Fish: The Wonder Food
Author: Liz Applegate Ph.D.
The secret ingredient in fish? Omega-3 fats. Here’s why you need more of them.
Runners often ask me to assess their diets, so I spend a lot of time looking over food diaries. Way too often, I find the same deficiency: not enough fish. That’s a problem, because fish contains a very powerful, almost panacea-like nutrient called omega-3 fats. When eaten regularly, these fats improve physical and mental health, and prolong life. We know that humans once ate much more fish and other sources of omega-3s (wild animals, nuts, berries) than we do today. And while it’s true that our cave brothers and sisters didn’t live as long as we do, they remained largely free of many of the ailments that plague us today, such as heart disease, cancer, arthritis, psoriasis, Alzheimer’s disease, diabetes, and even mental illness. The reason? Quite possibly, because early humans had their fill of omega-3s. So here’s the deal on omega-3s, and how to get more of them for better health.
Often called “good” fats, omega-3s are found mostly in seafood and flaxseed products and, to a lesser extent, in certain oils and nuts. Omega-3 fats are considered essential fats, because our body cannot manufacture them. We can only get them from the foods we eat.
Omega-3s are used to create signaling molecules called prostaglandins that direct blood vessels to dilate, encourage blood to stay fluid, and reduce the inflammation response associated with ailments such as heart disease and psoriasis. Omega-3s also become embedded in various cells throughout the body, making them healthier and more pliable.
Another essential fat, called omega-6, is found primarily in vegetable oils (corn, sunflower, safflower), and also transforms into prostaglandins. But these signaling molecules have an opposite effect to the ones derived from omega-3s. They promote blood clotting, constrict blood vessels, and encourage the inflammatory response. The proper balance of omega-3s to omega-6s prostaglandins is vital for maintaining optimal health and fending off disease.
The amount we need of these two essential fats is not clear, but scientists do know that we generally consume too few omega-3s and too many omega-6s. Some experts advise that we consume 1 to 3 grams of omega-3s daily (a 3-ounce serving of salmon has about 2 grams), but again, the ratio of the two essential fats is the key. Scientists believe that early humans consumed omega-3 and omega-6 fats in an 1 to 4 ratio. Today, because of our heavy use of vegetable oils in cooking, and our skimpy intake of fish and flaxseed, our intake ratio is a frightful 1 to 10.
How Omega-3s Protect Us
By increasing your intake of omega-3 fats, you can significantly lower your risk of certain ailments, and you may boost your brain power. Here’s the latest:
Heart disease. Eskimos brought fish and omega-3s into prominence because heart disease is virtually nonexistent among their population. Further research has shown that regular consumption of fish significantly lowers heart-disease risk. For example, a recent study of 85,000 women found that those who ate two to four servings of fish a week cut their heart-disease risk by 30 percent. It’s been shown that omega-3s lower blood fat levels, boost levels of “good” HDL cholesterol, and keep the blood thin, which makes life-threatening blood clots less likely.
Cancer. Fish and omega-3s may also lower your cancer risk. In a new study, men who never ate fish were twice as likely to develop prostate cancer than fish-eaters. In other studies, cancer risk, particularly of the intestinal tract, is dramatically lower among those who regularly eat fish. Scientists theorize that omega-3 fats may stop cancer-causing agents from entering cells.
Dementia. Age-related decline in brain function comes on slowly, and is caused in part by clogged arteries in the brain. Therefore, a heart-healthy diet may lower dementia risk. And sure enough, a recent study found that those who regularly ate fish had a significantly lower risk of dementia than did non-fish eaters.
Arthritis. Various conditions, including rheumatoid arthritis and asthma, are rooted in the body’s inflammatory response. And since omega-3 fats help curb inflammation, these fats show promise in the treatment of arthritis. Several studies have shown that regularly consuming 2 to 3 grams of omega-3 fats helps decrease joint tenderness and swelling in those with rheumatoid arthritis.
Diabetes. Though diabetes is rampant in the United States because of obesity, poor diet, and inactivity, Eskimos rarely suffer from diabetes. Research suggests their high consumption of omega-3 fats from salmon and seal blubber (admittedly, a bit hard to find in the grocery store) provides them protection from diabetes. The mechanism behind this is simply that omega-3 fats improve insulin’s action, which is great news for those at risk for diabetes.
Depression. Recent studies show that omega-3 supplementation can improve symptoms of a variety of depressive disorders, including bipolar disease and postpartum depression. While omega-3s are by no means seen as a substitute for prescribed medication, the study results are promising nonetheless. Healthy brain cells contain a fair amount of omega-3 fats in their membrane structure, so researchers aren’t surprised about their mood-boosting powers.
Brain power. Since omega-3 fats become part of brain cells, taking in ample amounts of these fats early in life may boost brainpower. In fact, studies show that infants given omega-3-supplemented formula during their first 4 months were better at solving “baby problems” (for example, finding a hidden toy) than infants on a standard formula. It’s not yet clear that this translates to smarter kids and adults, but in the meantime, you still might want to look out for omega-3-supplemented formula in stores.