Calcium does not seem to help teenagers lose weight, suggests study.
In the study, more than 40 overweight teenagers were split into two groups and then randomly assigned to consume 1,300 or 650 milligrams of calcium a day.
It either came from calcium supplements or was hidden in foods like frozen chocolate desserts containing milk proteins, fats and minerals (as opposed to whole milk).
For three weeks, both groups were placed on the same restricted diet of three meals and two snacks a day. Both groups got normal foods with enough protein, carbohydrates, fat and calories to maintain their weight.
After a break, the groups resumed the experiment for another three weeks, with teens assigned to a different calcium intake level for the second stage.
In the end, researchers found no differences in body fat and weight between the two groups, suggesting calcium had little to no effect on weight loss among the teens.
"The last 10 years of research hinted that calcium would bind to fat and take some of the fat out so you wouldn't absorb it," Fox News quoted co-author Connie Weaver, a nutrition professor at Purdue University, as saying.
"We showed that didn't happen."
They also tested the amount of calcium and fats the teens excreted and found no indication that calcium might help with weight loss by binding to fat in the intestines and preventing it from being absorbed.
Zemel suggested the findings may have been different because teenagers have different dietary needs than adults.
The study has been published in the American Journal of Clinical Nutrition.