HEALTH FROM THE DEEP
Reduce the risk of heart disease
Prevent breast and colon cancers
Promote larger birthweight babies
Reduce inflammation
For years, Americans have wisely been reducing the amount of fat in their diets. But there’s one fat you may want to get more of instead of less: the fat in fish. When it comes to healthy eating, fish swims to first place.
Cold-water fish contain a number of polyunsaturated fats, which are known collectively as omega-3 fatty acids. Omega-3s benefit the fish by helping them stay warm in chilly waters. In people, the same fats go a long way toward promoting better health.
Consider Greenland’s Eskimos. They eat fish to their hearts’ content, which may be why they have very low levels of heart disease. Similar benefits have been observed in fish eaters around the world. People are simply a lot less likely to die from heart disease when fish plays a role in their diets. There is compelling research that the oils in fish may do far more than protect the heart, however.
Perhaps most significant, a team of scientists at the Harvard School of Public Health reported that overall mortality was 17 percent lower among people who ate fish twice a week compared with people who ate little or no seafood.
A big reason for these protective effects is omega-3s’ ability to reduce inflammation. “As we eat more processed foods, such as cookies, crackers, and fast food, we get a lot of omega-6 fatty acids,” says Gretchen Vannice, MS, RD, research coordinator at Nordic Naturals, who has studied omega-3 fatty acids extensively. “Omega-6 fatty acids increase inflammation. And omega-3 fatty acids decrease inflammation, so if we don’t get enough omega-3s to counteract the omega-6s, we’re in a constant state of inflammation. And inflammation puts us at risk for a whole host of conditions, including heart disease, overweight, and even depression,” she says. “We should get a ratio of 4:1 omega-6s to omega-3 fatty acids, but most people get an estimated 15 to 20:1, so we’re way undernourished with omega-3s.”
In the 1980s, a round of studies reported that a diet high in fish could help protect against heart disease, prompting many Americans to trade some of their red meat and poultry for a couple of fish meals each week. They made the right choice.
Research has shown that people who eat fish are less likely to die from heart disease than their non-fish-eating counterparts. A recent study done at the Harvard School of Public Health reported that the death rate from heart disease was 36 percent lower among people who ate fish twice a week compared with people who ate little or no seafood.
In a study done at King’s College in London, participants ages 45 to 70 increased their omega-3 intake by eating fish until their ratio of omega-6s to omega-3s was 3:1. As a result, their triglycerides went down, lowering their risk of heart disease.
The omega-3s in fish appear to work by putting the brakes on the body’s production of inflammatory prostaglandins, leukotrienes, and thromboxane, naturally occurring compounds that, in large amounts, may cause blood vessels to constrict, elevating blood pressure. These compounds also may promote unwanted clotting in the bloodstream, which can lead to heart disease.
“The top salmon you can buy is the Alaskan salmon from the Yukon River, the longest river in the Bering Sea,” says Jana Klauer, MD, a New York City–based physician who specializes in the biology of fat reduction. “The king salmon are so big and fatty, they’re chock full of omega-3 fats. It is really a spectacular fish to consume,” she says. “They are in season in May and flown out on ice. You can find them at many of the larger natural foods stores and supermarkets. A bonus for eating Alaskan salmon: By buying them, you are supporting a local economy—the native fishermen,” she adds.
The ability of omega-3s to prevent clotting is particularly important, says James Kenney, PhD, RD, director of nutrition research and educator at the Pritikin Longevity Center and Spa in Aventura, Florida. Clots that form in the bloodstream can block the flow of blood to the heart or brain, possibly causing heart attacks or strokes. Further, the oil found in fish appears to raise levels of high-density lipoprotein cholesterol, the good cholesterol that helps keep fatty sludge from depositing in the arteries.
Research shows that fish can offer particular benefits to people who have already had one heart attack. Having two fish meals (up to a total of 12 ounces of fish) a week may reduce the chances of suffering a second, fatal heart attack.
