A meta-analysis hints that the effects of a low-fat diet on serum lipids in women are greatest during the premenopausal years. After menopause, the effects of low-fat diets on lipids are less clear.
The findings “seem to be important from a practical perspective, especially for premenopausal women,” the study team says. “Based on our results, providers should suggest that women adopt a low-fat diet before menopause to improve serum lipid levels,” regardless of their current lipid levels, they advise.
Dr. Zhong He, from Peking Union Medical College, Chinese Academy of Medical Science in Beijing and colleagues included in their analysis eight randomized controlled trials that compared the effects of low-fat vs usual diets in 1,536 pre- and postmenopausal women.
The results overall, they say, suggest that low-fat diets are highly effective at reducing concentrations of total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein (LDL-C), but not triglycerides (TG) or TC-to-HDL-C ratio in women.
But the subgroup analysis found differing effects by age. Low-fat diets reduced TC, HDL-C, and LDL-C in premenopausal women but had no significant effect on TC, HDL-C, and LDL-C in postmenopausal women, Dr. He and colleagues report.
“Low-fat diets are defined as diets aiming at energy intake with 30% or less of energy derived from fat (saturated fat, unsaturated fat, or both). A low-fat diet is a simple low-cost lifestyle change that has been recommended for improving lipid concentrations in women,” the researchers note.
They say, until now, there haven’t been any meta-analyses focusing on the effects of a low-fat diet on women and, more specifically, on premenopausal and postmenopausal subgroups. In addition, the TC-to-HDL-C ratio – which is considered “more important” than TC or lipoprotein cholesterol concentrations in estimating the risk of heart disease – was “seldom” assessed in previous studies.
Based on their findings, they say women should be advised to follow a low-fat diet before they reach menopause. They say additional studies are needed to further address the effects on postmenopausal women and the duration of low-fat diets in women.
The study was published online June 3 in Menopause: The Journal of the North American Menopause Society. It had no funding support and the authors have no conflicts of interest. They did not respond to a request for comment by press time.
— NEW YORK (Reuters Health)0