonstrate the benefits of potatoes in physical activity and exercise recovery.1-3 As van Loon explained, “Although further dose-response studies in broader populations are undoubtedly necessary, these data seem to support the use of potato-derived protein concentrate as an effective means to support muscle conditioning.”

Study Design, Strengths, and Limitations 

Twenty-four young, healthy males between the ages of 20-28 years volunteered to participate in this randomized, double blind, parallel group study.

  • Participants completed resistance exercise on a seated knee-extension machine (randomized to complete with either their dominant or non-dominant leg) following a warm-up on a supine leg press machine.
  • Participants rested for 10 minutes following their exercise session. Blood samples were drawn, and muscle biopsies were taken from each leg.
  • Immediately after the biopsies, 12 participants ingested 30 grams potato-derived protein while the other 12 ingested an equivalent amount of milk-derived protein. 
  • Blood samples were collected over a 5-hour period following ingestion to determine blood amino acid, glucose, and insulin concentrations.
  • Second and third muscle biopsies were taken to determine muscle protein synthesis rates at rest and during recovery from exercise.

The strategic use of a randomized double-blind study design with a unilateral exercise protocol allowed for assessment of postprandial muscle protein synthesis in both exercised and non-exercised muscle. Further studies will need to assess dose-response relationships between smaller and larger doses of protein on muscle protein synthesis. Future studies will also benefit from assessing the effects of plant-derived protein concentrates on muscle conditioning after repeated bouts of exercise in larger and more diverse populations.

Nonetheless, the current data show “there is ample room for high quality plant-derived proteins in sports nutrition, such as protein from nutrient-dense sources like potatoes,” stated van Loon.

This research was supported by the Alliance for Potato Research and Education (APRE). APRE had no influence on the study design, conduct, execution, or data analysis after approving the initial proposal for funding.

The article “Potato Protein Ingestion Increases Muscle Protein Synthesis Rates at Rest and during Recovery from Exercise in Humans” is published in Medicine & Science in Sports & Exercise (10.1249/MSS.0000000000002937).

References

  1. Oikawa SY, Bahniwal R, Holloway TM, Lim C, McLeod JC, McGlory C, Baker SK, Phillips SM. Potato Protein Isolate Stimulates Muscle Protein Synthesis at Rest and with Resistance Exercise in Young Women. Nutrients. 2020 Apr 27;12(5):1235. doi: 10.3390/nu12051235.
  2. Flynn S, Rosales A, Hailes W, Ruby B. Males and Females Exhibit Similar Muscle Glycogen Recovery with Varied Recovery Food Sources. Eur J Appl Physiol. 2020. doi: 10.1007/s00421-020-04352-2
  3. Salvador AF, McKenna CF, Alamilla RA, et al. Potato Ingestion is as Effective as Carbohydrate Gels to Support Prolonged Cycling Performance. J Appl Physiol. 2019;127(6):1651-1659. doi: 10.1152/japplphysiol.00567.2019

DOI

10.1249/MSS.0000000000002937 

METHOD OF RESEARCH

Randomized controlled/clinical trial

SUBJECT OF RESEARCH

People

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New nutrient profiling tools confirm starchy vegetables deliver comparable nutritional value as non-starchy vegetables and whole fruit

Peer-Reviewed Publication

THE ALLIANCE FOR POTATO RESEARCH AND EDUCATION (APRE)

A new study recently published in Frontiers in Nutrition has challenged the tendency in nutrition research to separate starchy vegetables from their non-starchy counterparts and categorize them with foods delivering lower nutritional value.

Whole grains, legumes, non-starchy vegetables, and fresh fruit are typically considered to be higher quality carbohydrate foods, yet starchy vegetables, including white potatoes, are typically categorized in nutrition studies with sweets, candy, and soda, when researchers assess subjects’ food intake and associations with health outcomes. This new study used five separate indices to assess carbohydrate quality to determine if this categorization of starchy vegetables is an accurate reflection of the foods’ nutritional value.

Four of those carbohydrate quality indices (CQIs), based on carbohydrate to fiber and sugar ratios, had been developed and validated in 2021 by researchers at Tufts University. The fifth index, the new carbohydrate food quality scoring system (CFQS-4) recently developed by scientists working with the Quality Carbohydrate Coalition, also incorporated potassium and sodium. All five indices had been previously published.

The new study screened more than 2,400 carbohydrate-containing foods for carbohydrate quality.  Recognizing that carbohydrates are present in a great variety of plant-based foods, the study expanded the range of food groups to include refined and whole grains, snacks and sweets, but also starchy and non-starchy vegetables, legumes and whole fruit. Starchy vegetables had not been tested before using the new carbohydrate quality metrics.

“Starchy vegetables are often not even viewed as vegetables and are routinely removed from high-quality food categories in nutrition research. That view is now challenged by the new nutrient profiling methods” said lead author Adam Drewnowski, PhD, researcher at the Center for Public Health Nutrition at the University of Washington. “Now that we have formal measures of carbohydrate quality that we can agree on, it is time to put starchy vegetables back where they belong.  There is no need to demonize ‘bad’ vegetables when the American diet could do with more produce of all kinds.”

“I certainly hope that the Dietary Guidelines Advisory Committee take note as they design a healthy diet at an affordable cost,” Dr. Drewnowski added

The four CQIs and the CFQS-4 had been published before but had not been applied to evaluating carbohydrate quality of legumes, vegetables and fruit.  The five indices were based on specific rations of carbohydrate, fiber, free sugar, potassium and sodium. Whereas potassium is under-consumed, sodium is consumed to excess. Both nutrients are recognized as ‘nutrients of public health concern’ in the Dietary Guidelines for Americans.

