clinical trial to assess the effects of dairy on insulin sensitivity and β-cell function

Conditions: Diabetes

Summary: the aim of this trial is to evaluate the effects of dairy product consumption on insulin sensitivity and pancreatic β-cell function in men and women at risk for the development of type 2 diabetes mellitus (t2dm) who habitually consume beverages high in sugar (non-diet sodas and fruit juice cocktails).


Eligibility criteria:
inclusion criteria: * subject is male or female, 18-74 yrs of age, inclusive * subject reports habitual consumption of ≥2 servings/d of high-sugar beverages (e.g., non-diet soda, fruit juice cocktails) * subject has waist circumference ≥33.0 inches for women and ≥36.0 inches for men * subject is at risk for development of type 2 diabetes mellitus (t2dm), based on 1 or more of the following: fasting glucose 100-125 mg/dl; glycosylated hemoglobin 5.7-6.4%, or ≥20% risk of developing diabetes in the next 7.5 yrs based on the san antonio heart study prediction equation * subject has a score of 7-10 on the vein access scale at screening * subject is normally active and judged to be in good health on the basis of medical history, physical examination and routine lab tests * if female, subject is willing to schedule treatment visits during the follicular phase of the menstrual cycle, defined as days 1-14, where day 1 is 1st day of menses * subject has a menstrual cycle duration ranging in length form 24-36 d (if premenopausal) * subject is willing to maintain a stable body weight and follow his/her habitual diet and exercise pattern, except for inclusion of study product, throughout the trial * subject is willing to maintain his or her habitual intake of coffee, tea, and alcoholic beverages throughout the trial * subject agrees to limit intake of non-study related dairy products to ≤1 serving per day during each treatment period * subject is ambulatory and willing to refrain from vigorous physical activity and consumption of alcoholic beverages 24 h prior to each test day * subject has no plans to change smoking habits during the study period * subject is willing to abstain from tobacco use 1 h prior to and during visits on lmtt test days * subject has no health conditions that would prevent him/her from fulfilling the study requirements as judged by the investigator on the basis of medical history and routine lab test results exclusion criteria: * subject has abnormal lab test results of clinical importance, including, but not limited to, tg ≥400 mg/dl, fasting creatinine ≥1.5 mg/dl, alanine aminotransferase or aspartate aminotransferase ≥1.5 times the upper limit of normal at screening * subject has a body mass index ≥45.0 kg/m2 * subject has fasting blood glucose ≥126 mg/dl at screening or known diabetes mellitus (type 1 or t2dm) * subject has a habitual intake of ≥4 servings/d of dairy food and beverages * subject has known allergy or sensitivity to study product or any ingredients of study product. subjects with lactose intolerance will be allowed to use products such as lactaid dietary supplements * subject has a history of coronary heart disease, congestive heart failure, or serious ventricular dysrhythmias (ventricular tachycardia or fibrillation) * subject has a change in body weight of \>4.5 kg within 4 weeks of screening * subject uses medications known to influence carbohydrate metabolism * subject has recent use of antibiotics * subject has an active infection * subject has unstable use of anti-hypertensive medications, thyroid hormone replacement, or lipid-altering drugs within 4 weeks of screening * subject has unstable use of lipid-altering foods or dietary supplements within 4 weeks of screening * subject uses niacin at doses \>200 mg/d within 4 weeks of screening * subject has history of extreme dietary habits, e.g., atkins, high protein * subject has a history or presence of clinically important endocrine, cardiac, renal, hepatic, pulmonary, biliary, pancreatic, gastrointestinal, or neurologic disorders that could interfere with interpretation of study results * subject has history of dysphagia, swallowing disorders, or intestinal motility disorders * subject has history of cancer * subject has uncontrolled hypertension at screening (systolic blood pressure ≥160 mm hg or diastolic blood pressure ≥100 mm hg)

Keywords: insulin sensitivity