When Eating Fish Increases Stroke Risk

Eating fish is good for your heart, since it is a good source of heart healthy omega-3 fatty acid. But a new US study suggests it's not only how much fish you eat that matters, but how it's prepared - and the wrong technique could be a recipe for a stroke.

The southeastern United States is known as the stroke belt. People there have a 20-to-40 percent increased risk of dying of stroke - an interruption of blood supply to the brain usually caused by a blood clot.

Now an ongoing study of almost 22,000 Americans points to a possible culprit: fried fish.

While many people in the stroke belt states were likely to eat two or more servings of fish per week, the fish was often fried in oil, adding calories, fat and increasing cholesterol content. Consumption of fried fish was especially high among African-Americans, who ate it three-and-a-half times more often than Caucasians. Blacks have a higher risk of stroke than whites, no matter where they live.

The American Heart Association recommends people eat fish high in omega-3 fatty acids at least twice a week, baked or grilled - but not fried.

Cooking fish in oil reduces the heart-healthy benefit, according to Virginia Howard of the University of Alabama in Birmingham, one of the study's senior authors.

"Frying the fish takes out the healthy omega-3 fatty acids that are best that we get from fish.  So maybe we need to look at a different cooking method for fish."

The research is part of a large, government-funded study aimed at determining regional and racial differences for heart disease and stroke. Participants filled out a questionnaire which asked how often they ate oysters, shellfish, tuna, fried fish and non-fried fish.  

Howard also says people in the stroke belt may not be eating fish with a high omega-3 fatty acid content, such as salmon, shark and sword fish.
"Certain types of fish are better for frying than others and it could also be that the healthier fishes aren't used for frying."

Howard says she and her colleagues will continue to follow study participants to see if they suffer any strokes and whether any connections can be made to their diet.

The study implicating fried fish and stroke is published in the journal Neurology.