Effects of Pulse Consumption, Gut Microbiome, and Appetite in Healthy Participants

Human Pulse Consumption, the Microbiome, and Meal Satiety

The purpose of the study is to investigate the effects of pulse consumption versus no pulse consumption on the gut microbiome, meal satiety, and short-chain fatty acid metabolomics.

1. Investigate the acute and chronic effects of pulse consumption on the microbiome and plasma SCFA metabolomics in overweight subjects fed a high pulse (n=22) diet versus a no pulse containing diet (n=22).
2. Furthermore, we will quantitate the rate of production of plasma SCFA, markers of satiety (PYY, GLP-1 and ghrelin), blood lipids, and carbohydrate (CHO) metabolism (glucose levels and oxidation) during a standardized meal to determine the effects of consuming pulses on appetite and satiety after acute and chronic dietary consumption.
3. We will conduct subjective appetite assessments to investigate appetite control over the short- and long-term.

Inclusion Criteria:

• Men and women (premenopausal only)

• Age 20-55y (we will attempt to start baseline testing at the same time of the menstrual cycle (luteal) for the women

• BMI ≥25 or ≤40 kg/m2 (most at risk for metabolic abnormalities and will benefit from a pulse intervention-2/3 of Americans are overweight or obese)

• Weight stable (no fluctuations in body weight of greater than 4 kg in the last 3 months)

• Willing to consume a research diet

• Willing to provide blood and fecal samples

• Sedentary to low active physical activity status (less than 7200 steps per day)

• Stably treated with statin drugs, anti-hypertensives, and anti-depressants. These are acceptable as long as the drug category does not alter appetite, body weight, or the microbiome (if known)

• Pre-diabetes acceptable (glucose <125 mg/dL or HbA1c < 6.5%)

• At least one characteristic of the metabolic syndrome (but not diabetic)

  1. A large waistline: 35 inches or more for women 40 inches or more for men
  2. High triglycerides: 150 mg/dL or higher
  3. Low HDLc level: <50 mg/dL for women <40 mg/dL for men
  4. High blood pressure ≥130/85 mmHg
  5. Fasting blood sugar ≥100 mg/dL - Pre-diabetes acceptable (glucose <125 mg/dL or HbA1c <6.5%) -

Exclusion Criteria:

• Pregnant or lactating
• Postmenopausal (evidence suggests an interplay between the gut microbiome)
• BMI of <25 or >40 kg/m2
• Use of medications that affect the gut microbiome (e.g. antibiotics)
• Taking medications known to affect appetite (e.g., phentermine) or gastrointestinal function (e.g., metformin)
• On a special diet or undergoing weight loss, vegetarian, or other restricted dietary patterns
• Ad libitum intake of fiber above 25g/day (mean intake in the US population is 17g/day) and < 10g/d
• History of disease (example colon cancer, HIV, cardiovascular disease, psychiatric disorders, etc.)
• Use of tobacco products