More Good News About Fish

Sept. 19, 2006 — -- The number of kidney cancer cases in the United States has increased, but something in the water might help to slow that down.

Between 10,000 and 13,000 Americans die of kidney cancer every year. The number of new cases has risen by 2 percent every year for the past 65 years, and scientists don't know if that number will keep growing.

But new research suggests that forkfuls of specific fish could save some women from ever getting kidney cancer.

Women might reduce their kidney cancer risk by eating certain fatty fish, according to new research published in today's issue of the Journal of the American Medical Association.

Swedish researchers looked at data from the Swedish Mammography Cohort, a study that began in 1987 when more than 90,000 women were offered a free mammogrram. Researchers questioned them about their diet, drinking habits, weight, height and education. They received detailed information on 61,433 women between the ages of 40 and 76, who hadn't received a cancer diagnosis before the study began.

The study followed the women for an average of 15 years. It found that women who ate one or more servings of fatty fish every week had a 44 to 74 percent lower risk of getting kidney cancer than those who didn't eat that type of fish.

The good-for-you high-fat fish that most women in the study ate were salmon, herring, sardines and mackerel.

However, all types of fish don't protect against cancer.

The researchers also looked at overall fish-eating and found that eating leaner varieties, such as cod, tuna, fresh water fish and shellfish like shrimp and lobster made no difference.

Researchers speculate that the high levels of omega-3 fatty acids and vitamin D in fish oil help protect against cancer.

Laboratory studies have shown these compounds might actually slow cancer cells down and block their ability to reproduce. If cancer cells can't reproduce, they can't multiply and the cancer can't grow or spread.

Scientists are not sure yet whether taking fish oil or vitamin D supplements would have the same effect.

More research might answer that question. Scientists also hope that more research will strengthen the connection between eating fatty fish and preventing kidney cancer.