you can try but only for short term...long term high doses may have negative effects such as bone damage
Vitamin A 'broken bones risk'
January 23, 2003
TAKING vitamin A supplements can weaken the bones and increase the risk
of fractures up to seven times, according to a large Swedish study.
The research, conducted on men, confirms three earlier studies in women
showing that high intake of vitamin A raises the risk of broken hips and
The latest study is the first to measure levels of the vitamin in blood,
rather than just asking about diet and supplement use.
The three-decade study and other evidence suggest that daily vitamin A
consumption of more than 1.5 milligrams can be dangerous, and that
people should not take vitamin A supplements.
Present dietary recommendations call for only 0.7 mg of vitamin A for
women and 0.9 mg for men a day. That is easily supplied by a healthy
diet. But many popular multivitamins contain 0.75 mg to 1.5 mg of
vitamin A, generally listed on labels as 2,500 international units and
5,000 IUs, respectively.
"Vitamin A is potentially harmful," Dr Donald Louria, chairman emeritus
of preventive medicine at the University of Medicine and Dentistry of
New Jersey in Newark, said.
"Unless there is a known medical reason like certain diseases of the
eye, ... people should not be taking vitamin A supplements."
The study by doctors at University Hospital in Uppsala is reported in
tomorrow's New England Journal of Medicine. It involved 2322 men.
Vitamin A is known as an antioxidant. Antioxidants are believed to
reduce the risk of cancer and heart disease. Government studies show
one-third to one-half of Americans take vitamin A or multivitamins
Vitamin A can interfere with cells that produce new bone, stimulate
cells that break down old bone and interfere with vitamin D, which helps
the body maintain normal calcium levels.
In the study, about one-fifth, or roughly 465 of the men, were found to
be at risk because they had the highest levels of vitamin A. The men
were about two-and-a-half times more likely to break a hip and 65 per
cent more likely to suffer any fracture than those with lower levels of
the vitamin in their blood.
Those in the 99th percentile were about seven times more likely to break
Louria said that people should not take fish oil supplements or eat
liver more than once a week, but that multivitamins containing 0.1 mg or
less of vitamin A are fine for people eating a healthy diet.
Large amounts of vitamin A are found in beef liver and fish liver oils;
smaller amounts are in egg yolks, butter and cream. Milk and some
cereals are fortified with vitamin A and, per serving, provide about 10
per cent of daily needs. And substances in dark green, leafy vegetables
and yellow vegetables and fruits are converted to vitamin A in the body.
The Associated Press