Nutritionists call omega-3 and omega-6 fatty acids “essential” fats for good reason. The human body needs them for many functions, from building healthy cells to maintaining brain and nerve function. Our bodies can’t produce them. The only source is food.
These polyunsaturated fats are important for another reason. There’s growing evidence that they help lower the risk of heart disease. Some studies suggest these fats may also protect against type 2 diabetes, Alzheimer’s disease, and age-related brain decline.
Omega-6 mostly comes as linoleic acid from plant oils such as corn oil, soybean oil, and sunflower oil, as well as from nuts and seeds. The American Heart Association recommends that at least 5% to 10% of food calories come from omega-6 fatty acids.
Omega-3s come primarily from fatty fish such as salmon, mackerel, and tuna, as well as from walnuts and flaxseed in lesser amounts.
Scientists are still debating the optimal amount of fat in a healthy diet, as well as the best proportion of omega-6s and omega-3s. For now, there are several simple changes most of us could make to take advantage of their substantial health benefits.
1. Switch from Butter and Cream to Unsaturated Oils
Saturated fats, which come mostly from animal sources, raise LDL, the form of cholesterol that clogs arteries. Unsaturated fats from vegetable oils, nuts, and fish can help lower cholesterol levels.
“Replacing saturated fats with unsaturated fats is still one of the healthiest changes most Americans can make,” says Jeannie Gazzaniga-Moloo, PhD, RD, a spokeswoman for the American Dietetic Association.”
Examples of simple ways to make the switch include:
- Sautéing in canola or other vegetable oil instead of butter
- Drizzling olive oil or another flavorful oil over vegetables
- Dipping bread in olive oil instead of spreading it with butter
- Using non-hydrogenated margarine in place of butter
- Making cream sauces with low-fat yogurt
- Favoring oil-based salad dressings over creamy dressings
2. Add Nuts to the Menu
Nuts abound in omega-3s and omega-6s, which may explain why they have been shown to help protect against heart disease. In a 2010 analysis of four studies, researchers found that a weekly serving of nuts lowered the risk of dying of coronary heart disease by an impressive 8.3%.
Nuts make a satisfying and convenient snack, of course, but they’re also a great addition to meals.
- Stir-fries with cashews or almonds
- Salads topped with walnuts
- Pesto sauce made with ground walnuts
- Baked chicken or trout with toasted almonds
3. Go Fish for Health
Fish is rich in two forms of omega-3 fatty acids, called eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Growing evidence shows that these two forms are particularly important for lowering inflammation and protecting against heart disease. Indeed, some researchers now think that omega-3 levels, measured in the blood, may be a useful predictor of heart disease risk.
The American Heart Association recommends that people without documented coronary heart disease eat at least two servings per week of a variety of fish (one serving is 3.5 ounces of cooked fish). People with coronary heart disease should eat more, about one gram of EPA and DHA a day, preferably from fatty fish, according to the AHA.
4. Tap Other Sources of Omega-3s
Don’t eat fish? You can turn to other sources of omega-3s. Flaxseed oil, for example, contains about 55% omega-3 fats. Canola oil has about 10%. Soybean oil is about 7% omega-3 fats. Walnuts and leafy green vegetables are also good sources of omega-3s.
All of these foods are healthy choices, experts say. But there’s still some debate about whether they have all the benefits of fish oil. The reason: the omega-3s in flax, canola, walnuts, and other vegetable sources are in the form of alpha linoleic acid, or ALA. Although the body can convert some ALA to EPA and DHA, the two forms of omega-3 fats with proven heart protection benefits, it’s not clear how much is converted.
If you don’t eat fish at all, you may want to talk to your health care provider about taking a supplement that contains EPA and DHA.
The Debate Over Omega-6 vs Omega-3 Fatty Acids
Some researchers are convinced that the healthiest fats are omega-3s, found principally in fish. They insist that omega-6s compete with omega-3s in the body, so the ratio of these two forms of polyunsaturated fats is very important.
“The ideal ratio is one to one or two to one, omega-6 to omega-3,” says Artemis Simopolous, MD, who directs the Center for Genetics, Nutrition and Health, in Washington, D.C., and is widely regarded as an expert in fatty acids. “Unfortunately, the American diet has been flooded with omega-6 fatty acids, mostly in the form of vegetable oils such as corn oil and safflower oil.”
Simopolous says that most Americans would do well to cut back on oils high in omega-6s in favor of oils with more omega-3s, such as canola oil and flaxseed oil.
Not everyone agrees. In 2009, the American Heart Association issued a scientific advisory insisting that omega-6s have important health benefits. “The ratio of omega-6s to omega-3s doesn’t matter since both are good,” says Harvard University School of Public Health cardiologist Frank Sacks, MD, who led the AHA’s advisory board. “The ratio is meaningless because it’s good divided by good.”
The debate isn’t over. Last year, researchers from the National Institutes of Health published an analysis of studies going back more than 40 years. They found that omega-3 was linked to most of the heart disease protection seen in the research. They also found evidence that a diet high in omega-6s may actually increase cardiovascular risk.
For now, experts on both sides of the issue agree that eating sources of omega-3 fats, mostly fish, is important. “Americans already get plenty of omega-6s in their diets,” says Gazzaniga-Moloo. “But many people aren’t getting recommended levels of omega-3s.” The current recommendation calls for two servings of a fatty fish such as salmon a week.
http://www.webmd.com/diet/healthy-kitchen-11/omega-fatty-acids?page=1
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