Based on the four CQI scores, nearly half of the 210 starchy vegetable foods analyzed in the study met the CQI definitions for high-quality carbohydrates, which were defined as those with evidence-based cut-off values for fiber and free sugar. Meanwhile, extremely few snacks and sweets (1-5%), candy and desserts (0-5%) and refined grain foods (10-12%) could be considered high-quality, according to the same CQI measures.

Based on the more comprehensive CFQS-4 model, which also accounts for foods’ potassium and sodium content, starchy vegetables scored most closely to non-starchy vegetables and fruit versus sweets and soda.

“I hope that this simple application of existing carbohydrate quality metrics to a wide spectrum of carb-containing foods will show that starchy vegetables belong with the high-quality carbohydrate foods” said Drewnowski. “Our application of other nutrient profiling has previously shown that potatoes and beans led the pack in terms of nutrients per penny. This latest demonstration clearly shows that all vegetables should remain together when it comes to both research and dietary guidance.”

Study Design, Strengths, and Limitations

More than 2,400 carbohydrate foods in the USDA Food and Nutrient Database for Dietary Studies were evaluated using four previously published CQIs, and one more recently created carbohydrate food quality scoring system (CFQS-4).

Specifically, the various CQI composites were:

  • 10:1 Carbohydrate-to-Fiber model: at least 1 gram of fiber for every 10 grams of carbohydrate
  • 10:1:1 Carbohydrate-to-Fiber-to-Free Sugars model: at least 1 gram of fiber and no more than 1 gram of free sugar for every 10 grams of carbohydrate 
  • 10:1:2 Carbohydrate-to-Fiber-to-Free Sugars model: at least 1 gram of fiber and no more than 2 grams of free sugar for every 10 grams of carbohydrate
  • 10:1|2:1 Carbohydrate-to-Fiber and Sugar-to-Fiber model: at least 1 gram of fiber for every 10 grams of carbohydrate and fewer than 2 grams of sugar per 1 gram of fiber
  • The CFQS-4 model builds upon previous 10:1 and 10:1:1 ratios for fiber and free sugars relative to carbohydrate, but also assesses sodium (an over-consumed nutrient of concern) and potassium content (a shortfall nutrient of concern) according to the Dietary Guidelines for Americans.

Foods with at least 40% energy from carbohydrates per 100g dry weight were included in all analyses. The frequency and percentage of foods that met the CQI criteria were calculated for each food group. Carbohydrate quality scores were measured against the average energy densities of food groups and subgroups.

This study included a large, comprehensive data set using multiple nutrient profiling models. Further research to build upon these models, however, should continue to incorporate other vitamins and minerals in food quality assessments. Nonetheless, this study aligns with a broader, evolving body of literature showcasing the multi-dimensionality of carbohydrate foods and their role in human health. As Dr. Drewnowski explained, “Current efforts to inform dietary guidelines and regulatory frameworks would benefit from modern, comprehensive tools to define and assess carbohydrate food quality.”

This research was supported by the Alliance for Potato Research and Education (APRE) and by the Quality Carbohydrate Coalition (QCC), which is funded by Potatoes USA. Neither APRE nor Potatoes USA had an influence on the study design, conduct, execution, or data analysis after approving the initial proposal for funding. Dr. Adam Drewnowski is a member of the QCC-Scientific Advisory Council.

The article “Multiple metrics of carbohydrate quality place starchy vegetables alongside non-starchy vegetables, legumes, and whole fruit” is published in Frontiers in Nutrition (doi: 10.3389/fnut.2022.867378).


JOURNAL

Frontiers in Nutrition

DOI

10.3389/fnut.2022.867378 

Read the Full Study Summary

The glycemic index may be counterproductive to helping Americans adopt healthier diets

Newly published perspective examines the shortcomings of the glycemic index as a measure of carbohydrate food quality

Peer-Reviewed Publication

THE ALLIANCE FOR POTATO RESEARCH AND EDUCATION (APRE)

Today, many people struggle to make healthy food and beverage choices in line with the Dietary Guidelines for Americans (DGA). In fact, the average American under-consumes nutrient-dense fruits, vegetables, whole grains, beans and dairy foods – and more than half of American adults have at least one diet-related chronic disease.1 To improve overall diet quality, Jill Nicholls, PhD, asserts in a recently published perspective in Frontiers in Nutritionpeople need tools that are relevant, reliable and applicable – and evidence suggests the glycemic index (GI) falls short on all of the above.

“The GI is increasingly used and interpreted as a measure of overall carbohydrate food quality, with some proponents advocating for its broader adoption as a public health tool. However, the GI model doesn’t address nutrient density or translate well to healthy dietary patterns, and its narrow focus on just one dimension of carbohydrate-containing foods may divert public attention away from approaches to improving health that are accessible, affordable, culturally appropriate and environmentally sustainable,” stated Nicholls, owner of Food Context, LLC. “At best, it’s an incomplete gauge of carbohydrate food quality. At worst, it may be counterproductive to achieving the dietary recommendations set forth in the DGA.”

Intended for People with Type 1 Diabetes – Not the General Public

Developed in the 1980s as a blood glucose management tool for people with type 1 diabetes, the GI is a comparative measure of glycemic impact. The GI measures the ability of the available carbohydrate in a food to increase blood glucose. It is determined by measuring blood glucose after consuming 50 grams of carbohydrate from a single test food and normalizing to a comparable portion of a control food, typically pure glucose or white bread.2

Carbohydrate-containing foods are quite varied and make important contributions to dietary patterns, yet the GI measures only glucose response. It does not account for overall nutrient content, and research has shown it may not be an accurate predictor of overall diet quality. And because low-GI foods are not necessarily high in essential nutrients, over-reliance on GI values may lead to food choices that are inconsistent with current dietary guidelines. Energy-dense choices such as ice cream and candy bars, for instance, can have low GI values, while nutrient-dense choices that support healthy dietary patterns can also be high-GI foods, including carrots, potatoes and grains.

