Scientists are shouting at us from their science journals, albeit in their sometimes inscrutable scientific language.
Listen up: By what we eat, we are starving our cells of omega-3 fatty acids and drowning them in omega-6.
Omega-3 is the "essential fatty acid" found in fish and other foods that many people recognize as good for heart health. In fact, most people taking fish oil capsules are doing so because they're concerned about their cardiovascular systems.
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A few years ago researchers surmised that omega-3 might be much, much more than a heart thing. Now study after study is showing that this is almost certainly true:
Righting our omega-3/omega-6 imbalance -- by getting more omega-3 in our diets -- not only will make our hearts healthier but very likely our brains, eyes and joints, to name a few body parts, plus reduce inflammation in our bodies and even improve mood.
A study reported in the April issue of Psychosomatic Medicine looked at adults with symptoms of stress and depression. Those low on omega-3 compared with omega-6 had much higher cytokine levels, markers of inflammation, in their blood.
"And inflammation is behind a whole laundry list of diseases," said Janice Kiecolt-Glaser, psychiatry professor at Ohio State University and lead author of the study. She noted that these results and many others are showing omega-3 to have anti-inflammatory effects, omega-6 to be pro-inflammatory.
Late last year Tufts University reported that study participants with the highest levels of omega-3 had a 47 percent reduced risk of dementia. A month earlier Swedish scientists reported that omega-3 appeared to slow the decline of people with mild Alzheimer's disease.
"This is the area where we're getting the most exciting information," said William Harris, formerly a heart researcher at St. Luke's Hospital. Last year he became director of the Nutrition and Metabolic Disease Research Institute at the University of South Dakota. "This has shown up now in three different studies, that people who eat more fish or have high blood levels of omega-3 seem to be at lower risk for senile dementia."
Our bodies require "essential fatty acids" called omega-6 and omega-3. We need both, but we can't manufacture them so we must get them from food. Many vegetable oils are rich in omega-6, and that means most of us get a lot of it in our diets.
Estimates vary, but many experts agree that the balance of omega-6 to omega-3 in the diet should be lower than 4-to-1. Americans typically are way out of whack, closer to 20-to-1.
"It's really one of the most common problems that modern Americans have," said James O'Keefe, cardiologist at St. Luke's Hospital in Kansas City. His book, "The Forever Young Diet & Lifestyle," co-authored with his wife, Joan O'Keefe, devotes a chapter to omega-3. More than 90 percent of Americans have a "sub-optimal" balance of omega-3 to omega-6, he said.
Talk of "imbalance," Harris said, should not confuse the issue, which for most people is to concentrate on getting more omega-3 from fish and fish oil. That's what the science is proving successful, he said.
Here's an example of omega-3's importance:
Each of the body's 100 trillion or so cells is enveloped in a membrane, which is the mechanism for communication within the body, O'Keefe said, ushering in the right chemicals and keeping out the wrong ones. The cells use essential fatty acids to do this work.
Many of the cells, especially in the heart and brain, prefer omega-3 fatty acids, referred to as DHA and EPA. But they'll use what's available, grabbing omega-6 or unhealthy saturated fats and trans fats. But omega-6 can make the membranes rigid and dysfunctional, he said.
O'Keefe is a heart guy, but he's impressed with the recent proliferation of studies about omega-3 and its effects on other body functions. For instance, he said, research is showing that a proper level of omega-3 improves brain development in third-trimester fetuses and in newborns.
Other studies are showing its effect on reducing stress. Promising studies link the positive effects of omega-3 on bone density, diabetes, macular degeneration and obesity. And, of course, the evidence continues about omega-3 and heart health, a link that's been known for years.
A new study in The Lancet followed more than 18,000 patients in Japan who were taking cholesterol-lowering statin drugs. Those who also were given omega-3 supplements were 19 percent less likely to have a "major coronary event."
Most experts blame the evolution of our food supply for the lack of omega-3 in our diets. Our ancient ancestors ate more foods rich in omega-3, including fish, nuts and green leafy vegetables. Early humans may have had an omega-6/omega-3 balance of 1-to-1.
A more modern factor, said Martha Belury, associate professor of nutrition at Ohio State, is that food manufacturers moved toward polyunsaturated fats, such as corn oil, and away from harmful saturated fats. That was a good thing. But because we eat so much processed food, our diets became flooded with omega-6.
"We shifted away from omega-3 because of what was available easily in our market and what was cheap," Belury said.
Now, some food makers are adding omega-3 to products such as eggs and vegetable oils. And plenty of tasty foods are good sources of omega-3, including cold-water fish, walnuts and flax seed, she said.
"But people do have to think actively about consuming these foods," she said.
However, said Harris, omega-3 from plant sources is different from the omega-3 in fish and fish oil. Only small amounts of it are converted in our bodies into the types of omega-3 scientists have found to be most beneficial.
Harris said that as people grow increasingly more aware of the health effects of the omega-3/omega-6 imbalance, food manufacturers will begin fortifying more and more products with omega-3.
"There will be a lot of that coming," he said, "but I think that's a few years away."
Given how we eat, O'Keefe's advice is that many adults need to regularly take two supplements, a standard multivitamin and fish oil.
"It's a fundamental component of good health," he said.
Do you know your omega-3 score?
If you want to know how out of balance you are, in terms of omega-3 and omega-6, that is, a Kansas City, Mo., company can tell you.
For $95, OmegaMetrix will determine your omega profile and provide dietary suggestions for a healthier balance. The company sends a blood collection kit by mail. Collection can be by finger stick or by having blood drawn at a clinic or doctor's office.
Customers in Missouri and Kansas don't need a doctor's order to get the test. Insurance generally doesn't cover the cost, said general manager Ron Bremer, but medical savings accounts can be used.
For information and to order a collection kit, go to omegametrix.com or call (816) 931-0797 or (866) 677-4900.
FISH AND FISH OIL SUPPLEMENTS
Fish such as salmon, albacore tuna, lake trout and sardines are high in omega-3 fatty acids, particularly the types referred to as EPA and DHA.
The American Heart Association says 1 gram of EPA+DHA provides protection for the heart. The Food and Drug Administration says up to 3 grams a day of EPA+DHA are generally safe.
A 3-ounce serving of salmon or a 4-ounce serving of albacore white tuna is roughly equivalent to 1 gram of EPA+DHA.
Mercury levels in fish are a concern. The FDA says most people can safely eat 14 ounces of fish a week. Eating different kinds of fish is a good idea. Guidelines are stricter for pregnant women, nursing women and children.
Fish oil capsules are often recommended as a way to increase intake of EPA and DHA. Standard capsules contain 300 mg of EPA+DHA, so it would take three capsules a day to get close to 1 gram.
Some people experience "fishy burps" with fish oil capsules. Some find relief by taking enteric-coated capsules or by taking them with meals or at bedtime.
Ask your doctor before taking supplements or changing your diet. Excessive bleeding is a concern about fish oil supplements for some people.
Other foods naturally contain omega-3 fatty acids, a type referred to as ALA. The body converts ALA to beneficial EPA and DHA but in modest amounts. While getting omega-3 benefits from plant foods is less of a sure thing than with fish or fish oil, it couldn't hurt. Vegetarians who avoid fish would do well to focus on some of these foods. Another option is to buy foods such as eggs, peanut butter and oils that have been fortified with omega-3.