Dairy foods not impacting on weight issue: study
goods may play a key role in weight loss or gain are not
sufficiently supported by scientific testing, according to a new
review of existing research.
In a review of 49 randomized clinical trials on the impact of dairy products and calcium supplements on body weight, no specific link was found on the whole, according to the findings published in the journal Nutrition Reviews. The dairy industry has moved in recent months to play up the dietary benefits of its products in helping to combat obesity, particularly in regards to a balanced diet. While the research does not lend itself to supporting these claims, it also fails to suggest that dairy goods alone may exacerbate weight gain. Overall the review, which was conducted by Dr Amy Lanou and physician Neal Barnard, found that 41 studies showed there was no specific affect from dairy on body weight, while by contrast, only five established a pattern of weight loss. Two of the clinical tests suggested that dairy actually encouraged weight gain, with another concluding that it helped slow the rate at which body fat increased. Balanced diet In addressing reasons as to why some observational studies has found a reduction in weight gain with increased dairy or calcium consumption, the study suggested that other dietary and lifestyle habits was a likely factor. The researchers highlighted a CARDIA study, which found that dairy consumption was positively associated with whole grain, fruits vegetable and saturated fat intake, though was linked more negatively to weight when studied with sugar-sweetened soft drinks. In another study in Women's Health, research suggested that females shown to have a higher intake of calcium were less likely to smoke or drink, while also more prone to exercise and use multivitamins. The study also suggested that calcium intake was also linked with dietary fiber along with fat and cholesterol, the researchers said. Dairy impact The report found generally that where links between dairy and calcium intake and weight were found, there was more evidence of a decreased rate of weight gain than an all out loss. Method The clinical trials were categorized between studies that used an energy restriction protocol and those that did not. Other important consideration factors for the review included participants age and whether testing looked solely at either dairy, calcium supplementation or both. Out of 49 trails that were reviewed, the vast majority - 38 - looked specifically on the impact of dairy products or calcium on bone health, weight and body mass index (BMI), the researchers said. Of this group of trials, a total of 18 were focused on adults and children, with the remaining 20 tests looking at the impact on adult participants. The additional eleven studies considered by the review looked at how calcium or dairy supplements influenced weight change along with energy restriction. Age differences While the researchers said that gradual levels of weight gain in children were to be expected, testing within the age group focused on whether dairy or calcium products could help prevent obesity or excess fat from occurring. For adult participants, the researchers said that studies instead tended to address potential weight loss or gain. The tests also considered factors such as the stage of life and health status of participants as an important area of concern. Industry view Obesity has become an increasingly important topic in food and beverage production as consumer concerns grow over the need for health and nutritional benefits in their products. The dairy industry claims that it can therefore aid and not hinder moves towards encouraging healthier diets. These claims were backed by Dr Cindy Schweitzer, technical director for the industry consortium Global Dairy Platform. "According to over 30 studies, milk products could play a role in losing and maintaining weight," she told delegates at an UK-based industry wide conference held earlier this year. "In fact, these studies reveal that milk products may help you lose weight as part of a low-calorie diet, or help prevent weight gain." However, Dairy UK chairman and British politician David Curry said that governments and education systems should dedicate themselves to promoting the importance of having a balanced diet. "Only then can you communicate true nutritional advice, so we struggle with strategies which seek only to reduce targeted single components in food," he stated. These sentiments were backed in part by national health charity The British Heart Foundation, which stressed that no one type of food or beverage product could ensure a health diet. A spokesperson for the charity said that a balanced diet, reliant on no one particular food stuff, therefore remained the best way for consumers to stave off obesity. Source: Nutrition Reviews Volume 66, Number 5, pages 272-279 "Dairy and weight loss hypothesis: an evaluation of the clinical trials"Authors: A. Lanou and Neal Barnard
