Excessive intake of rapidly digestible starches increases metabolic risks. This randomized crossover trial involved twenty-two healthy adults (age 29 ± 6 years, BMI 21.6 ± 1.8 kg/m2). Participants completed 5–10 sessions with 7-day washouts. The study examined whether preloading leafy vegetables (200 g) ± canola oil (20 g) modulates starch digestion (300 g mashed potatoes) by stimulating GLP-1 and delaying gastric emptying. Based on a ≥ 10-minute preloading interval identified in an exploratory Phase Ι pilot (n = 10), the powered Phase II trial (n = 22) demonstrated significant treatment×time interactions for the effect of preloading on postprandial glycemic and insulin responses (p < 0.001) using linear mixed-effects models. Oil-containing preloads resulted in blunted postprandial blood glucose and insulin responses, delayed gastric emptying (p < 0.001), and higher GLP-1 (p < 0.001). Satiety and ad libitum energy intake remained unchanged. Furthermore, despite identical nutrients, co-ingestion underperformed timed preloading. In conclusion, an oil-containing vegetable preload modulates glycemic kinetics, offering a practical “food-first” strategy for post-meal glycemia management.
Research Category: Cardiometabolic Health
Associations of white potato intake and preparation methods with cardiometabolic health measures in US adults categorised by diabetes status
White potatoes are a major contributor to energy and nutrient intake in the USA, which supports investigating their relationship with cardiometabolic health. This cross-sectional analysis assessed relationships of total white potato intake and dietary patterns containing white potatoes prepared by various methods with markers of cardiometabolic health in adults categorised by diabetes status. The dietary intake assessment component of the National Health and Nutrition Examination Survey (2001-2018), What We Eat in America (WWEIA), was linked with the Food and Nutrient Database for Dietary Studies and Food Patterns Equivalents Database to rank the consumption of white potato-containing foods. Dietary patterns were determined by percent calories from white potatoes and main food groups in WWEIA using cluster analysis. Regression analysis assessed trends in individuals with (n 5,467) and without (n 38,159) diagnosed diabetes. P < 0·01 was significant. The most consumed white potato-containing foods were French fries, potato chips and home fries. In adults without diagnosed diabetes, total white potato intake was positively associated with glucose, insulin, Homeostatic Model Assessment for Insulin Resistance and waist circumference. Glycated Hb was lower in those who primarily consumed dietary patterns with baked/boiled potatoes, and waist circumference was higher in those who primarily consumed dietary patterns with chips, fried potatoes or mashed potatoes compared with adults with no white potato intake. In adults without diagnosed diabetes, total white potato intake was associated with greater cardiometabolic risk, which may be due, in part, to frying as the predominate preparation method of white potatoes in the USA.
Potato Consumption and Risk of Cardiovascular Disease in a Harmonized Analysis of Seven Prospective Cohorts
Background/Objectives: While previous study results have suggested an elevated risk of type 2 diabetes with potato consumption, limited and inconsistent results are available on the association of potato consumption with the risk of cardiovascular disease (CVD) and hypertension (HTN). We assessed the associations of (i) total potato consumption with the risk of CVD and HTN as the primary aim and (ii) fried potatoes and combined baked, boiled, and mashed potatoes with the risk of CVD and HTN as the secondary aim.
Methods: We conducted a meta-analysis using data from seven cohorts for CVD (n = 110,063) and five cohorts for HTN (n = 67,146). Cox regression was used to estimate multivariable adjusted hazard ratios separately in each cohort and the cohort-specific results were meta-analyzed using an inverse-variance weighted method.
Results: The mean age ranged from 25 to 72 years, 65% of the respondents were women, and the mean consumption of total potatoes ranged from 1.9 to 4.3 times per week. In the primary analysis, total potato intake was not associated with the risk of either CVD or HTN: multivariable adjusted HR (95% CI) comparing 5+ servings/week to no potato intake: 0.96 (0.89–1.04) for CVD and 1.04 (0.99–1.08) for HTN. In secondary analyses, the consumption of combined baked, boiled, and mashed potatoes was not associated with CVD or HTN; while fried potato consumption was not associated with CVD risk, there was a 10% higher risk of HTN (95% CI: 4% to 17%) comparing 1+ servings/week to no fried potato intake.
Conclusions: While the consumption of total potato was not associated with the risk of CVD or HTN risk, a modest elevated risk of HTN but not CVD was observed only with fried potato consumption.
Dietary Approaches to Stop Hypertension (DASH) Diet and Blood Pressure Reduction in Adults with and without Hypertension: A Systematic Review and Meta-Analysis of Randomized Controlled Trials
A clinical trial examining the effects of following a DASH eating plan that either includes five servings of fried potatoes, five servings of non-fried potatoes, or no potatoes each week, for five weeks, on blood pressure, other anthropometric measures and subjective feelings of hunger and satiety among adults with type 2 diabetes. All study participants will consume the same standard DASH eating plan for a three-week period, followed by a random assignment to one of the test DASH eating plans.
