THURSDAY, Nov. 5 (Health.com) — Most people know that healthy cholesterol levels can help protect your heart. But new research suggests another potential benefit: a lower risk of developing some types of cancer.

In fact, low total cholesterol is associated with about 60% less risk of the most aggressive form of prostate cancer, and higher levels of good cholesterol (HDL) may protect against lung, liver, and other cancers, according to two studies published this week in the journal Cancer Epidemiology, Biomarkers & Prevention.

That’s quite a reversal of fortune for low cholesterol, which has, in the past, been associated with a higher cancer risk. The new studies suggest that low cholesterol may not deserve its bad reputation, earned from a series of studies in the 1980s that said people with low cholesterol might be at risk of cancer.

In fact, cholesterol may drop in people with undiagnosed cancer, meaning that low cholesterol may be a result—not a cause—of cancer.

In the first study, men with HDL cholesterol above roughly 55 mg/dL had an 11% decrease in overall cancer risk, including lung and liver cancer. (HDL levels between 40 and 50 are average for men.) The study, conducted by National Cancer Institute (NCI) researchers who looked at about 29,000 male smokers in Finland over an 18-year period, is the largest to show a relationship between HDL and cancer.

“Very few studies measured [HDL], and any relationship between HDL and overall cancer risk had therefore not been adequately evaluated,” the NCI’s Demetrius Albanes, MD, the lead author of the study, said at a press briefing.

While the findings are new and intriguing, more research needs to be conducted to confirm a link between HDL and cancer risk reduction.

“[It’s] a very new, exciting question, but we need to do a great deal more research before we have any clear answers,” says Eric Jacobs, PhD, an epidemiologist with the American Cancer Society, who co-wrote an editorial accompanying the studies. For his part, Dr. Albanes stressed that the results need to be confirmed, especially in women and nonsmokers.

At first, Dr. Albanes and his colleagues found their results seemed to back up the studies from the 1980s; they discovered that men with low total cholesterol had a higher cancer risk. The trend all but disappeared when they excluded cases of cancer that were diagnosed during the first nine years of the study. (Such men may have already had cancer, but it hadn’t been diagnosed yet.)

In the second study, researchers looked at about 5,500 men ages 55 and older. Men with total cholesterol under 200 mg/dL—the range the National Heart, Lung and Blood Institute deems “desirable”—had roughly a 60% lower risk of high-grade prostate cancer, an aggressive type.

“It was a notable reduction, which is not that often seen in prostate cancer research,” the lead researcher, Elizabeth Platz, ScD, a cancer epidemiologist at the Johns Hopkins Bloomberg School of Public Health, told reporters.

The decrease in risk was found only in high-grade tumors and not in less serious cases of prostate cancer—a pattern that Platz and her colleagues reported in a previous, similar study. According to Jacobs, this pattern is not uncommon in prostate-cancer studies. Obesity, for example, is associated with a higher risk of more dangerous tumors but not with prostate cancer overall, he said.

This study was inspired in part by a growing body of evidence that suggests that statins, which are cholesterol-lowering drugs such as Lipitor, may protect against high-grade prostate cancer. In the current study, however, Platz and her colleagues did not measure statin use and therefore were not able to determine whether the lower risk of high-grade prostate cancer was influenced by statins or other cholesterol-lowering methods, rather than naturally low cholesterol.

“Our next step…is to look not just at total cholesterol, but to also evaluate the relationship for high HDL cholesterol and low LDL cholesterol, and also to evaluate whether cholesterol-lowering—rather than low cholesterol as the usual state for these men—would also explain this relationship,” Platz said.

More studies, including randomized controlled trials, are necessary to explain the link between cholesterol and prostate cancer, according to Platz.

Jacobs agreed, noting that the findings of the two studies raise important questions. The effect that HDL cholesterol and total cholesterol have on cancer risk are “likely to be very interesting areas for future research,” he said.

FRIDAY, Dec. 11, 2009 (Health.com) — Doctors have known for years that a woman’s risk of developing heart disease rises after menopause, but they weren’t exactly sure why. It wasn’t clear whether the increased risk is due to the hormonal changes associated with menopause, to aging itself, or to some combination of the two.

