Experts challenge the myth of lactose-free diets
A lactose-free diet excludes milk and dairy products, including for people who have neither lactose intolerance nor an allergy to milk protein. Its supporters argue that milk protein promotes weight gain and that dairy products cause inflammation associated with excess weight.
Specialists interviewed for the report reject a direct association between milk consumption and overweight or obesity. Roberto Navarro, a medical nutrition specialist, said that people may lose weight after removing dairy because they could consume fewer calories if the foods are not replaced. He said the reduction in calorie intake, rather than the absence of dairy itself, would account for the change.
Lower-fat and semi-skimmed milk may also fit into a weight-loss diet. Nutritionist Mariana del Bosco said research indicates that calcium, which is abundant in milk and dairy products, may limit the accumulation of fat and encourage its breakdown. Navarro also cited research finding that milk protein and saturated fat can increase satiety. In that research, dieters who continued consuming milk remained full for longer than those who excluded it.
Another claim concerns abdominal bloating. People with lactose intolerance can experience bloating when lactose is fermented in the digestive system, and removing dairy can relieve that symptom. People without the condition, however, can consume milk without the same risk. Del Bosco said milk contains saturated fat, and that excessive consumption of these fats and calories can contribute to inflammation. She said that, when consumed in the recommended amount of three servings of dairy a day, milk and dairy products do not increase inflammation in healthy people.
Dairy products are described in the report as important sources of calcium for bones and teeth. Del Bosco said calcium from milk is absorbed more easily by the body than calcium from some plant foods, such as broccoli. Inadequate calcium intake raises the risk of osteoporosis, a condition in which bones become thinner and weaker because the body does not create enough new bone or absorbs too much existing bone. Weakened bones are more vulnerable to fractures.
Milk and dairy products are also identified as major sources of lactobacilli, which support the intestinal microbiota. Proper microbiota function is associated in the report with lower risks of constipation and gas-related abdominal bloating, as well as improved absorption of vitamins and minerals. The report particularly warns about removing dairy from the diet of healthy adolescents. Bone density later in life depends partly on calcium intake through the age of 20, Navarro said. If milk is excluded without being replaced by other calcium sources, the risk of osteoporosis increases.