An Unreliable and Highly Individualized Measure of Glycemic Response

“The reliability of the GI has been scrutinized since its introduction more than 40 years ago, including critiques about methodology and questions about the relationship between a food’s GI value and true post-meal glycemic response,” said Nicholls.

Because GI values are calculated based on foods consumed in isolation and analyzed under standard laboratory conditions, their real-world application may be limited. “Under the GI model, fat, protein and fiber are treated as entirely independent variables, but that assumption is at odds with current views about our understanding of how eating patterns influence health based on all food and beverage contributions,” Nicholls explained.

Much of the research has demonstrated significant variability in both inter- and intra-individual glycemic responses to the same food. Thus, it remains unclear whether the GI is a property of foods or a characteristic of each unique individual consuming those foods. Emerging studies have found that glycemic responses are more similar within individuals than between them, and an array of factors in addition to meal composition can influence individual carbohydrate metabolism, including, meal timing, physical activity and sleep habits. 4

A Questionable Predictor of Health Outcomes

Research also indicates that the GI may not be the best carbohydrate food quality metric to assess diets and chronic disease prevention. In a landmark series of systematic reviews and meta-analyses, Reynolds et al. found that the association between the GI and risk of non-communicable diseases was low to very low compared to fiber or whole grains.5 Meanwhile, the dietary patterns emphasized in the DGA contain more whole grains and fiber-containing foods than Americans usually eat, along with higher amounts of fruits, vegetables, and dairy foods. These patterns are associated with lower risk for NCDs. Eating nutrient-dense whole foods as part of balanced meals during the day is an easy way to improve glycemic responses and improve diet quality without monitoring the GI of foods.

“The Mediterranean Diet is one example of a dietary pattern that has been associated with reduced disease risk; yet, not every food in a Mediterranean eating pattern is low GI,” Nicholls added. In addition, clinical trials have shown compelling evidence that high GI foods eaten within the context of high-quality dietary patterns can yield improvements in cardiovascular disease risk factors, and weight loss regimens may be less reliant on glycemic responses than expected.6-7

“Evidence increasingly suggests that it’s the total diet that counts. Improving the overall quality of an individual’s dietary patterns can have beneficial effects on a variety of diet-related chronic disease, but the effect of any single food choice is mediated by the other foods and beverages eaten, physical activity and other lifestyle choices. While the GI may illuminate some narrow insights, it also keeps many of these relevant variables in the dark.”

The article, “Perspective: The Glycemic Index Falls Short as a Carbohydrate Food Quality Indicator to Improve Diet Quality,” is published in Frontiers in Nutrition (https://doi.org/10.3389/fnut.2022.896333). Funding was provided by the Alliance for Potato Research and Education.

References:

1U.S. Department of Agriculture and U.S. Department of Health and Human Services. Dietary Guidelines for Americans, 2020-2025. 9th Edition. December 2020. [Internet]. Available from: https://www.dietaryguidelines.gov/sites/default/files/2020-12/Dietary_Guidelines_for_Americans_2020-2025.pdf

2Wolever, T.M., Jenkins, D.J., Jenkins, A.L., & Josse, R.G. (1991). The glycemic index: methodology and clinical implications. The American journal of clinical nutrition, 54 5, 846-54

3Zazpe, I., Sánchez-Taínta, A., Santiago, S., De la Fuente-Arrillaga, C., Bes-Rastrollo, M., Martínez, J., & Martínez-González, M. (2014). Association between dietary carbohydrate intake quality and micronutrient intake adequacy in a Mediterranean cohort: The SUN (Seguimiento Universidad de Navarra) Project. British Journal of Nutrition, 111(11), 2000-2009. doi:10.1017/S0007114513004364

4Berry SE, Valdes AM, Drew DA, Asnicar F, Mazidi M, Wolf J, et al, Human postprandial responses to food and potential for precision nutrition. Nat Med. (2020) 26:964–73. doi: 10.1038/s41591-020-0934-0

5Reynolds A, Mann J, Cummings J, Winter N, Mete E, Te Morenga L. Carbohydrate quality and human health: a series of systematic reviews and meta-analyses. Lancet. (2019) 393:434–45. doi: 10.1016/S0140-6736(18)31809-9

6Sacks FM, Carey VJ, Anderson CAM, Miller ER III, Copeland T, Charleston J, et al. Effects of high vs. low glycemic index of dietary carbohydrate on cardiovascular disease risk factors and insulin sensitivity: the OmniCarb randomized clinical trial. J Am Med Assoc. (2014) 312:2531–41. doi: 10.1001/jama.2014.16658

7Gardner CD, Trepanowski JF, Del Gobbo LC, Hauser ME, Rigdon J, Ioannidis JPA, et al. Effect of low-fat vs. low-carbohydrate diet on 12-month weight loss in overweight adults and the association with genotype pattern or insulin secretion: the DIETFITS randomized clinical trial. J Am Med Assoc. (2018) 319:667–79. doi: 10.1001/jama.2018.0245


DOI

10.3389/fnut.2022.896333 

Read the Full Study Summary

Clarifying carb confusion: experts propose evidence-based scoring system to assess the overall healthfulness of carb-containing foods

