Philadelphia ? A popular herbal treatment called black cohosh is practically ineffective at relieving hot flashes and night sweats in women going through menopause, a study found.

The findings were disappointing news for women seeking alternatives to estrogen-progestin hormone supplements, which have been linked to breast cancer and heart problems.

The yearlong study of 351 women suffering from hot flashes and night sweats found that those given black cohosh experienced about the same amount of relief as those who took a placebo. And those groups saw nothing close to the improvement in women on hormones.

“It’s safe and not effective, so therefore it doesn’t have any utility whatsoever,” said Barrie Cassileth, an alternative-medicine researcher at Memorial Sloan-Kettering Cancer Center in New York, who was not involved in the study.

The study was conducted at Seattle-based Group Health, a health plan, and was published Monday in the Annals of Internal Medicine.

Black cohosh – an herb that is a member of the buttercup family and is commonly given to ease menopause symptoms – is available in pill or liquid form and is sold over the counter in many health food stores and over the Internet.

In the study, some participants were given black cohosh, while others received hormone supplements, a placebo or a botanical treatment that included black cohosh, alfalfa, licorice and ginseng.

Women taking the herbal treatments reduced hot flashes by only about half an episode per day when compared with those taking the placebo, the study found. Those who received hormone therapy reduced their hot flashes by about four episodes per day compared with the placebo.

“It’s disappointing news,” said Katherine M. Newton, an epidemiologist who helped lead the study, funded by the National Institute on Aging and the National Center for Complementary and Alternative Medicine. “It would be nice to offer something safe and effective.”