August 20, 2010 | Source: CNN

LONDON, England (CNN) -- Healthy diets almost always contain fish, a protein food with fewer calories than other meat sources. It's also one of nature's most versatile foods. As well as different species of fish, you can steam, bake, fry or poach fish. It's great raw in the form of sashimi, anchovies, carpaccio and gravlax. But there have been conflicting health messages around the benefits of eating fish.

Long regarded as low in fat and high in "good fats," the health benefits have been overwhelmed by concerns about the environmental problems caused by over-fishing and health risks caused by pollutants. 

But last October the Harvard School of Public Health reviewed existing studies that looked at the health effects of eating fish -- and the jury's come back in favor of... eating fish!

The Harvard study recommended eating up to two portions of fish a week and that eating fish could cut the risk of death from heart disease by a third. The evidence across different studies showed that fish consumption lowers the risk of death from heart disease by 36 percent.

The oils in some fish appear to reduce the blood from clotting by reducing the stickiness of the blood. The most beneficial fish in this context is oily fish such as salmon or mackerel. The researchers also suggested that eating that amount of fish or fish oil intake reduces total mortality by 17 percent.

Studies have shown that fish alleviates a range of ailments.

Prostate cancer: A Swedish study of 6000 men over 30 years show that men who did not eat fish between double and trebled the risk of developing prostate cancer compared to those that did. Fish also contains selenium, thought to have cancer-fighting properties.

Depression: The omega-3 fatty acids contained in fish are believed to raise levels of the brain chemical serotonin, which aids in reducing depression. Skin: Some dermatologists say that a salmon rich diet acts like a facial -- smoothing out age lines.

Inflammation: Omega 3 fatty acids, through several mechanisms, regulate your body's inflammation cycle, which prevents and relieves painful conditions like arthritis, prostatitis and cystitis. Fish rich in Omega 3 fatty acids includes, mackerel, trout, herring, sardines, tuna and salmon.

Be sure to contact and discuss eating seafood with your doctor. This is not medical advice. 

For more information on seafood and pregnancy and many other topics, please feel free to visit the National Oceanic and Atmospheric Administration (NOAA) web site here.