New ‘Carbohydrate Food Quality Score’ considers a comprehensive and practical approach, aligning with the Dietary Guidelines for Americans

Peer-Reviewed Publication

THE ALLIANCE FOR POTATO RESEARCH AND EDUCATION (APRE)

April 11, 2022 – The dietary value of carbohydrate foods (CF) has come under increased scrutiny in recent years. While so-called good-carb/bad-carb designations are hotly contested, standardized methods for assessing CF health quality currently do not exist. In a paper recently published in Nutrientsthe Quality Carbohydrate Coalition-Scientific Advisory Council (QCC-SAC) proposes a novel, innovative approach to quantifying CF quality: the Carbohydrate Food Quality Score (CFQS). Representing a significant step forward in the evolution of CF analysis, the new CFQS incorporates a food’s fiber-to-carbohydrate and free sugar-to-carbohydrate ratios, as previous metrics have done, in addition to evaluating its sodium, potassium and (as applicable) whole grain content, making the index better reflect the nutritional contribution of the entire CF.

“While long-standing evidence clearly establishes that carbohydrate-containing foods are essential to building healthy dietary patterns, people need better tools to identify higher quality choices that can be balanced in a healthy dietary pattern,” said Joanne Slavin, PhD, RD, University of Minnesota. “While fiber and sugar content have been the focus in previously proposed systems, and they’re important pieces of the puzzle, there needs to be more nuance in our recommendations given the breadth of foods and food groups that fall into the carb category.” Slavin is a member of the QCC-SAC, which was formed by Potatoes USA and other commodity group stakeholders that comprise the Coalition.

To provide a more complete appraisal of CF quality – and to reflect the most up-to-date dietary guidance – the new carbohydrate quality scoring system is the first of its kind to include an assessment of sodium, potassium and whole grain content in addition to sugar and fiber. These three components were added because CFs are predominant dietary sources of these nutrients. Sodium, like sugar, is consumed at levels above those recommended in current dietary guidance, and potassium and whole grains, like dietary fiber, are consumed at levels well below those recommended. By including all these components, this approach not only aligns with the recommendations of the 2020-2025 Dietary Guidelines for Americans (DGA), but also the World Health Organization, and roughly half of the food-based dietary guidelines from around the world.

“Other systems to define carb quality exist, and many rely heavily on the glycemic index; however, research increasingly shows GI has far too much inter-individual variability to offer meaningful real-world utility,” noted QCC-SAC member Siddhartha Angadi, PhD, University of Virginia. “A truly effective measure of carbohydrate food quality is one that is both accurate and practical. By capturing a broader set of dietary parameters with relevance to public health, the CFQS aims to offer relevant, real-world recommendations to potentially improve nutrient intake and public health.”

The new system builds upon previously validated measures of CF quality, namely ratios of carbohydrate to fiber (i.e., at least one gram of fiber for every 10 grams of carbohydrate) and carbohydrate to free sugar (i.e., less than one gram of free sugar for every 10 grams of carbohydrate). The addition of potassium, sodium and whole grains to the algorithm was further validated by demonstrating a high correlation with two other scientifically substantiated nutrient profiling systems: the Nutrient Rich Food (NRF9.3) index, an algorithm for assessing a food’s nutrient density, and Nutri-Score, a European model used to assess foods’ nutritional value.

“The high degree of agreement between the CFQS models and these other established metrics further support the efficacy of our approach,” explained Adam Drewnowski, PhD, University of Washington, a QCC-SAC member and creator of the NRF9.3 index. “We can say with great confidence that the CFQS is assessing the quality of carbohydrate foods in an accurate and meaningful way.”

The Carbohydrate Food Quality Score: How It Works

So far, two models have been developed using the new scoring system. One model, known as the CFQS-4, assigns a score of zero to four points to all carbohydrate-containing foods, which in this study were defined as solid foods with ≥ 40% energy from carbohydrate (as measured by 100g dry weight). The more advanced model, known as the CFQS-5, assigns a score of zero to five points, in which grain foods can score an extra point if their whole-grain content is ≥25%, which was selected as the cutoff value based on previous studies and current U.S. front-of-pack regulations.

In the CFQS-4 model:

  • 1 point is awarded if fiber is ≥10g/100g carb portion
  • 1 point if free sugar is <10g/100g carb portion
  • 1 point if sodium is <600mg/100g dry weight
  • 1 point if K >300mg/100g dry weight

In the CFQS-5 model for grain-based foods, one additional point is awarded for whole grain content:

  • 1 additional point if whole grains ≥25g/100g dry weight

“This system is already much more comprehensive than previously published metrics, but it’s also designed to continue evolving with the science,” said Drewnowski. “As new data become available, the CFQS models can expand to reflect other measures of carbohydrate quality, such as the food’s prebiotic or polyphenol composition, degree of processing or aspects of fortification or enrichment.”

This report builds on an earlier QCC-SAC publication from July 2021, which reviewed the current state of CF quality metrics and established initial guiding principles for developing a new scoring metric for determining CF quality. The latest report advances this work by introducing a more broadly applicable Carbohydrate Food Quality Score and comparing it to other measures of nutrient density.

As a next step, the researchers are preparing a paper demonstrating how the new scoring system can be applied to a variety of eating patterns.

“We need tools that help people apply nutrition science to an array of cultural dietary traditions, socioeconomic contexts and personal needs and preferences,” added QCC-SAC member Judith Rodriguez, PhD, RD, University of North Florida. “That’s the ultimate aim of this work: to develop a metric that can be applied to build healthy dietary patterns for everyone.”

