Why the secret to longevity might be found in pickled herring
Excerpted from Prevention's Brainpower Game Plan book by Cynthia R. Green, Ph.D., and the Editors of Prevention
At age 115, Henrikje van Andel-Schipper was the oldest person in the world at
the time of her death in 2005. Scientists who interviewed the Dutch woman say she remained sharp-witted and just plain witty until her last days. Her secret? When asked, van Andel-Schipper quipped, “Pickled herring.” Then again, maybe she wasn’t joking. Eating plenty of fish and shellfish can help keep your mind in top form and lower your risk of dementia, multiple studies suggest.
What’s so magical about seafood? Most scientists believe it’s the dose of omega-3 fatty acids you get with every bite of tuna or trout. Omega-3 fatty acids are powerful and versatile nutrients. Your body needs fatty acids of all different types, from various foods. One of the most important jobs for fatty acids is forming cell membranes. About 40 percent of the fatty acids in brain cell membranes are docosahexaenoic acid, or DHA, which is one of the main omega-3 fatty acids in fish oil. Experts believe that DHA is probably necessary for transmitting signals between brain cells. Another omega-3, known as eicosapentaenoic acid, or EPA, appears to be important for brain health, too.
Better performance and long-term brain health
Some research hints that enjoying regular servings of broiled salmon or baked haddock may make your brain work more efficiently. In a 2007 study, researchers at Wageningen University in the Netherlands analyzed blood samples from 807 men and women over 50 and found that those with the highest levels of omega-3 fatty acids scored 60 percent to 70 percent better on tests that measured reaction time and speed of processing complex information than people who had low omega-3 levels. Other research suggests that eating fish helps bolster your defense shield against dementia. In a 2006 study involving 899 men and women, researchers at Tufts University found that people who ate fish three times a week and had the highest levels of DHA in their blood slashed their risk of Alzheimer’s disease by 39 percent and other forms
of dementia by 47 percent.
Fish has another important benefit for the brain: it helps prevent strokes. In a 2002 study in the Journal of the American Medical Association (JAMA), researchers studied more than 43,000 men and found that those who ate fish one to three times per month were about half as likely to suffer these potentially devastating “brain attacks” as those who rarely ate fish. Massive strokes can be fatal or leave victims paralyzed or plagued by other severe side effects. However, even “silent strokes”—which may occur unnoticed, without producing obvious symptoms—can cause cognitive problems, including memory loss. As many as one in 10 middle-aged adults has suffered a silent stroke and doesn’t know it.
Studies show that silent strokes more than double the risk of developing dementia. Scientists have made some other discoveries that make the case for eating fish even more compelling. For example, lab rats fed diets rich in omega-3 fatty acids learn more quickly and have better memories than those fed diets high in unhealthy fats and sugar. Studies also show that feeding omega-3s to lab animals increases levels of BDNF, a protein that is needed for the growth and survival of brain cells. Other studies hint that DHA helps brain cells produce energy more efficiently and prevents the formation of cell damage called oxidative stress (which you’ll read more about soon).
Eating seafood regularly will do much more than boost your Brain IQ, of course. After all, studies show that people who eat fish just once a week cut in half the risk of sudden cardiac death, which kills more than 300,000 Americans each year. Eating fish also lowers levels of artery-clogging blood fats called triglycerides and confers a slight drop in blood pressure. Those changes alone could reduce your risk of heart disease and other conditions—including dementia—later in life. As the nutritional benefits of omega-3s have become better known, it’s no wonder that consumption of fish and shellfish has soared 30 percent in the United States over the past generation. However, many people still don’t consume adequate levels of omega-3s. People often ask me if it’s true that fish is “brain food,” like their grandmothers told them. As you can see, the research offers powerful evidence that your grandma was right: eating fish really does seem to be good for the brain. The Brainpower Game Plan gives you plenty of ideas for including this nutritional powerhouse in your weekly meal plan.
Seafood and your mood
Eating fish may be good for your emotional health, too. Several studies have shown that depression rates tend to be low in countries where seafood is a popular menu item. For instance, depression is relatively rare in Iceland, where consumption of seafood is five times higher than in the United States or Canada. Mounting research suggests that fish oil may play a role in combating the blues. For example, University of Pittsburgh researchers showed in a 2007 study that people with the highest blood levels of omega-3 fatty acids were significantly less likely than people with low levels to say they felt mildly or moderately depressed.
Fish benefits for fish haters
Some people who don’t like fish but want to enjoy the brain boost and other health benefits of fish oil turn to other food sources of omega-3 fatty acids, which include flaxseed, walnuts, canola oil, and soybeans. Or they shop for “functional” foods, such as eggs, mayonnaise, breakfast cereal, and others that contain added omega-3 fatty acids. Sounds like a great alternative, but unfortunately, most of those foods do not contain the same omega-3s you get from fish oil, which are known as DHA and EPA. Some of the eggs, mayo, and other food products at your local grocer that are enriched with omega-3s contain a form called alpha-linolenic acid (ALA). That’s the same form found in flaxseed and other non-marine sources.
While nutrition scientists sing the praises of DHA and EPA, far less is known about the health benefits of ALA. Your body does convert ALA to DHA and EPA, but the process is not efficient. Lab studies show that only a small fraction of the ALA you consume ends up as DHA and EPA. (Note to vegetarians: DHA is also found in algae supplements.) Some food products promoted as good sources of omega-3s do contain added DHA and EPA, but usually very little. For instance, according to the Center for Science in the Public Interest (a consumer health watchdog group), a 6-ounce serving of Atlantic salmon has about 100 times more DHA and EPA than a serving of DHA-fortified yogurt or milk. Likewise, one popular brand of yogurt boasts of offering 32 milligrams of DHA per serving. Yet that’s the amount you would get from a small bite of salmon. Including flaxseed, walnuts, canola oil, soybeans, and other sources of ALA in your diet remains a great idea, since they offer other important health benefits. Just keep in mind that eating those foods probably won’t significantly increase your blood levels of DHA and EPA. Eating fish (or taking fish oil supplements) remains the best way to get your dose of omega-3s.
More on Increasing Your Brainpower:
* The Pleasure Principal: Why a Little Indulgence Won’t Hurt Your Health
* Trim Down to Smarten Up
* Best Foods For Focus
* Video: Simple Forgetfulness or Something Serious?
* Purchase the Brainpower Game Plan
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