Diet and Health in Adults With Metabolic Syndrome

Study Overview
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Brief Summary
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The prevalence of US adults with Metabolic Syndrome (MetS) is over 34%, impacting nearly 35% of all adults and 50% of those aged 60 years or older. MetS is characterized as a combination of underlying risk factors that when, occurring together, increase the risk for chronic diseases such as type 2 diabetes mellitus (T2DM), cardiovascular disease, stroke, and certain types of cancer, resulting in an 1.6-fold increase in mortality. According the American Heart Association, health risks associated with Metabolic Syndrome can be significantly reduced by reducing body weight and eating a diet that is rich in whole grains, fruits, and vegetables. Potatoes (e.g. skin-on white potatoes) are an excellent source of potassium, vitamin C, and vitamin B6 and a good source of magnesium and dietary fiber. In addition, the potato has greater dry matter and protein per unit growing area compared with cereals. Despite this, consumers tend to believe that potatoes are high in calories and in fat compared with other carbohydrate sources such as rice or pasta, an incorrect assumption since a potato has negligible fat and a low energy density similar to legumes. Data from short-term nutrition intervention trials, suggest that potatoes consumed as part of a low-glycemic load meal can play a role in the prevention or treatment of MetS. However, the impact of long-term potato consumption on cardiometabolic risk factors associated with MetS is not known. Therefore, there is a critical need to determine if regular (> 4 times per week) potato consumption can improve cardiometabolic health in individuals with MetS.

Official Title
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The Effect of a Higher Protein, Lower Glycemic Load Diet Containing Potato or Potato-based Products on Metabolic Health in Adults With Metabolic Syndrome

Conditions
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Metabolic Syndrome

Intervention / Treatment
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* Dietary Supplement: Higher protein, low glycemic load diet


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Resides in Northwest Arkansas Age 18+ years Metabolic Syndrome (characterized by participant having three or more of the following measurements: abdominal obesity, triglyceride level over 150 mg/dl, HDL cholesterol < 40 mg/dl in men and 50 mg/dl in women, systolic blood pressure of 130 mm Hg or diastolic blood pressure of 85 mm Hg, and/or fasting glucose > 100 mg/dL) All ethnicities Female and male Currently consuming a high glycemic load diet Exclusion Criteria: Food allergies Dietary restrictions (e.g. vegetarian, vegan, etc.) Trying to lose weight in last 3 months Prescription medications related to heart disease or type 2 diabetes Fear of needles

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 85 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Higher Protein, Low Glycemic Load with Potatoes<br>Higher Protein, Low Glycemic Load with Potatoes (HPLG-P): low- to moderate- glycemic load meals containing white potatoes. Participants will consume low- to moderate-glycemic meals for 16 weeks and will need to consume at least 4 meals containing white potatoes. | Dietary Supplement: Higher protein, low glycemic load diet<br>* All dietary treatments will be designed to be isoenergetic within individual participants. Energy content of the diets will be individualized to ensure weight maintenance throughout the dietary intervention period using the Harris Benedict equation x 1.35. Glycemic load for the treatment groups will be calculated using the following equation: Glycemic Load = Glycemic Index x Grams of carbohydrates/100. Potatoes, processed potato products, and control carbohydrate foods will be provided.<br>|
| Active Comparator: Higher Protein, Low Glycemic Load with Processed Potatoes<br>Higher Protein, Low Glycemic Load with Processed Potatoes (HPLG-PP): low- to moderate- glycemic load meals containing processed white potato products. Participants will consume low- to moderate-glycemic meals for 16 weeks and will need to consume at least 4 meals containing white potatoes. | Dietary Supplement: Higher protein, low glycemic load diet<br>* All dietary treatments will be designed to be isoenergetic within individual participants. Energy content of the diets will be individualized to ensure weight maintenance throughout the dietary intervention period using the Harris Benedict equation x 1.35. Glycemic load for the treatment groups will be calculated using the following equation: Glycemic Load = Glycemic Index x Grams of carbohydrates/100. Potatoes, processed potato products, and control carbohydrate foods will be provided.<br>|
| Placebo Comparator: Higher Protein, Low Glycemic Load - Control<br>Higher Protein, Low Glycemic Load (HPLG-C): low- to moderate- glycemic load meals containing control carbohydrate (e.g. rice, pasta). Participants will consume low- to moderate-glycemic meals for 16 weeks and will need to consume at least 4 meals containing control carbohydrate sources. | Dietary Supplement: Higher protein, low glycemic load diet<br>* All dietary treatments will be designed to be isoenergetic within individual participants. Energy content of the diets will be individualized to ensure weight maintenance throughout the dietary intervention period using the Harris Benedict equation x 1.35. Glycemic load for the treatment groups will be calculated using the following equation: Glycemic Load = Glycemic Index x Grams of carbohydrates/100. Potatoes, processed potato products, and control carbohydrate foods will be provided.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Serum lipid levels | Total Cholesterol, LDL-Cholesterol, HDL-Cholesterol, Free Fatty Acids, Triglycerides | Change from baseline at 16 weeks | 
| Plasma glucose levels | Plasma glucose levels | Change from baseline at 16 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Waist circumference | Waist circumference in centimeters | Change from baseline at 16 weeks | 
| Dietary intake | Monthly food records will be recorded to determine changes in diet intake | Change of time of study (16 weeks) | 
| Mood | Mood will be measured using the Profile of Mood States questionnaire | Change from baseline at 16 weeks | 
| Sleep quality and duration | Sleep quality will be assessed using the Pittsburgh Sleep Quality Index | Change from baseline at 16 weeks | 
| Sleep duration | Sleep duration will be assessed using an Actigraph sleep monitor | Change from baseline at 16 weeks | 
| Marker of appetite and sleep | Orexin (also known as hypocretin) | Change from baseline at 16 weeks | 
| Appetite | Anorexigenic appetite hormone - PYY (peptide tyrosine tyrosine) | Change from baseline at 16 weeks |