#### 

The Quality Carbohydrate Coalition (QCC) is a multi-stakeholder engagement of commodity groups across the food industry. Guided by the work of its Scientific Advisory Council (SAC), this group aims to support a collaborative, scientific dialogue around the unique and diverse roles that carbohydrate-containing foods play in healthful eating.  The council is made up of six world-renowned experts in carbohydrate research, nutrient profiling, cultural competency and epidemiology: Adam Drewnowski, PhD; Julie Miller Jones, PhD, LN, CNS; Judith Rodriguez, PhD, RD; Joanne Slavin, PhD, RD; Siddhartha Angadi, PhD; and Yanni Papanikolaou, MPH.  Potatoes USA provides the funding to support the research being conducted by the SAC.

The article, “A New Carbohydrate Food Quality Score to Reflect Dietary Guidelines: An Expert Panel Report,” is published in Nutrients (doi: 10.3390/nu14071485). All QCC-SAC members were authors, supported by Kevin Comerford, PhD. Funding was provided by Potatoes USA.


JOURNAL

Nutrients

DOI

10.3390/nu14071485 

ARTICLE TITLE

A New Carbohydrate Food Quality Scoring System to Reflect Dietary Guidelines: An Expert Panel Report

ARTICLE PUBLICATION DATE

28-Mar-2022

Read the Full Study Summary

Which promote greater metabolic health, almonds or potatoes? Rigorous, randomized trial weighs in

No short-term, statistically significant difference between calorie-matched fries and almonds on key health metrics

Peer-Reviewed Publication

THE ALLIANCE FOR POTATO RESEARCH AND EDUCATION (APRE)

March 7, 2022 — White potatoes — especially French fries — are often described in nutrition research literature and dietary guidance statements as having associations with obesogenic diets and as increasing chronic disease risk based on observational research findings. However, there is limited evidence from randomized controlled trials (RCTs) testing cause-and-effect relationships. Now, an RCT published in the American Journal of Clinical Nutrition demonstrates that adding a 300-calorie serving of French fries to one’s typical diet every day for a month does not result in differential weight gain or other biomarker changes associated with impaired blood sugar regulation compared to adding an isocaloric daily serving of almonds, generally considered a healthy snack option.

“In our School of Public Health at Indiana University-Bloomington and in my own work, we adhere to a slogan: ‘It’s About Knowing.’ Because conjecture is good, but knowing is better,” says David Allison, PhD, the study’s principal investigator. “The way we come to know is through rigorous, randomized controlled trials. Based on our RCT findings, there is no statistically significant evidence of differential effects between consuming a typical 300-calorie serving of French fries daily and a 300-calorie serving of almonds daily when it comes to weight gain or markers of type 2 diabetes risk, at least in the short term.”

Changes in body composition (i.e., body fat mass), body weight, fasting glucose and fasting insulin levels at the end of the one-month trial were comparable across the French fry and almond intervention groups and were not clinically significant. As expected, given the difference in carbohydrate content between the French fries and almonds, acute peak blood glucose and insulin levels were higher after consuming the French fries. However, these levels were not elevated beyond a normal range, and this difference did not have an apparent impact on any other glucoregulatory biomarkers.

“Our results show two food items identified previously for opposite associations with health outcomes had no differences in effects on the health outcomes we measured,” notes study co-author Daniel Smith, PhD. “Nutrition recommendations that focus primarily on single foods in isolation may be missing the mark. A more effective approach to dietary guidance is likely one that takes total diet, lifestyle and individual needs and risk factors into account.”

Study Design, Strengths, and Limitations

A group of 180 adult men and women were randomized to one of three treatment groups for 30 days, with 165 completing the study. The three arms included an additional 300 kilocalories/day from one of the three food items (below) and participants were asked to add the specific food item into their “normal daily diet.”

  • Almonds: approximately 1/3 of a cup of almonds, roasted and salted
  • Standard French fries: approximately the size of a medium serving
  • French fries with herb/spice mix: approximately the size of a medium serving, prepared with oregano, basil, garlic, onion and rosemary

Instructions were provided regarding storage and preparation methods of food items for all participants. Participants were simply asked to incorporate the specific food item into their normal daily diet. They were not instructed to compensate for these added calories in any way.

Body composition (body fat mass), body weight, blood sugar, insulin and hemoglobin A1c were measured at baseline and at study completion. A subset of five participants also completed post-meal evaluations to assess short-term blood sugar response.

The study’s strengths include its randomized controlled trial design, considered the gold standard in identifying causal relationships, as well as the standardization of the study foods’ preparation, presentation and convenience. Its limitations include the fact that it was a free-living study, limiting researchers’ control over the participants’ diets; however, such a study design also allows for real-world data collection. It also excluded participants with type 2 diabetes, limiting the application of the findings to individuals without the disease. Additionally, the study did not include an analysis of energy (calorie) intake, nor were satiety data collected, making it unclear exactly how the varied snack intakes affected calorie intake overall.

The research article, “French-fried potatoes consumption and energy balance: a randomized controlled trial,” is published in The American Journal of Clinical Nutrition (https://doi.org/10.1093/ajcn/nqac045). Authors include David Allison, PhD, Indiana University and Daniel Smith, PhD, University of Alabama at Birmingham. Funding was provided by the Alliance for Potato Research and Education; however, APRE had no influence on the study design, conduct, execution or data analysis after approving the initial proposal for funding.


