Acid, Vitamin B6 May
Protect Against Breast Cancer
from the Harvard School of Public Health have found that a diet
high in folic acid and vitamin B6 can lower a woman's risk of
The results suggest that women
who want to protect themselves against breast cancer should
have a diet high in these nutrients. Women who drink should pay
particular attention to their folic
acid intake, the researchers said, because folic acid appears
to protect them against the increased risk of breast cancer caused
The report appeared in the Journal
of the National Cancer Institute (Vol. 95, No. 5: 373-380).
Folic acid and vitamin
B6 are important parts of our diets. They help make DNA, which
is the basic chemical in genes. Folic acid is found mainly in
dark green leafy vegetables, legumes, citrus fruits and juices,
fortified breakfast cereals, and of course, vitamin supplements.
Vitamin B6 is found in meat, poultry and fish, as well as in fortified
cereals, potatoes, bananas and some beans.
Several studies in the past have
linked a diet high in folic acid to a lower risk of breast cancer.
Because alcohol interferes with the body's ability to use folic
acid, the extra folic acid seems to be most protective in women
But most of these earlier studies
were marred by the fact that they questioned the women about their
diets after they got their cancer, and memory can be faulty. Harvard
researchers Shumin Zhang, MD, and Walter Willet, MD, and colleagues
took a different approach by evaluating women in the Nurses' Health
Study prospectively -- before they developed any problems.
Study Looks At Lifestyle
And Breast Cancer
The Nurses' Health Study began
in 1976, enrolling 121,700 female registered nurses. The study
was intended to look at lifestyle risk factors for many different
diseases in women. At the beginning of the study and periodically
afterwards, the nurses were asked about their diets, lifestyle,
and whether they took vitamins. They were also surveyed for any
change in their health; more than 32,000 of the nurses also gave
blood samples from time to time.
The researchers compared 712 of
these nurses who developed breast cancer with 712 nurses who didn't
get breast cancer. They found that the nurses with breast cancer
had a diet that contained less folic acid and they had lower levels
of folic acid in their blood.
The researchers also found that
although high folic acid intake reduced breast cancer risk in
all the women, it was most protective in those who drank more
than one drink a day. It reduced the higher risk caused by their
The researchers also examined the
intake of two vitamins, B6, and B12, because they, too, are involved
with making DNA. Although B12 was not protective, B6 was. Women
with a higher intake of B6 and higher blood levels of this vitamin
had a lower rate of breast cancer. And the B6 was as beneficial
in non-drinkers as well as drinkers.
However, experts said it's too
soon to make new recommendations about nutrient intake for prevention
of breast cancer.
The data so far shows only an association
between nutrition and cancer risk, not a cause and effect, said
Debbie Saslow, PhD, director of breast and gynecological programs
for the American Cancer Society. Furthermore, she said, other
recent studies have not found the same association between folate
and breast cancer as this one.
"We don't have good answers yet,"
Saslow said. "But we know that following ACS
guidelines for nutrition and physical activity is good for
your health overall - for different types of cancer and other
Breast cancer is the second leading
cause of cancer deaths among American women. The American Cancer
Society estimates that more than 211,000 women will get breast
cancer this year, and nearly 40,000 will die from it.
breast self-examinations and examinations by a doctor can help
detect breast cancer early. The ACS recommends yearly mammograms
and breast examinations by a doctor for all women over age 40.
Women between the ages of 20 and 39 should have a doctor do a
breast exam every three years, and all women over 20 should do
Reference Source 102