A Fat That Can Help Your Heart? Sounds Fishy, but It’s True

Last week’s breaking nutrition news was that eating fatty fish once a week lowers the risk of heart disease. But aren’t we supposed to be avoiding fatty foods?

Confused? There’s no need to be. Evolving research shows that fish is heart-healthy food and that the “scientific process” is working just the way it’s supposed to.

The fish-heart disease connection is being explored because large population studies show that countries where people eat a lot of fish have lower heart disease rates. So researchers want to know whether this is a coincidence or if fish has a protective effect. That’s not easy to figure out.

What’s emerging in the fish story is that it’s the fat, not the flesh of the fish, that provides the benefits. This most recent study shows higher-fat fish have the greatest protective effect, and that fits with the body of information that’s been evolving. This seems to contradict our current low-fat focus, but the difference is in the details.

The fat we’ve been fighting is the saturated kind, found primarily in animal products such as whole milk, cheese and yogurt, as well as in meat and poultry products. Diets high in saturated fat tend to cause a rise in blood cholesterol, which is then deposited on arterial walls.

This buildup narrows arteries, creating a trap for small floating blood clots that can get stuck, blocking blood flow. If this happens in your brain, it’s called a stroke. If it happens in your coronary arteries, it’s a heart attack.

Fish fat is different. It contains polyunsaturated omega-3 fatty acids, which indirectly reduce the sticking quality of blood-clotting platelets. Diets high in omega-3 fatty acids tend to produce fewer blood clots.

This new study adds another puzzle piece. Apparently the omega-3 fatty acids also get incorporated into red blood cell membranes themselves, changing the way they function. Exactly how is yet to be uncovered. (And that’s the scientific process--for every question answered, dozens more arise.)

When it comes to balancing the total fat in your diet, this study again agrees with current guidelines. While the focus is on higher-fat fish, the portions are small. One three-ounce portion each week can make a difference.