JOURNAL

American Journal of Clinical Nutrition

DOI

10.1093/ajcn/nqac045 

METHOD OF RESEARCH

Randomized controlled/clinical trial

SUBJECT OF RESEARCH

People

ARTICLE TITLE

French-fried potatoes consumption and energy balance: a randomized controlled trial

ARTICLE PUBLICATION DATE

18-Feb-2022

Read the Full Study Summary

New study finds potatoes, when enjoyed as part of a healthy diet, are not associated with elevated heart health risk factors among adolescent girls

Eating potatoes also linked to improved nutrient intakes in ‘tween’ girls

Peer-reviewed Publication

THE ALLIANCE FOR POTATO RESEARCH AND EDUCATION (APRE)

NEWS RELEASE 27-OCT-2021

Adolescence is a critical period for the evolution of cardiometabolic risk factors that are largely influenced by diet and lifestyle. Understanding these risk factors is essential to developing effective dietary guidance for disease prevention targeting this critical age period. Recently published research in the British Journal of Nutrition found that 9-17 year-old girls who consumed up to one cup of potatoes daily had no increased risk of becoming overweight or developing high blood pressure, dyslipidemia, or impaired fasting glucose by the end of the study in late adolescence.

According to the 2020-2025 Dietary Guidelines for Americans, girls aged 9 – 18 are encouraged to consume 1½ to 3-cup equivalents per day of vegetables, depending on their calorie needs, but most fail to meet these guidelines. In this study, the highest levels of potato consumption ranged from 1/5 to 1 cup per day and at that level, no adverse effects were observed.

“Our results show that nutrient-rich potatoes can be part of a healthy diet in young girls during this important period of growth and development,” says Lynn L. Moore, DSc, MPH, Boston University, the study’s senior author. “There is growing evidence that overall diet quality is what really matters in the preservation of heart health. Potatoes are an affordable food, with a number of valuable nutrients, and our research suggests that moderate intakes of potatoes, along with many other types of vegetables,  can be a regular part of a healthy diet pattern.”

Higher intakes of all forms of potatoes (including fried) during the ‘tween’ years of nine to 11 were associated with higher intakes of potassium and dietary fiber, two nutrients of public health concern, [i]   as well as vitamin C, vitamin B6 and magnesium. Black girls in this study with the highest intakes of potatoes also consumed more fruit and non-starchy vegetables and had higher diet-quality scores.

Study Design, Strengths and Limitations

The researchers analyzed data from nearly 2,000 subjects (approximately 50% Black, 50% White) from the National Growth and Health Study, a longitudinal study of the development of obesity and other cardiovascular-related outcomes in adolescent girls.

  • For girls at 9-11 years of age, researchers analyzed data on total potato intake (white and sweet) as well as separate intakes of fried and non-fried potatoes.
  • For girls at 9-17 years of age, researchers analyzed data for total potato intake (white and sweet).

Diet was assessed using 3-day diet records at baseline when girls were 9-10 years old, and during the follow-up years 2-5, 7, 8, and 10. The intake of potatoes (both white and sweet potatoes) was extracted from total vegetable servings. Anthropometric measures of body fat and body composition and blood pressure were measured annually. Additionally, fasting triglycerides, other lipids, and glucose were measured in later adolescence (at 18-20 years of age)

Repeated measures of a number of potential confounding variables were examined, including socioeconomic status, body mass index (BMI), changes in height, physical activity, television viewing, intakes of food groups and nutrients, as well as diet quality measured by the Healthy Eating Index (HEI)-2015. The study’s strengths include its prospective design as well as the use of multiple sets of three-day diet records, which is considered the gold standard method for dietary assessment. Researchers also took repeated measures of cardiometabolic risk factors and most potential confounders.

The investigators acknowledge limitations to the study, such as reliance on self-reported dietary intakes from adolescents who may have had difficulty accurately estimating portion sizes and reporting details. However, parents and other caregivers were actively involved in the completion of these diet records, especially during the earlier years of the study. Researchers were unable to assess the effects of very high levels of potato intakes since few girls reported consuming more than one cup equivalent of potatoes per day. They were also unable to analyze any differences between white and sweet potato consumption, given the low intakes of sweet potatoes within the study population. Finally, the researchers were unable to control for baseline values of fasting glucose or triglycerides due to missing or unreliable data at the initial exam.

This study was selected as the Nutrition Society’s Paper of the Month. Every month, the Editors-in-Chief of the Nutrition Society’s journals select one paper as being of particular interest or originality, and/or because it challenges previously conceived notions in nutritional science and public health. The research manuscript, “Potato consumption is not associated with elevated cardiometabolic risk in adolescent girls,” is published in the British Journal of Nutrition (https://doi.org/10.1017/S0007114521003445). Authors include Ioanna Yiannakou, Mengjie Yuan, R. Taylor Pickering, Martha R. Singer, and Lynn L. Moore, Boston University. In addition to funding from the National Institutes of Health, funding was provided by the Alliance for Potato Research and Education (APRE); APRE had no input on interpretation of the results or manuscript development.


[i] U.S. Department of Agriculture and U.S. Department of Health and Human Services. Dietary Guidelines for Americans, 2020-2025. 9th Edition. December 2020. Available online: https://DietaryGuidelines.gov


JOURNAL

British Journal Of Nutrition

DOI

10.1017/S0007114521003445 

ARTICLE TITLE

Potato consumption is not associated with elevated cardiometabolic risk in adolescent girls

ARTICLE PUBLICATION DATE

6-Sep-2021

Read the Full Study Summary

Shifting the dialogue on high-quality carbohydrate foods

Experts propose a nuanced approach to define high-quality carbohydrate foods while avoiding unreliable indicators, like GI

Peer-Reviewed Publication

THE ALLIANCE FOR POTATO RESEARCH AND EDUCATION (APRE)

NEWS RELEASE 16-AUG-2021

For decades, people have often associated higher intakes of carbohydrate-containing foods with less healthy lifestyles. Yet, evidence suggests this perspective view is overly simplistic, and it is instead the type and quality of carbohydrate foods (CF) that matter most for supporting health. While some measures of carbohydrate quality exist, such methods often use highly variable – and thus unreliable – indicators. In a newly published perspective in Nutrients, a group of nutrition researchers, who collectively make up the Quality Carbohydrate Coalition-Scientific Advisory Council (QCC-SAC), outline the opportunity for a stronger, more evidence-based approach to defining quality CF to support overall health and provide clearer dietary guidance.

