More on the low-fat story
Fighting cancer with aspirin

More on the low-fat story

Landmark Women's Health Initiative study of nearly 50,000 postmenopausal women indicates a low-fat diet may reduce breast-cancer risk, but shows little impact on colon cancer or heart disease

BY KRISTEN WOODWARD

Adopting a low-fat diet in later life and following it for nearly a decade appears to have little impact on reducing the overall risk of breast cancer, colorectal cancer or heart disease, according to a Women's Health Initiative study that involved nearly 50,000 postmenopausal women across the United States.

The study — the first to test the health impact of a low-fat diet in a randomized, controlled trial, considered the gold standard of clinical and public-health study design — did, however, uncover some encouraging trends, according to Hutchinson Center biostatistician Dr. Ross L. Prentice, one of the lead researchers.

"Women in the low-fat-diet group reduced their overall rate of breast cancer by about 9 percent as compared to the women who didn't change their eating patterns, but that difference was not statistically significant; it could have been due to chance. So at this point we're not able to say with certainty that a low-fat diet reduces the risk of breast cancer," Prentice said.

However, women in the low-fat group experienced a 30 percent risk reduction for a certain subtype of breast cancer: tumors known as PR negative. Significant reduction of risk also was seen among women who began the study with the highest baseline fat consumption and among those who strictly adhered to the dietary-fat goals.

"The bottom line is that changing to a low-fat diet may reduce breast-cancer risk, especially among women who have a relatively high-fat diet to begin with, but we don't view our data as strong enough at this time to make a broad recommendation that all women initiate a low-fat diet for that purpose," Prentice said.

With regard to colorectal cancer, the study did not reveal a reduction of cancer incidence overall, but it did show a modest 9 percent decrease in self-reported colon polyps — a precursor to colon cancer — among the women in the low-fat intervention group, said Dr. Shirley A.A. Beresford, of the Hutchinson Center and the University of Washington.

No significant reduction in heart disease emerged among the women in the low-fat intervention group, who achieved only a 2.4 percent reduction in low-density lipoprotein, the so-called "bad" cholesterol, and a 3 percent lower rate of heart disease.

"While the study didn't give us the results that some people were hoping for, it suggests that we're on the right track," Prentice said. "Women can be confident that cutting back on fat and following the recommended Dietary Guidelines for Americans certainly won't hurt when it comes to maintaining a healthy lifestyle and preventing chronic disease."

The Women's Health Initiative

The Women's Health Initiative, the largest study ever devoted to women's health, is a 15-year, multimillion-dollar effort involving more than 161,000 women nationwide. The study focuses on strategies for preventing heart disease, breast and colorectal cancer, and fractures in postmenopausal women. The Hutchinson Center is home to the WHI Clinical Coordinating Center, which oversees the statistical, epidemiologic, nutritional and clinical aspects of the study and is responsible for data collection, management and analysis. Dr. Ross L. Prentice serves as principal investigator of the Clinical Coordinating Center. The Hutchinson Center is also home to one of the WHI's clinical study centers.

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Fighting cancer with aspirin

Regular use of aspirin and other nonsteroidal anti-inflammatory drugs may reduce esophageal-cancer risk for people with Barrett's esophagus

BY KRISTEN WOODWARD

Aspirin, ibuprofen and other anti-inflammatory drugs may significantly reduce the risk of esophageal cancer among people with Barrett's esophagus. The precancerous condition, which is associated with chronic heartburn, affects an estimated 1 million to 2 million Americans.

In the largest and longest study of its kind, Dr. Thomas Vaughan and colleagues studied the impact of nonsteroidal anti-inflammatory drugs, or NSAIDs, on changes in the lining of the esophagus that signal the advancement toward cancer.

"We found that people with Barrett's esophagus who regularly took NSAIDs, like aspirin or ibuprofen, did not go on to get cancer as frequently or as soon as people who did not take these medications regularly," Vaughan said. "Current users of NSAIDs had one-third the risk of getting esophageal adenocarcinoma as compared to never users."

Five years after joining the study, the incidence of esophageal cancer was 14.4 percent among never users, 9.7 percent among former users (those who had used NSAIDs regularly for a year or more prior to joining the study) and 6.6 percent among current users (those who took NSAIDs at least once a week).

Because this was a long-term observational study and not a clinical trial, the investigators cannot recommend NSAIDs for people with Barrett's esophagus and they advise anyone who considers taking these medications for this condition should do so under the direction of a physician.

"If I had Barrett's, I'd be looking for anything that would help, and this is something that might help," said Vaughan, also a professor at the University of Washington. "But since these drugs can have serious side effects, such as gastrointestinal bleeding, this is a decision that Barrett's patients should make with their doctor."

Previous randomized clinical trials have shown that aspirin and other NSAIDs significantly reduce the risk and mortality for cardiovascular disease and colorectal cancer. Preliminary studies also suggest these drugs may be protective against breast and lung cancers. It is thought that NSAIDs may fight cancer by reducing chronic inflammation, which is a driving force behind the development of many cancers and other diseases.

While the risk of developing esophageal cancer in a person with Barrett's is only about 1 percent per year, the outlook is grim if the disease is not diagnosed early. The majority of patients with invasive esophageal cancer die within a year of diagnosis.

"Most Barrett's patients will never get esophageal cancer, but since it is a rapidly fatal cancer once you get it, it's important to identify ways to prevent it," Vaughan said. "This research gives us hope that there may be an inexpensive and relatively safe way to lower Barrett's-related cancer risk."

Managing chronic acid reflux

Dr. Thomas Vaughan and colleagues offer the following suggestions to reduce the symptoms of acid reflux, a major risk factor for Barrett's esophagus:

• Don't smoke.
• Keep your weight down and get regular exercise.
• Eat a diet rich in fruits and vegetables.
• Refrain from eating four hours before bedtime.
• If you're having heartburn, sleep with the head of your bed elevated (ask your doctor how to do this).
• Avoid foods and beverages that promote heartburn, including alcohol, caffeine, chocolate, peppermint, onions, green peppers and foods that are high in fat, all of which can relax the muscle that prevents stomach acid from washing up into the esophagus.
• Take antacids as needed for occasional heartburn. Talk to your doctor if you have frequent heartburn or if over-the-counter medications don't relieve your symptoms.

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