What to Know About Omega-3s and Fish
Experts explain which fish are best for omega-3s, and which you should limit due to mercury.
The Other Fatty Acid: Omega-6
Unfortunately, the American diet is swimming in omega-6s instead, says Jeffrey Bost, PAC, clinical instructor in the department of neurosurgery at the University of Pittsburgh Medical Center and also co-author of Fish Oil: The Natural Anti-Inflammatory.
"It's in almost everything we eat," he says. "Our diet has shifted away from fresh veggies and fish to foods high in omega-6s, such as crackers, cookies, and corn-fed beef."
Before the introduction of grains, fats, and artificial substances, says Maroon, the ratio of omega-6s to omega-3s was two to one. Today, we consume at least 20 times more omega-6s than omega-3s. The problem is that excessive amounts of omega-6 fatty acids can promote inflammation, a key step in many chronic diseases.
Powerful Health Benefits of Omega-3s
Many studies documenting the benefits of omega-3s have been conducted with supplemental daily dosages between 2 and 5 grams of EPA and DHA, more than you could get in 2 servings of fish a week. But that doesn't mean eating fish is an exercise in futility. Many studies document its benefits. For example, a 2003 National Eye Institute study showed that 60- to 80-year-olds eating fish more than twice a week were half as likely to develop macular degeneration as those who ate no fish at all.
Here's a sample of other recent studies on omega-3s and fish.
Omega-3 Fatty Acids as Brain Food
DHA is one of the most prevalent fatty acids in the brain. This could partly explain why our brains do better with a greater supply. A Rush Institute for Healthy Aging study analyzed fish-eating patterns of more than 800 men and women, ages 65 to 94. Those eating fish at least once a week were much less likely to develop Alzheimer's disease than those who turned up their nose at it.
Another study of more than 2,000 Norwegians, ages 70 to 74, used food-frequency questionnaires to evaluate consumption of five different types of fish. The researchers then conducted cognitive tests. Those who ate fish of any kind were two to three times less likely to perform poorly on the tests.