“To better guide food choices and nutrition literacy, the dialogue around high-quality carbohydrate foods must be advanced to consider the evolving science,” explains Adam Drewnowski, PhD, University of Washington, a QCC-SAC member. “As a first step, we conducted a scoping review of the scientific literature to examine the evidence behind existing measures of carbohydrate food quality and ways in which to build upon this work.”

The QCC-SAC is a team of six world-renowned experts in carbohydrate research, nutrient profiling, cultural competency and epidemiology. The group was assembled by the Quality Carbohydrate Coalition, which was spearheaded and is funded by Potatoes USA. The Coalition’s ambition is to assess and advance evidence to explore the role of CF in health. Collectively, the QCC-SAC members agree that, based on the evidence, carbohydrate guidance must move away from individual and unique biological interactions with foods, and towards recommendations based on intrinsic qualities of a food (i.e., nutrient- and food-based indicators). This includes shifting away from the decades-old focus on glycemic index (GI) when discussing high- versus low-quality CF.

QCC-SAC consensus: GI is a flawed (and misused) approach to defining CF quality

“GI is frequently used as a metric for carbohydrate food quality – but it is an outdated and flawed indicator with too much variability,” says Julie Miller Jones, PhD, LN, CNS, St. Catherine University (Emeritus), a member of the QCC-SAC. “In fact, GI was created as a research tool for use in the laboratory and was never intended to be used by the general population. Instead, we require a measure that reflects both a carbohydrate food’s contributions to fiber, nutrient and phytochemical intake, as well as its role in a healthy diet. An omnibus measure of carbohydrate food quality indicators that is accurate and applicable to real-life eating patterns is needed.”

Specifically, research demonstrates that GI varies considerably based on different contexts, such as eating situations (e.g., mixed meals), and based on individual characteristics (e.g., biological and behavioral factors like age, weight, physical activity and gut microbiome).

“A new review analyzing GI values found the variability with rice can fluctuate so significantly that it can be considered both a low GI and high GI food,” shares QCC-SAC member Siddhartha Angadi, PhD, University of Virginia. “Further, even the GI of bread can vary up to five-fold between individuals. These large inter-individual variations make the utilization of GI as a marker of carbohydrate food quality problematic.”

Despite its historic use to guide CF choices among consumers with type 2 diabetes, GI is not a consistent predicator of health. A 2019 series of systematic reviews and meta-analyses rated the evidence regarding the long-term effects of GI on health outcomes, such as cardiovascular disease, type 2 diabetes and colorectal and breast cancer, as “low or very low.”

“These findings support the need for a new, holistic approach to replace the overreliance on GI as a single evaluator of carbohydrate quality,” states Yanni Papanikolaou, MPH, Nutritional Strategies, Inc., a QCC-SAC member.

A new, inclusive approach to defining high-quality CF

The QCC-SAC will develop a series of papers for peer-reviewed publication that will introduce a new, validated approach for measuring CF quality, and will demonstrate how the approach can be integrated into dietary guidance tools to help people of all ages, ethnicities and cultural preferences improve their food choices. The approach will involve developing a composite measure that harmonizes multiple intrinsic CF quality indicators from the scientific literature into an easy-to-use tool.

“Compared to existing metrics, this tool will be unique, evidence-based and practical,” notes QCC-SAC member Judith Rodriguez, PhD, RD, University of North Florida. “It will reflect how people actually eat (e.g., mixed meals) and will recognize cultural patterns and traditions – a novel approach that is often underrepresented in similar dietary guidance tools.”

The QCC-SAC plans to release more details on their harmonized composite approach to assess CF quality in the coming year.  

###

The Quality Carbohydrate Coalition is a multi-stakeholder engagement of eight organizations across the food industry. Guided by the work of its Scientific Advisory Council, this group aims to support a collaborative, scientific dialogue around the unique and diverse roles that carbohydrate foods play in healthful eating.

The Quality Carbohydrate Coalition-Scientific Advisory Council (QCC-SAC) is a group of six world-renowned experts in carbohydrate research, nutrient profiling, cultural competency and epidemiology. The aim of the QCC-SAC is to determine evidence-based approaches for defining and selecting quality carbohydrate foods. Members of the QCC-SAC include Adam Drewnowski, PhD; Julie Miller Jones, PhD, LN, CNS; Judith Rodriguez, PhD, RD; Joanne Slavin, PhD, RD; Siddhartha Angadi, PhD; and Yanni Papanikolaou, MPH.

The report, “Toward an evidence-based definition and classification of carbohydrate quality foods: An expert panel report,” is published in Nutrients (doi: 10.3390/nu13082667). All QCC-SAC members were authors, supported by Kevin Comerford, PhD. Funding was provided by Potatoes USA.


