Calorie Restriction Lowers Breast Cancer Risk
Study Offers Clues About the Role of Early Diet in Disease
March 10, 2004 -- New research shows that restricting calories
early in life can help decrease breast cancer risk later on.
Animal studies have long linked severe calorie restriction to a
decrease in cancers and other diseases, and the new study is one of the first
to indicate that the same may be true for humans. The findings may also help
explain why malnourished women in developing countries have less breast
Researcher Karin Michels, ScD, from Boston's Brigham and
Women's Hospital and Anders Ekbom, MD, PhD, from Stockholm's Karolinska
Institute tested the theory by comparing breast cancer frequency among women
who had a history of anorexia nervosa with women with no history of the
potentially life-threatening eating disorder.
The women who had been treated for the eating disorder
developed half as many breast cancers, and the reduction in breast cancer risk
was even greater for women who went on to have a child. The study is reported
in the March 10 issue of TheJournal of the American Medical
Early Diet Appears Important
The researchers say their findings show that early diet --
around puberty and young adulthood -- can play an important role in later
breast cancer risk. But they are quick to point out that the findings do not
mean that starvation diets are healthy for young women or anyone else.
"Anorexia nervosa is a very serious condition that is
potentially life threatening," Michels tells WebMD. "It has been linked
to an increased risk for osteoporosis and other health problems, and we are
definitely not advocating starvation diets to lower breast cancer
Being overweight, especially after menopause, is strongly
associated with an increase in breast cancer risk. Newly published research
shows that women can lower that risk by maintaining a healthy body weight
throughout their lives, American Cancer Society spokesman Len Lichtenfeld, MD,
"The message we need to be sending to young women is to
watch their diets, exercise, and maintain a healthy body weight,"
Lichtenfeld says. "But the message is the same for older women and men. We
now know that obesity increases the risk of many different cancers, including
One limitation to the study, Lichtenfeld says, is that it says
little about the impact of early diet on breast cancer risk among the largest
group of women -- those who develop the disease after menopause. Most of the
women in the study were diagnosed before they reached menopause.
Michels says she chose women with a history of anorexia for her
study because the group represented a unique human model of extreme, prolonged
calorie restriction early in life.
The researchers are not recommending anorexia as a means of
preventing breast cancer. About 6% of people with severe anorexia die from
their disease, according to the National Association of Anorexia Nervosa and