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.

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