In addition to its favorable effects on clotting and cholesterol, the oil in fish appears to help keep the heart beating in a healthy rhythm. This is important because potentially serious heartbeat irregularities, called arrhythmias, may lead to cardiac arrest, in which the heart stops beating entirely. There is increasing evidence that the omega-3s in fish somehow fortify the heart muscle and keep it beating regularly. In one study, people getting nearly 6 grams of omega-3s a month—the equivalent of having a 3-ounce serving of salmon weekly—had half the risk of cardiac arrest as those who ate no omega-3s.
And the heart-healthy benefits seem to extend beyond adults into kids as well. A report released by the Institute of Medicine in Washington, D.C., showed that the heart benefits of seafood outweigh the risks in infants as well as in adults.
The report showed that omega-3 fatty acids found in fish promote healthy vision and brain development in infants whose mothers consume seafood while they are pregnant or breastfeeding. These healthy fats also appear to lower the risk of delivering a preterm or low-birthweight baby.
As a result of the heart-protective benefits of fish, the American Heart Association recommends that all adults eat fish at least two times a week. However, the AHA also notes that some types of fish may contain high levels of mercury, PCBs (polychlorinated biphenyls), dioxins, and other environmental contaminants. Levels of these substances are generally highest in older, larger, predatory fish and marine mammals. The benefits and risks of eating fish vary depending on a person’s stage of life. Children and pregnant and breastfeeding women should follow FDA guidelines for avoiding mercury-contaminated fish. Fish with potential for the highest mercury contamination are shark, swordfish, king mackerel, and tilefish. Eating a variety of fish will help minimize any potentially adverse effects due to environmental pollutants.
While fresh fish delivers some of the most delicate flavors imaginable, it goes bad in a hurry. One day may be all it takes to turn a beautiful, flavorful fish into a dish you’d rather forget. To get the best taste from fish every time, here’s what you can do:
Follow your nose. Fresh fish should smell just slightly briny. Off odors develop in the gut cavity first. When buying fish, always take a sniff in the belly area to make sure the fish is clean and fresh.
Incidentally, beware of fish that has been prewrapped in plastic. Unless the fish has been frozen, it can go bad very quickly.
Look at the eyes. When buying whole fish, look at the eyes; if the fish is fresh, they will be clear, bright, and bulging. Eyes that are slightly milky or sunken are an indication of the condition of the fish—that freshness is waning.
Check the gills. The gills should be moist and bright red, almost burgundy. If they are gray or brown, the fish is old, and you should pass it by.
Press the flesh. The flesh on fresh fish should be firm and springy. If you press it with your finger, and the indentation remains, the fish is old and won’t deliver the best flavor.
Nutritionists have long advised us to eat less fat, especially the fats in meats and dairy products, to reduce the risk of certain types of cancer. But the fat in fish is a healthy exception. “There’s excellent evidence that eating fish provides protection against breast and colorectal cancers,” says Bandaru S. Reddy, PhD, professor of research in the department of chemical biology at Rutgers University in New Brunswick, New Jersey.
Fish protects against cancer in much the same way that it helps prevent heart disease—by reducing the body’s production of prostaglandins. In large amounts, prostaglandins act as tumor promoters—that is, they encourage cancer tumors to grow, says Dr. Reddy.
In a study of people in 24 European countries, British researchers found that people who regularly included fish in their diets were much less likely to get cancer. Indeed, they estimated that having small servings of fish three times a week, in addition to decreasing intake of animal fats, would reduce the death rate from colon cancer in men by nearly one-third.
You wouldn’t think that eating fish could improve breathing difficulties caused by smoking, but that’s exactly what researchers have found. Consumption of fish has been linked with better lung function in adults.
There’s only so much that the occasional tuna steak can do to protect you from developing lung disease if you smoke. But if you’re trying to quit or if you live with someone who smokes, eating fish is one way to reduce the damage. “If you smoke, you are under big-time oxidative stress, which will increase inflammation,” says Vannice. “Omega-3 fatty acids in fish help protect cell walls, which will reduce the oxidative stress. Plus, omega-3s will help your nerves and therefore lower your anxiety level—a big thing for people who are trying to quit,” she says.
