BALTIMORE – In a season of ritual overeating, researchers at Johns Hopkins University have come up with another reason for men to watch their diets: Low cholesterol might protect them from the most aggressive form of prostate cancer.
This isn’t the first time medical researchers have linked fats to cancer and its consequences. Recent studies have linked obesity to higher death rates from several types of the disease, and a previous Hopkins study found that men on cholesterol-lowering drugs were less likely to develop fast-growing prostate tumors.
Now, researchers led by epidemiologist Elizabeth Platz are reporting that men in a study with low cholesterol were one-third less likely to get high-grade prostate cancer – the type that tends to grow quickly and spread.
The research, presented at a recent meeting of the American Association for Cancer Research in Boston, was part of an ongoing Harvard University study of 18,000 health professionals.
In 1993, researchers asked the men to submit blood specimens through the mail. More than 18,000 did so, and their specimens were put in cold storage. Later, the researchers identified 700 men who developed prostate cancer and compared their blood with that of 700 men without evidence of the disease.
The scientists found no difference in the cholesterol levels of men with and without prostate cancer. But they did discover that men with low cholesterol were less likely to get aggressive cancers.
“What we’re thinking is that cholesterol doesn’t seem to influence the initial development of the disease,” she said. “Maybe it affects the progression of the disease and the differentiation status” – alterations in the appearance of prostate cells when they become aggressively cancerous.
Men with high-grade prostate cancer are also more likely to suffer a recurrence after having their prostates surgically removed.
According to Platz, men do not have to be concerned about lowering their cholesterol to abnormal levels. Those less likely to develop aggressive tumors had cholesterol levels in the same range considered healthy for the cardiovascular system.
Men whose cholesterol levels were no greater than 165 milligrams per deciliter of blood had the lower rates of high-grade prostate cancer. Platz warned, however, against interpreting this as a benchmark, saying the threshold differed from one subgroup to another.