Cutting Fat is No Cure-All for Older Women in Study

By BOB GROVES, STAFF WRITER

Older women who followed a low-fat diet did not reduce their risk of cancer and heart disease, researchers in the largest study of its kind said Tuesday.

A diet low in fat and heavy on fruit and vegetables had no effect on the rates of colorectal cancer, heart disease or stroke for post- menopausal women, the study found. Older women who ate less fat slightly reduced their rate of breast cancer, but the difference was not large enough to be considered statistically significant, or more than simply chance.

The clinical trials at 40 sites, sponsored by the federal Women’s Health Initiative, followed 48,835 women, between the ages of 50 and 79 years old, for eight years. The results of the $415 million study are published today in the Journal of the American Medical Association.

The study appears to challenge the conventional wisdom that reduction of fat would reduce the risks of breast and colorectal cancers and have a positive impact on heart disease.

But this should not encourage women to throw low-fat dietary caution to the winds, said Dr. Norman L. Lasser of the University of Medicine and Dentistry of New Jersey.

“I don’t think it’s time to tell women to eat high fat” foods, said Lasser, a preventive cardiologist UMDNJ-New Jersey Medical School in Newark. He headed the study at UMDNJ, which followed 1,800 of the women in the research project.

“It’s not pig-out time. It’s time to do whatever you can” to continue sensibly monitoring fat intake, he said.

A sub-group of women in the study who started with the highest- fat diets and then cut back on fat showed a 12 percent reduction in breast cancer, he said. And researchers also found that women who ate low amounts of the worst kinds of fats suffered less heart disease.

The low-fat group also reported fewer colon polyps, but those results were inconclusive because polyps generally take 10 years to become cancerous, Lasser said.

The diet study has received more funding and will continue another five years, he said.

“My personal opinion is we are going in the right direction,” Lasser said.

The research involved post-menopausal women who either cut overall fat consumption and increased vegetables, fruits and grains, or who continued their usual eating habits. Cancer and heart disease incidence was similar in both groups.

The study was designed mainly to investigate breast cancer risk. Dietary fat was thought to be implicated because breast cancer rates are high in Western countries with fatty diets, but recent studies have failed to show any relationship, said Dr. Michael Thun of the American Cancer Society.

Another target was colon cancer, which some studies have linked with red meat.

Researchers suggested that the women in the study may have begun their healthy eating too late in life. Most remained overweight, a major risk factor for cancer and heart problems.

One of the reasons the women did not enjoy better health benefits is they failed to cut enough fat out of their diet, according to the researchers.

The women on the low-fat diet consumed an average 24 percent to 29 percent of their calories from fat, but never made the study’s goal of 20 percent calories from fat.

Federal guidelines recommend that adults keep their total fat intake between 20 percent and 35 percent of calories, and saturated fats less than 10 percent of calories. The study did not differentiate between “good fats” found in fish, nuts, meats and vegetable oils, and “bad fats” such as saturated fat and trans-fat in processed foods, meats, and some dairy products.

Dr. Elizabeth G. Nabel, director of the National Heart, Lung and Blood Institute said results of the study do not change established recommendations on disease prevention.

“Women should continue to get regular mammograms and screenings for colorectal cancer, and work with their doctors to reduce their risks for heart disease,” including following low-fat, low- cholesterol diets, Nabel said in a statement Tuesday.

Lasser agreed that more study is needed.

“We’d much rather have highly significant results,” Lasser said.

But for now, “following a low-fat diet won’t hurt you, but it may help you is all we can say.”

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(SIDEBAR)

Too little, too late

A low-fat diet did little to cut risk of breast and colon cancer and heart disease in older women, a study found.

Why it failed: Researchers speculate the women changed their diets too late in life. They also didn’t cut out enough fat.

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This article contains material from The Associated Press.

E-mail: groves@northjersey.com