Here are two additional reasons to get more fish in your diet. In one study, researchers looked at the fish-eating habits of more than 8,700 expectant moms in Denmark. They found that the more fish the women ate, the less likely they were to deliver preterm, and the less likely they were to have a baby with a low birthweight. This is important because larger babies are usually healthier than those who are underweight.
Researchers speculate that the omega-3s in fish prevent preterm delivery by helping to promote bloodflow through the placenta, allowing the fetus to get more nutrients. In addition, by blocking the effects of prostaglandins, which are responsible for initiating uterine contractions, omega-3s might help prevent early labors and deliveries.
The omega-3 fatty acids in fish also help protect against autoimmune diseases, such as rheumatoid arthritis, and help prevent dementia and Alzheimer’s disease, says Vannice. In addition, two studies have shown that taking fish oil in addition to exercising for 45 minutes, three times a week, leads to a lower percentage body fat, suggesting that fish oil may also aid in weight loss.
Shop for salmon. All fish provide some omega-3s, but salmon is perhaps the best choice, with a 3-ounce serving of Chinook (king) salmon providing 3 grams.
Don’t fish for farm-raised varieties. “Farm-raised fish are often fed grains instead of their natural diets, which affects the fat in their bodies—when they are fed omega-6 fats in the grains, they become sources of omega-6 fats,” says Jana Klauer, MD, a New York City–based physician, who specializes in the biology of fat reduction and is the author of How the Rich Stay Thin.
Look for deep colors. The more deeply colored the salmon, the more omega-3s it provides. As a rule of thumb, the more expensive varieties of salmon generally have the most omega-3s.
Shop for variety. It’s not only salmon that has omega-3s. Other good sources include Spanish mackerel, tuna, sardines, anchovies, whitefish (fresh, not smoked), and herring.
Enjoy it canned. One of the easiest ways to get more omega-3s into your diet is to pick up a can of water-packed chunk light tuna (avoid albacore, which has been linked to mercury). If you’re making tuna salad, choose a low-fat or fat-free mayonnaise, or skip the mayo altogether and use a mustard instead. The unhealthy fats in regular full-fat mayonnaise will more than offset the benefits of the healthy fats in the fish.
Use your microwave. The high cooking temperatures used in conventional cooking methods such as broiling can destroy nearly half the omega-3s in fish. Microwaving has little effect on these beneficial oils, however, so it’s a good cooking choice for getting the most benefits from your fish.
Rinse the salmon with cold water. Pat dry with paper towels.
Trim both the tough green part and the root end from the leek and discard them. Cut the leek in half lengthwise. Rinse thoroughly with cold water, pulling apart the layers to remove all the grit.
Cut the leek into very thin slices. Spread two-thirds of the slices evenly over a large microwaveable plate. Cover loosely with waxed paper, and microwave on high for 30 seconds.
In a small bowl, combine the ginger, sherry, soy sauce, and the remaining leek slices.
Place the salmon on the plate over the microwaved leek slices, skin side down and with the pieces arranged in spoke-fashion so the thickest parts face outward. Pour the ginger mixture evenly over the top. Cover loosely with waxed paper.
Microwave on high for 4 to 6 minutes, or until the salmon is opaque in the center. Test for doneness by inserting the tip of a sharp knife in the center of 1 fillet.
Let stand for 5 minutes before serving.
Makes 4 servings
Calories: 229
Total fat: 11.9 g
Saturated fat: 2.9 g
Cholesterol: 75 mg
Sodium: 232 mg
Dietary fiber: 0.9 g
Place the lavash on a cutting board.
In a small bowl, combine the tuna, vegetable dip, and olives. Spoon the tuna mixture down the middle of each lavash.
Cover the tuna mixture with the sliced carrots, then cover the carrots with the salad greens.
Tuck in one or both ends of each lavash, and roll up tightly. Slice each crosswise in half.
Makes 2 servings
Cook’s Notes: You can easily double or triple this recipe for a crowd. Use leftover dip with leftover baby carrots for healthy snacks.
Calories: 277
Total fat: 5.5 g
Saturated fat: 0.5 g
Cholesterol: 53 mg
Sodium: 794 mg
Dietary fiber: 4 g