Understanding the Role of Dairy Foods in Weight Management
Obesity has risen significantly in the United States and is predicted to become the most prevalent public health problem in the United States. Thirty percent of American adults aged 20 - 74-more than 60 million people-are obese. The number of children and teens who are overweight has tripled since 1980. Sixteen percent of children 6 - 19 years-more than 9 million-are considered overweight. If weight gain continues at its present rate, 39% of Americans are estimated to be obese in 2008. Overweight and obesity is a major public health concern because excess body fat leads to a higher risk for premature death and for many chronic diseases and conditions including type 2 diabetes, cardiovascular disease, hypertension, stroke, insulin resistance syndrome, gout, osteoarthritis, and some cancers (e.g. colon, endometrial, postmenopausal breast). The total health care costs attributed to obesity-related diseases in 2000 were estimated at
$117 billion. As a result, federal government and state agencies, the food and beverage industry and health professional organizations are desperately seeking ways to reduce the nation's obesity epidemic.
Observational evidence: Support for dairy foods' beneficial role in weight management comes from several observational studies that evaluated the link between calcium/dairy intake and body weight. One such study, the Coronary Artery Risk Development in Young Adults (CARDIA), followed 3,157 adults for 10 years. Among overweight and obese adults, the obesity occurrence and weight gain risk over 10 years was 67% lower in those consuming the most dairy foods versus those consuming the least. Neither the type of dairy product nor its fat content affected the study results. The Quebec Family Study of nearly 500 adults reported that women who consumed less than 600 mg calcium per day had greater body weight and body fat than women who consumed more than 600 mg calcium per day. A similar pattern was observed for body fat in men. Most studies in children and adolescents have also shown either inverse or neutral associations between calcium/dairy foods and body weight and fat. To date, the majority of observational and clinical studies support a beneficial relationship between dairy food intake and lower body weight and body fat. The failure of some studies to support this association may be explained by factors such as high baseline calcium intakes, lack of control of energy intakes, and/or use of normal weight subjects.