Whole Milk Intake and Cardio-metabolic Risk Factors

Study Overview
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Brief Summary
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Milk is the source of high-quality protein, calcium, and other vitamins and minerals. Epidemiologic studies have linked high consumption of milk with risk of metabolic syndrome, T2DM, hypertension and obesity, which are independent risk factors of cardiovascular disease. However, milk contains disaccharide lactose, which may cause gastrointestinal problems in those adults with poor digestion. Recent studies have shown that subjects with intolerance to lactose tend to reduce their consumption of milk. Actually, consumption of 12g lactose (240ml milk) per day produces negligible symptoms in lactose intolerant. Furthermore, a dairy-rich diet could improve lactose intolerance because of colonic adaption to it. Lactose maldigestion would not be a restricting factor in milk intake. In general, the undigested lactose will be fermented by colonic bacteria into hydrogen, carbon dioxide, and short-chain fatty acids (SCFA: acetate, propionate, and butyrate). The SCFAs may have beneficial effects on human glucose and lipid metabolism, and the lactose fermentation may change the intestinal flora profile. But there are few studies evaluating effect of milk intake on health of people with lactose malabsorption or intolerance.This trial intend to study the effect of whole milk on cardio-metabolic risk factors of healthy person with or without lactose maldigestion.

Official Title
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Effect of Whole Milk Intake on the Cardio-metabolic Risk Factors of Healthy Person With or Without Lactose Maldigestion

Conditions
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Lactose Malabsorption, Cardiovascular Disease

Intervention / Treatment
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* Dietary Supplement: full-fat milk


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Aged above 18 years of age Able to give informed connect Exclusion Criteria: Unwilling to trial dietary intervention Pregnancy Known cardiovascular disease (stroke, ischemic heart disease and so on), diabetes, hypertension and any other chronic disease. Known gastrointestinal disease, such as Irritable Bowel Syndrome(IBS), functional bowel disease and so on. Evidence of drug or alcohol abuse

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: lactose digesters<br>Participants in arm 1 are grouped as lactose digesters based on breath hydrogen test after a 25-g lactose load. The breath hydrogen excretion is less than 20 ppm. | Dietary Supplement: full-fat milk<br>* intake 250ml full-fat milk per day, do not intake any other dairy products<br>|
| Active Comparator: lactose maldigesters<br>Participants in arm 2 are also grouped as lactose maldigesters based on breath hydrogen test after a 25-g lactose load. The breath hydrogen excretion is not less than 20 ppm. | Dietary Supplement: full-fat milk<br>* intake 250ml full-fat milk per day, do not intake any other dairy products<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in body weight |  | 4 weeks | 
| Change in body composition (body fat mass and lean mass) | Body fat mass and lean mass measured by Bioelectric Impedance Analysis(BIA) | 4 weeks | 
| Changes in blood pressure | Systolic Blood Pressure and Diastolic Blood Pressure before and after milk intervention | 4 weeks | 
| Changes in blood lipids profile | Fasting plasma Total cholesterol, Low Density Lipoprotein, High Density Lipoprotein and triglycerides before and after milk intervention | 4 weeks | 
| Changes in fasting plasma glucose |  | 4 weeks | 
| Changes in fasting plasma insulin |  | 4 weeks | 
| Changes in fasting plasma C-peptide |  | 4 weeks | 
| Changes in Homeostasis Model Assessment of Insulin Resistance(HOMA-IR) | Insulin sensitivity measure derived from fasting glucose and insulin | 4 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in pro-inflammatory markers | Fasting plasma C-reactive protein, interleukin-6 and tumor necrosis factor-α before and after milk intervention | 4 weeks | 
| Changes in markers of oxidative stress | Fasting plasma MDA, oxidized LDL before and after milk intervention | 4 weeks | 
| Biomarkers in urine |  | 4 weeks | 
| Changes in fecal fat excretion |  | 4 weeks | 
| Changes in fecal short chain fatty acids (SCFA) | Fecal acetate, propionate, butyrate before and after milk intervention | 4 weeks |