NEW YORK, Oct 25 (Reuters Health) - Eating tuna, salmon, or other fish rich in omega-3 fatty acids once a day as part of a weight-loss plan can help you lose weight and improve your overall health, Australian researchers report.

Cold water fish such as salmon, tuna, cod and mackerel are rich in omega-3 fatty acids. Research suggests that omega-3's protect against heart disease by lowering blood pressure and cholesterol levels.

In a 4-month study of 69 overweight men and women who were being treated for high blood pressure, participants who ate a daily serving of fish rich in omega-3 fatty acid as part of a weight-loss regimen lost weight, lowered their cholesterol levels and reduced their risk factors for diabetes, compared with participants who either just ate fish once a week, only participated in a weight loss plan, or those in a 'control' group who maintained their usual eating habits.

"This dietary approach conferred greater benefits than did a fish diet or a weight-loss program alone," lead researcher Trevor A. Mori of the University of Western Australia and colleagues report in the November issue of the American Journal of Clinical Nutrition. "Cardiovascular risk is likely to be substantially reduced in overweight (people with high blood pressure) with a weight-loss program incorporating fish meals rich in omega-3 fatty acids," they add.

To arrive at their findings, the researchers asked study participants to either eat fish containing 3.65 grams of omega-3 fatty acid once a day, follow a low-fat weight-loss plan, follow a combined version of these two regimens, or maintain their usual eating habits. They followed participants for about 16 weeks to see how the eating plan affected their blood cholesterol levels, weight, and diabetes risk profile.

Participants who ate a daily serving of fish as part of their weight-loss plan saw the greatest improvements in all measures, the investigators found.

Eating fish once a day is "likely to substantially reduce risk of cardiovascular disease in obese patients," Mori and colleagues report. Obesity is a major risk factor for heart disease.

The researchers note that study participants who ate fish daily had the greatest drop in blood fats that increase the risk of heart disease, and the greatest rise in HDL cholesterol -- the "good" cholesterol linked to a lower risk of coronary artery disease.

The authors note that fish oil supplements sold in most health food stores provide another option for people who don't like fish. "However, daily fish consumption offers greater dietary benefits because as fish consumption increases, meat consumption likely decreases, resulting in a decrease in saturated and total fat intakes," they conclude.

Sources

American Journal of Clinical Nutrition 1999;70:817-825.