JOURNAL

Nutrients

DOI

10.3390/nu13082667 

ARTICLE TITLE

Toward an Evidence-Based Definition and Classification of Carbohydrate Food Quality: An Expert Panel Report

ARTICLE PUBLICATION DATE

31-Jul-2021

Read the Full Study Summary

Adolescent Diets that Include Potatoes are Associated with Better Diet Quality

Research suggests that, among nine- to 18-year-olds, eating potatoes can be an effective strategy to modestly improve intake of key shortfall nutrients

Peer-Reviewed Publication

THE ALLIANCE FOR POTATO RESEARCH AND EDUCATION (APRE)

NEWS RELEASE 2-AUG-2021

American youth between two and 19 years-old have the lowest measures of diet quality compared to other age groups;[1] and nutrition thought leaders have called for effective strategies to reverse this trend and improve adherence to dietary recommendations. Now, new research published in Nutrients finds U.S. adolescents who eat potatoes have higher quality diets than those who do not consume potatoes, regardless of how the potatoes are processed or prepared. Compared to no potato consumption, results showed that eating potatoes in any form (baked, boiled, mashed, in mixed dishes and fried) was associated with higher intakes of several essential nutrients, including dietary fiber and potassium – two nutrients of public health concern[2] – and improved nutrient adequacy.

“The potato is a nutrient-dense vegetable that provides important, critically under-consumed nutrients to adolescent diets,” says Victor Fulgoni, III, PhD and study co-author. “Given their popularity—more than half (56%) of those surveyed reported eating some form of potatoes—there are opportunities to lean into these findings to make it easier for young people to find, cook and enjoy potatoes as part of a healthy dietary pattern.”

Researchers gathered dietary information from 16,633 nine- to 18-year-olds participating in the National Health and Nutrition Examination Survey (NHANES) 2001-20018. This study used Healthy Eating Index-2015 (HEI), a validated measure of diet quality, to determine how closely the participants’ diets adhered to the 2015-2020 Dietary Guidelines for Americans. Although differences in HEI scores between potato consumers and non-consumers were statistically significant, the changes were modest; for many nutrients, intake and adequacy improved with increasing potato consumption. Specifically:

  • HEI scores were 4.7% higher among those who consumed potatoes that were baked/boiled, mashed or eaten as part of a mixed dish compared to those who ate no potatoes.
  • HEI scores were 2% and 1.6% higher than potato non-consumers, respectively, among adolescents who ate either fried potatoes or those who ate fried potatoes and/or potato chips.

“Our findings show that potatoes play an important role with helping adolescents better meet the recommendations set forth in the Dietary Guidelines for Americans,” notes Fulgoni. “This is an important goal as, according to the USDA Agricultural Research Service, children and adolescents have the lowest HEI scores among any age group in the U.S. – just 53 out of an ideal HEI score of 100.”

“Our results also bring attention to the ‘company potatoes keep,’” Fulgoni adds. “Fried potatoes and potato chips are often paired with less nutrient-dense foods, which can’t be teased out in this type of study but may explain the slightly lower diet quality scores among these groups of potato eaters compared to baked/boiled potato eaters. Additional clinical trials are needed to better elucidate this situation.”

Study Design, Strengths and Limitations

Nutrition intake was determined by using two 24-hour dietary recalls. The first was conducted in person; the second was performed over the phone. Adolescents aged nine to 11 were assisted by parents or guardians, while those aged 12-18 provided recalls on their own. Based on their responses, participants were classified into one of four groups:

  • Potato non-consumers
  • Consumers of baked, boiled, mashed potatoes and potato mixtures
  • Consumers of baked, boiled, mashed potatoes and potato mixtures + fried potatoes
  • Consumers of baked, boiled, of baked, boiled, mashed potatoes and potato mixtures + fried potatoes + potato chips

Usual intake of nutrients was determined using the National Cancer Institute method, and diet quality was calculated using HEI-2015 scores after adjusting for demographic factors. The HEI-2015 includes 13 subcomponents, each reflecting an aspect of the 2015-2020 Dietary Guidelines for Americans.

The strengths of the study include its use of a large nationally representative database (NHANES 2001-2018) and the use of multiple covariates to help eliminate potential confounding factors. However, the researchers also acknowledge a few limitations namely, the cross-sectional study design cannot be used to determine causal relationships, and dietary recalls may be subject to inaccurate reporting. Additionally, even with the use of covariates, residual confounding may exist.

The research manuscript, “Intake of potatoes is associated with higher diet quality, and improved nutrient intake and adequacy among US adolescents: NHANES 2001-2018 analysis,” is published in Nutrients (https://doi.org/10.3390/nu13082614). Authors include Sanjiv Agarwal, PhD, NutriScience, LLC and Victor L. Fulgoni, III, PhD, Nutrition Impact, LLC. Funding was provided by the Alliance for Potato Research and Education, however APRE had no input on interpretation of the results or in drafting the manuscript.


[1] National Center for Health Statistics, What We Eat in America/National Health and Nutrition Examination Survey, 2015-2016. Healthy Eating Index-2015 Scores—U.S. Department of Agriculture, Center for Nutrition Policy and Promotion, access https://www.fns.usda.gov/resource/healthy-eating-index-hei

[2] U.S. Department of Agriculture and U.S. Department of Health and Human Services. Dietary Guidelines for Americans, 2020-2025. 9th Edition. December 2020. Available online: https://DietaryGuidelines.gov


JOURNAL

Nutrients

DOI

10.3390/nu13082614 

METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Intake of Potatoes Is Associated with Higher Diet Quality, and Improved Nutrient Intake and Adequacy among US Adolescents: NHANES 2001–2018 Analysis

ARTICLE PUBLICATION DATE

29-Jul-2021

Read the Full Study Summary