| NEW YORK
NEW YORK (Reuters Health) - Women who want to get pregnant
may want to stay away from fast food French fries not just to
avoid putting on some extra pounds, a new study shows.
The more trans fats a woman eats, the more likely she is to
be infertile, Dr. Jorge E. Chavarro of the Harvard School of
Public Health in Boston and colleagues found.
Trans fats are found in fried foods, packaged snacks,
commercial baked goods and other sources, and are known to
increase the risk of heart disease and diabetes. "Even for
somebody who's not trying to get pregnant, it is a very good
idea to stay away from them," Chavarro told Reuters Health.
Trans fats can interfere with the activity of a cell
receptor involved in inflammation, glucose metabolism and
insulin sensitivity, Chavarro and his team note in the American
Journal of Clinical Nutrition. Drugs that activate the receptor
have been shown to improve fertility in women with a condition
known as polycystic ovary syndrome.
To investigate how trans fat consumption might affect
fertility, the researchers analyzed data from 18,555 healthy
women participating in the Nurses' Health Study. All were
married and trying to get pregnant between 1991 and 1999.
For every 2 percent increase in the amount of calories a
woman got from trans fats instead of carbohydrates, the
researchers found, her risk of infertility increased by 73
percent. The risk rose by 79 percent for every 2 percent of
energy in trans fats if they replaced omega-6 polyunsaturated
fats. And for every 2 percent of calories derived from trans
fats instead of monounsaturated fats, the risk of infertility
more than doubled.
For a woman eating 1,800 calories a day, 2 percent of
energy intake in trans fats equals 4 grams, Chavarro noted.
"It's not very hard to get 4 grams of trans fatty acids every
day," he said. "It's really a small amount of trans fatty acids
that we observe having a significant effect on infertility."
The Food and Drug Administration now requires manufacturers
to state on their label if a food contains a half gram of trans
fat per serving or more, Chavarro noted, but foods with less
than a half gram are allowed to claim that they have zero grams
of trans fat. To cut trans fats out of the diet completely, he
added, people should avoid all foods that list hydrogenated or
partially hydrogenated oils in their ingredients.
SOURCE: American Journal of Clinical Nutrition, January