March 3, 2006 -- Whether you're seriously depressed or simply in a bad mood, eating salmon and other foods high in omega-3 fatty acids just might help you feel better.
Earlier studies appear to link low blood levels of omega-3s to a host of serious psychological conditions, including major depression, bipolar disorder, attention deficit disorder, and even schizophrenia.
Now new research suggests that omega-3s can have a significant impact on everyone's mental health.
"People in our study who had low blood levels of omega-3 fatty acids were more likely to report mild to moderate symptoms of depression, more moodiness, and more impulsivity," says researcher Sarah Conkin, PhD, of the University of Pittsburgh School of Medicine.
Conversely, people with higher blood levels of omega-3s were found to be more agreeable, based on the results of standardized tests.
Conkin presented the findings at the 46th Annual Scientific Meeting of the American Psychosomatic Society in Denver.
Fish and Flaxseed
The American Heart Association recommends eating at least two servings of fatty fish each week, based on strong evidence that the omega-3 fats found in the fish help protect against cardiovascular disease.
The evidence that omega-3 levels also have an impact on mood disorders is less conclusive but growing, says a researcher who conducted some of the first psychological studies examining the fats.
"It is quite clear that omega-3 fatty acids are good for your heart," says psychiatrist Joseph Hibbeln, MD, of the National Institute on Alcohol Abuse and Alcoholism. "But it remains to be seen how good they are for your mind. It is an emerging public health question, but we don't yet know the answer."
Two types of omega-3 fatty acids are found in fatty fish like salmon, sardines, and mackerel -- eicosapentaenoic acid, or EPA, and docosahexaenoic acid, or DHA. A third omega-3, alpha-linolenic acid, or ALA, is found in plant foods such as flaxseed, soybean oil, walnuts, and canola oil.
Impact of Omega-3 Fats
In the new study involving 106 healthy people without major depression or any other diagnosed mood disorder, those who had low blood levels of omega-3 fatty acids scored worse than those with high levels on tests designed to assess mood, personality, and impulsive behavior.
Conklin says low ALA levels were specifically associated with higher levels of impulsivity, which in more extreme forms manifests as attention deficit hyperactivity disorder (ADHD).
"These were normal people who did not have ADHD," she says. "Their impulsivity was not clinically significant, but it was higher than others in the study."
People in the study with low blood levels of EPA and DHA were more likely than others to report experiencing symptoms of mild to moderate depression, Conklin adds.
"Clearly, larger studies are needed to understand the relationship between behavior and these fats," she tells WebMD. "But by following the AHA recommendations to eat two fish meals a week people may be protecting both their hearts and their mental health."
Most People Don't Get Enough
Harvard psychiatry professor Andrew L. Stoll, MD, who wrote the book The Omega-3 Connection, says most Americans find it difficult to get enough omega-3 fatty acids through the foods they eat alone.
He points out that the typical Japanese diet contains as much as 10 times the omega-3 fats as the typical American diet.
He recommends that adults take high-quality fish oil capsules to boost their omega-3 levels, and cut down on their consumption of foods containing omega-6 fats such as foods fried in corn, peanut, and soybean oils.
"It is just hard to get enough omega-3s in this country," he says. "In Japan it is just part of the culture to eat omega-3-rich foods, but that isn't the case here."