Photo: National Dairy Council®
Overweight children in Chile who were given milk instead of soft drinks showed a significant increase in lean body mass, and the boys grew taller, a pilot study conducted by a Fogarty grantee reports.
The research led by Dr. David S. Ludwig of Children’s Hospital Boston appeared in the September issue of The American Journal of Clinical Nutrition and exemplifies a trend toward chronic conditions, such as obesity, becoming health problems in countries emerging from poverty.
Chile was chosen for the experiment because it has most rapidly modernized in terms of nutrition, Ludwig and his colleagues said, noting the irony that “in developed countries, and progressively in developing countries … malnutrition often coexists with excess energy intake and leads to obesity.”
In Chile, the prevalence of stunted growth in children dropped from 10 percent in 1985 to 2 percent in 2002. At the same time childhood obesity was rising from 5 percent to 18 percent.
In the randomized clinical trial that began with 98 overweight or obese boys and girls age 8 to 10, researchers provided half the sample with daily deliveries of milk products, with the proviso that the children drink three glasses a day and abstain from sugar-sweetened beverages (SSBs) like soda and fruit juice. The other half continued to consume beverages as they had before.
After 16 weeks, the milk drinkers showed increased protein and calcium levels but less energy intake. The soda and juice drinkers continued with their usual regimen, including milk, and showed increased protein levels but no change in calcium or energy intake.
Although the researchers looked for a difference in percentage of body fat between the groups, they did not find it, and the significance of the milk drinkers showing decreased energy intake “is not readily apparent.”
But they did find that “accretion of lean mass was greater in the intervention groups than in the control group … For boys, but not for girls, height increases more in the intervention group than in the control group,” the study said.
Ludwig suggested that whey and casein, the main proteins in milk, have contrasting effects when they metabolize and thus could lead to higher lean mass but no change in overall weight. At the same time, the high sugar content of the sodas and fruit juices may cause hormonal actions that suppress creation of lean body mass.
The findings are in line with previous U.S. studies that indicate SSBs and other refined carbohydrates leave a person feeling hungrier than whole foods, like milk, with more nutrients.
The significance of these findings, Ludwig said, is, “If children don’t reach their full growth potential, there is no way to compensate for that in the future … Policy makers could take these findings as a warning sign as to the systemic effects of poor diet quality, above and beyond body weight."
“Effects of replacing the habitual consumption of sugar-sweetened beverages with milk in Chilean children.” Cecilia Albala, Cara B. Ebbeling, Mariana Cifuentes, Lydia Lera, Nelly Bustos and David S. Ludwig. The American Journal of Clinical Nutrition. Vol. 88, No. 3, 606-611, September 2008.