Potatoes, Type 2 Diabetes, and Cardiometabolic Health

Official title

Cardiometabolic Effects of a Potato-rich Diet in Older Adults at Increased Risk of Developing Type 2 Diabetes: A Randomized Controlled Feeding Study

Overview

Type 2 diabetes (T2D) is a major chronic health condition which increases risk of coronary artery disease, frailty, cognitive decline, and mortality. Additionally, hypertension is a major comorbidity for individuals with T2D, further increasing the risk of adverse cardiovascular outcomes. The prevalence of both conditions increases with advancing age. There is an urgent need to identify new approaches to prevent the development of T2D and improve cardiometabolic health in older adults 50-70 years of age. Whole white potatoes are an unprocessed food rich in essential nutrients often under-consumed by Americans, including potassium, fiber, magnesium, vitamins C and B6, and phytochemicals. Each of these nutrients individually are associated with cardiometabolic health benefits. Potatoes account for a significant amount of the intake of these nutrients in the US diet and are well-positioned to be a foundational element of a healthy dietary pattern. However, there are few interventional studies evaluating the effect of potatoes on cardiometabolic health, and the evidence from observational studies is mixed, leaving a significant gap in knowledge regarding the potential for potatoes to be included in healthy dietary patterns. The results of our proposed study will provide foundational data that inform future dietary guidelines regarding the inclusion of white potatoes as part of a healthy US dietary pattern.

Interventions

• Other Controlled diet: Potato-rich healthy dietary pattern
  Following a 2-week eucaloric lead-in diet, participants will be provided and consume a potato-rich healthy dietary pattern for 12 weeks. The intervention diet will be eucaloric and matched for macronutrient composition with the control diet. Whole white potatoes will be incorporated into the intervention diet in different forms. This diet will have an healthy eating index (HEI) score of 85.
• Other Controlled diet: Typical Western-style dietary pattern
  Following a 2-week eucaloric lead-in diet, participants will be provided and consume a typical Western-style dietary pattern for 12 weeks. The control diet will be potato-free, eucaloric, and matched for macronutrient composition with the intervention diet. This diet will have an healthy eating index (HEI) score of 58.

Primary outcome measures

• Change in glucose tolerance from baseline to 12 weeks post potato-rich healthy diet vs typical Western-style diet [Time frame: 2-hour test in laboratory, 2 timepoints (baseline, 12-weeks post intervention diets)]
• Change in insulin sensitivity from baseline to 12 weeks post potato-rich healthy diet vs typical Western-style diet [Time frame: 2-hour test in laboratory, 2 timepoints (baseline, 12-weeks post intervention diets)]
• Change in glucose control (AUC) from baseline to 12 weeks post potato-rich healthy diet vs typical Western-style diet [Time frame: 7-day measurement during free-living, 2 timepoints (baseline, 12 weeks post intervention diets)]
• Change in blood pressure from baseline to 12 weeks post potato-rich healthy diet vs typical Western-style diet [Time frame: 20-minute measurement in the laboratory, 2 timepoints (baseline, post 12 week intervention diets)]

Secondary outcome measures (3)

• Change in inflammatory biomarker tumor necrosis factor alpha from baseline to 12 weeks post potato-rich healthy diet vs typical Western-style diet [Time frame: 5-minute blood collection in laboratory, 2 timepoints (baseline, post 12 week intervention diets)]
• Change in inflammatory biomarker interleukin-6 from baseline to 12 weeks post potato-rich healthy diet vs typical Western-style diet [Time frame: 5-minute blood collection in laboratory, 2 timepoints (baseline, post 12 week intervention diets)]
• Change in inflammatory biomarker monocyte chemoattractant protein-1 from baseline to 12 weeks post potato-rich healthy diet vs typical Western-style diet [Time frame: 5-minute blood collection in laboratory, 2 timepoints (baseline, post 12 week intervention diets)]

Eligibility criteria

Inclusion criteria

• Age 50-70 years
• Weight stable for previous 3 months (±5% body weight)
• Sedentary to recreationally active
• ADA-Risk Screener questionnaire score of at least 5
• No plans to gain or lose weight or change physical activity level
• Willing to pick up food daily and consume foods provided for a 14-week period
• Verbal and written informed consent
• Estrogen or testosterone use, lipid-lowering or blood pressure medication and thyroid replacement medication is acceptable, if on stable dose for >6 months

Exclusion criteria

• Body mass index >40 m2/kg
• Diabetes or diabetes medication
• Weight loss medication or medication influencing glucose metabolism
• Antibiotic, prebiotic or probiotic use in prior 3 months
• TCHOL >6.2 mmol/L; TG >4.5 mmol/L
• Blood pressure (BP) > 159/99 mmHg
• Diagnosed inflammatory bowel disease
• Past or current heart diseases, stroke, respiratory disease, endocrine or metabolic disease, or hematological-oncological disease
• Vegetarian or vegan
• Pregnant or plans to become pregnant
• Food allergies or aversions to diet foods provided
• Estrogen or testosterone usage, lipid-lowering medication, blood pressure medication usage <6 months

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: Yes

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Single blind

Primary purpose

Prevention

Study locations

United States · 1 center

• Virginia Polytechnic Institute and State University — Blacksburg

Identifiers

NCT: NCT07229482 · 25-897

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