Carbohydrate confusion and dietary patterns: unintended public health consequences of “food swapping”
The 2025–2030 United States Dietary Guidelines process is currently underway, and the 2025 Dietary Guidelines Advisory Committee is examining and evaluating a list of prioritized scientific questions identified by the United States Department of Health and Human Services and the United States Department of Agriculture. One of the questions that will be evaluated is if changes should be made to USDA Dietary Patterns based on whether starchy vegetables and grains are, or can be, consumed interchangeably. These foods have historically been classified in distinct food groups. Menu modeling analyses evaluating the impact of replacing starchy vegetables with grains result in declines in key nutrients of concern. Given their unique nutrient contributions and the fact that many cultural foodways within the United States population include both starchy vegetables and grains, it is important for dietary recommendations to continue to categorize starchy vegetables and grains separately.
Perspective: Potatoes, Quality Carbohydrates, and Dietary Patterns
Potatoes have long been a staple food in many cultures and cuisines, but they have gained a reputation as a low-quality carbohydrate source that should be avoided in the diet. Historically, this view has been justified by citing the glycemic index of potatoes as the main indicator of their quality. However, their nutrient composition should also be considered. The association of potatoes with energy-dense Western dietary patterns has also contributed to a perception that potatoes are inherently unhealthy. Although some studies have suggested an association between potato consumption and increased risk of health problems, such as type 2 diabetes, these associations may be confounded by fried potato intake and are strongest at intake levels higher than average consumption rates. Epidemiologic data suggest total potato intake is not a health risk in Eastern populations and can be consumed as part of a healthy diet. Furthermore, clinical trial data demonstrate that potatoes’ health impact, irrespective of preparation, is similar to legumes and comparable with refined grains, with few deleterious effects found. These findings highlight the importance of moving beyond the glycemic index and adopting a more nuanced evaluation of the epidemiologic data to better understand the health impact of potato intake. Ultimately, the negative reputation of potatoes stems from an overinterpretation of their glycemic index and association with unhealthy Western dietary patterns, as well as oversimplification of the epidemiologic data. By considering carbohydrate quality, it becomes clear that potatoes can be part of a healthy diet given the proper consideration.
Effect of potatoes as part of the DASH diet on blood pressure in individuals with and without type 2 diabetes: A randomized controlled trial
This randomized controlled trial evaluated different cooking methods of potatoes as part of the DASH diet on blood pressure (BP) and anthropometrics in people with and without type 2 diabetes (T2D). Participants were randomized into DASH-FP (fried potatoes), DASH-NFP (non-fried potatoes) or DASH-NP (no potatoes) groups. BP, weight, waist circumference and body composition were measured.
Change outcomes from baseline to 6 weeks showed no significant difference in the study outcomes, including diastolic BP (p = 0.12), systolic BP (p = 0.26), body weight (p = 0.11), waist circumference (p = 0.86) and body composition (p = 0.57) within study groups. A significant group T2D status interaction was found for waist circumference (p = 0.036). Results from pairwise comparisons between the groups for all outcomes were not significant; however, a positive trend was seen in DASH-NFP and DASH-FP diet groups in BP and anthropometrics.
Individuals with and without T2D that consumed potatoes and the DASH diet did not significantly change BP and anthropometrics by six weeks. Slight improvements in BP and anthropometrics were seen in non-fried and fried potato groups. This helps future investigations of popular foods for people with chronic conditions that can be incorporated in a healthy eating pattern.
Low-Energy Dense Potato- and Bean-Based Diets Reduce Body Weight and Insulin Resistance: A Randomized, Feeding, Equivalence Trial
We evaluated the effect of diets low in energy density (1 kcal/g) and high in either potatoes (Potato) or pulses (Bean) on blood glucose control in participants with insulin resistance. We hypothesized that the Potato and Bean diets would have equivalent effects. This was an 8-week randomized, parallel design, controlled feeding study comparing Potato and Bean diets (50–55% carbohydrate, 30–35% fat, 15–20% protein). Equivalence was prespecified as the mean change in the blood glucose concentration for Potato that was within ±20% of the Bean diet. Thirty-six participants (age: 18–60 years, body mass index: 25–40 kg/m2) with insulin resistance (homeostatic model assessment of insulin resistance [HOMA-IR] >2) were enrolled. Body weight was measured, and subjects underwent a mixed meal tolerance test at baseline and after 8 weeks. Intent-to-treat (ITT) and completer analyses were conducted. Equivalence between the two diets in the area under the curve for serum glucose was attained within ±10%, but the reduction from baseline was not statistically significant. For the Bean diet, insulin (area under the response curve: −2136.3 ± 955.5 mg/[dL∙min], = .03) and HOMA-IR (−1.4 ± 0.6, = .02) were lower compared with baseline. ITT and completer analyses were similar, except that HOMA-IR was also reduced by the Potato diet (−1.3 ± 0.6, < .05). Compliance with the diets was 87–88%, and body weight was reduced in both diets (Potato: −5.6% ± 0.6%; Bean: −4.1% ± 0.6%, < .001) with no significant difference between the two diets. Potato and Bean diets low in energy density were equally effective in reducing insulin resistance and promoting weight loss in individuals with impaired blood glucose control.
