Adequate protein intake important for older women

By Amy Norton

NEW YORK (Reuters Health) - Older women's muscle-building machinery may be less responsive to food compared with men their age -- suggesting they should be sure to get enough protein in their diets, according to researchers.

In a study of 29 adults, 65 to 80 years old, British and U.S. researchers found that men's muscle-protein synthesis increased, on average, after they had a liquid meal, but the same was not true of women.

It's known that age-related muscle loss can contribute to frailty, disability and disease, with women being at greater risk of problems because they have less muscle to begin with.

The new findings, reported in the online journal PLoS One, point to "mechanistic differences" between men and women when it comes to muscle loss.

What's more, the findings suggest that older women, in particular, should be sure to eat adequate protein, from foods like eggs, fish and lean meat, according to the researchers.

Although, on average, women's rate of muscle-protein synthesis did not increase in response to the liquid meal, some of the women did show a small increase, noted Dr. Bettina Mittendorfer of Washington University School of Medicine in St. Louis.

In addition, she told Reuters Health, the test meal contained a relatively modest amount of protein, which may have been inadequate to boost muscle-protein synthesis in some women.

Therefore, Mittendorfer said, "we recommend that women get plenty of protein in their diets."

She pointed out that other research suggests that exercise might boost the response of muscle to food. However, it is not yet clear whether a combination of extra protein and regular exercise can help older women hang on to more muscle. Mittendorfer said she and her colleagues plan on studying this question.

SOURCE: PLoS One, March 2008.