Now, we have at least part of the answer: A new study shows beyond a doubt that menopause, not the natural aging process, is responsible for a sharp increase in cholesterol levels.

This seems to be true of all women, regardless of ethnicity, according to the study, which will be published next week in the Journal of the American College of Cardiology.

“As they approach menopause, many, many women show a very striking increase in cholesterol levels, which in turn increases risk for later heart disease,” says the lead author of the study, Karen A. Matthews, PhD, a professor of psychiatry and epidemiology at the University of Pittsburgh.

Over a 10-year period, Matthews and her colleagues followed 1,054 U.S. women as they went through menopause. Each year the researchers tested study participants for cholesterol, blood pressure, and other heart disease risk factors such as blood glucose and insulin.

In nearly every woman, the study found, cholesterol levels jumped around the time of menopause. (Menopause usually occurs around age 50 but can happen naturally as early as 40 and as late as 60.)

In the two-year window surrounding their final menstrual period, the women’s average LDL, or bad cholesterol, rose by about 10.5 points, or about 9%. The average total cholesterol level also increased substantially, by about 6.5%.

Other risk factors, such as insulin and systolic blood pressure (the top number in a blood pressure reading), also rose during the study, but they did so at a steady rate, suggesting that the increases—unlike those for cholesterol—were related to aging, not menopause. Of all the risk factors measured in the study, the changes in cholesterol were the most dramatic.

The jumps in cholesterol reported in the study could definitely have an impact on a woman’s health, says Vera Bittner, MD, a professor of medicine at the University of Alabama at Birmingham, who wrote an editorial accompanying Matthews’s study.

“The changes don’t look large, but given that the typical woman lives several decades after menopause, any adverse change becomes cumulative over time,” says Dr. Bittner. “If somebody had cholesterol levels at the lower ranges of normal, the small change may not make a difference. But if somebody’s risk factors were already borderline in several categories, this increase may tip them over the edge and put them in a risk category where treatment may be beneficial.”

In a first, the study did not find any measurable differences in the impact of menopause on cholesterol across ethnic groups.

Experts have been unsure how ethnicity may affect the link between menopause and cardiovascular risk, because most research to date has been conducted in Caucasian women. Matthews and her colleagues were able to explore the role of ethnicity because their research is part of the larger Study of Women’s Health Across the Nation (SWAN), which includes substantial numbers of African-American, Hispanic, and Asian-American women.

More research on the connection between menopause and heart disease risk is needed, according to Mathews. The current study doesn’t explain how the increases in cholesterol will affect the rate of heart attacks and mortality down the road, for instance.

As the SWAN study continues, Matthews says, she and her colleagues hope to identify warning signs that will show which women are most at risk for heart disease. “The important thing is, ultimately, when we can figure out the characteristics of women who have early signs of cardiovascular risk that, if we don’t do anything about them, could later result in a heart attack.”

Women should be aware of the changes in risk factors that occur around menopause, says Dr. Bittner, and they should talk to their doctors about whether they need to have their cholesterol checked more often or whether they should begin a cholesterol-lowering treatment, such as a statin.

Maintaining a healthy weight, not smoking, and getting plenty of exercise are essential to help keep cholesterol levels in check, Dr. Bittner adds, and she points out that menopause can be an especially difficult time for women to get enough physical activity. “It often falls by the wayside because women in this age range take care of kids, spouse, aging parents, and often work in addition,” she says.

“Midlife is a great time to make these changes,” Matthews says. “If we can essentially reset the course to a more health-promoting direction in midlife, then that will have benefits for many years to come.”

Wolf Ulian, PhD, the founder and executive director of the North American Menopause Society, a nonprofit organization that provides information on menopause to consumers and health-care professionals, says the findings underscore that menopause is a good time for women to adopt healthier lifestyles.

“Menopause is a milestone,” he says. “It’s a time to take stock and take control and try to enhance the quality of your second half of life.”