Potato consumption is not associated with cardiometabolic health outcomes in Framingham Offspring Study adults
Some consider potatoes to be unhealthy vegetables that may contribute to adverse cardiometabolic health outcomes. We evaluated the association between potato consumption (including fried and non-fried types) and three key cardiometabolic outcomes among middle-aged and older adults in the Framingham Offspring Study. We included 2523 subjects ≥30 years of age with available dietary data from 3-d food records. Cox-proportional hazards models were used to estimate hazard ratios (HRs) and 95 % confidence intervals (CIs) for hypertension, type 2 diabetes or impaired fasting glucose (T2DM/IFG), and elevated triglycerides, adjusting for anthropometric, demographic and lifestyle factors. In the present study, 36 % of potatoes consumed were baked, 28 % fried, 14 % mashed, 9 % boiled and the rest cooked in other ways. Overall, higher total potato intake (≥4 v. <1 cup-equivalents/week) was not associated with risks of T2DM/IFG (HR 0⋅97, 95 % CI 0⋅81, 1⋅15), hypertension (HR 0⋅95; 95 % CI 0⋅80, 1⋅12) or elevated triglycerides (HR 0⋅99, 95 % CI 0⋅86, 1⋅13). Stratified analyses were used to evaluate effect modification by physical activity levels and red meat consumption, and in those analyses, there were no adverse effects of potato intake. However, when combined with higher levels of physical activity, greater consumption of fried potatoes was associated with a 24 % lower risk (95 % CI 0⋅60, 0⋅96) of T2DM/IFG, and in combination with lower red meat consumption, higher fried potato intake was associated with a 26 % lower risk (95 % CI 0⋅56, 0⋅99) of elevated triglycerides. In this prospective cohort, there was no adverse association between fried or non-fried potato consumption and risks of T2DM/IFG, hypertension or elevated triglycerides.
French-fried potatoes consumption and energy balance: a randomized controlled trial
Background: Epidemiologic observations suggest increased potato consumption correlates with weight gain, adiposity, and diabetes risk, whereas nut consumption is associated with weight control and metabolic health. Randomized controlled trial (RCT) data indicate humans respond to changes in energy intake in single dietary components and compensate for extra energy consumed.
Objectives: We completed an RCT testing whether increased daily potato consumption influences energy balance [specifically, fat mass (FM)] compared with calorie-matched almond consumption.
Methods: A 30-d RCT of 180 adults prescribed calorie-matched (300 kcal/d, n = 60 participants/group) than consumed 1 of the following: 1) almonds (almond group), 2) French fries (potato group), or 3) French fries with herb/spices mix (potato + herb/spices group). Baseline and 30-d FM were measured by DXA (primary outcome), with secondary outcomes including body weight and carbohydrate metabolism markers [glycated hemoglobin (HbA1c), fasting blood glucose and insulin, HOMA-IR)]. A subset of 5 participants/group participated in a postprandial meal-based tolerance test.
Results: A total of 180 participants were randomly assigned [gender: 67.8% female; mean ± SD age: 30.4 ± 8.7 y; BMI (in kg/m2): 26.1 ± 4.2; and weight: 75.6 ± 15.4 kg], with 12 dropouts and 3 terminations. No significantly different FM changes were observed between almond and potato consumption [combined ± herb/spices; mean ± SE almond: 230.87 ± 114.01 g; potato: 123.73 ± 86.09 g; P = 0.443], fasting glucose (P = 0.985), insulin (P = 0.082), HOMA-IR (P = 0.080), or HbA1c (P = 0.269). Body weight change was not significantly different in the potato groups combined compared with the almond group (P = 0.116), but was significantly different among the 3 groups (P = 0.014; almond: 0.49 ± 0.20 kg; potato: -0.24 ± 0.20 kg; potato + herb/spices: 0.47 ± 0.21 kg). In meal tests, significantly lower post-prandial glucose and insulin responses to almonds compared with potatoes were observed (P = 0.046, P = 0.006, respectively), with potato + herb/spices having intermediate effects.
Conclusion: There were no significant differences in FM or in glucoregulatory biomarkers after 30 d of potato consumption compared with almonds. Results do not support a causal relation between increased French fried potato consumption and the negative health outcomes studied. This trial was registered at clinicaltrials.gov as NCT03518515.