January 16, 2006

Calcium supplements don’t help girls lose fat

By Charnicia Huggins

NEW YORK (Reuters Health) - Girls who normally consume lots
of calcium in their diet have less body fat than their peers,
but those who add calcium supplements to their diets do not
lose fat or weight, new study findings show.

The current results are "extremely clear cut that there is
absolutely no effect of calcium supplements on body fat and
body weight," study author Dr. Arne Astrup, of the Royal
Veterinary and Agricultural University in Denmark, told Reuters

"It is possible that the effect of calcium on body weight
is only exerted if it is ingested as part of a meal," Astrup
and his co-authors speculate "or the effect may be due to other
ingredients in dairy products, and calcium may simply be a
marker for a high dairy intake."

Various researchers have found that people who report an
increased intake of calcium or an increased intake of dairy
products have lower body weights than those who consume less
calcium or dairy products. One study showed that adults who
consume higher amounts of calcium may have a lower risk of

Yet, such researchers may not have taken into consideration
other factors that may explain the association between calcium
and body weight, the current report suggests.

Previous research conducted among 8-year-old boys, for
example, showed that a high protein intake from skim milk
stimulated their bodies to produce insulin-like growth factor
and insulin, which is known to be involved in regulating one's
appetite. What's more, studies have shown that milk protein
increases a person's sense of satiety, or that feeling of being

To investigate, Astrup and his colleagues analyzed findings
from a study conducted among 110 girls, who were all about 12
years old. Based on a food frequency questionnaire completed by
the girls, they were divided into a median-calcium group, who
reported consuming up to 1,304 milligrams of calcium every day
or a low-calcium group that consumed less than 713 milligrams
per day.

Girls from both groups were randomly assigned to receive
500 milligrams per day of a calcium supplement or placebo
tablets for a year.

By the end of the study girls who had taken calcium
supplements had not experienced any related changes in height,
body weight, or percentage body fat, the researchers report in
the American Journal of Clinical Nutrition.

Yet, those who reported consuming higher amounts of dietary
calcium at the start of the study, who were initially placed in
the median-calcium group, had less body fat both at the start
and at the end of the year-long study period, than did girls in
the low-calcium group, the study findings indicate.

How dietary calcium, rather than supplementary calcium,
decreases body fat may be related to the "timing of the intake
of calcium and the intake of fat," Astrup said. Supplements
taken in the morning or at night are "probably absorbed before
you have any food," he said, explaining that calcium "binds to
fatty acids," and so must be taken with meals.

Exactly how much weight someone can lose by increasing his
or her calcium intake is unknown, but research suggests it "can
be a weight loss of two kilos per year," Astrup said.

"It could be quite nice to simply lose weight by having
some more skim milk every day," the researcher said. What's
more, drinking half a liter of low-fat milk products every day
may not only help in regulating one's weight, but has numerous
other benefits, including healthier bones, lowered blood
pressure and decreased colon cancer risk, he added.

SOURCE: American Journal of Clinical Nutrition, January