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Getting hooked on fish can improve your mood

January 18, 2009 2:10 am

EATING FISH two to three times a week may increase your hap-piness and your children's IQ, according to a doctor who has been studying the effects of fish on moods for more than a decade.

Dr. Joseph Hibbeln, who has researched the role of nutrition in mental health for agencies including the National Institutes of Health, said Americans worry too much about contaminated seafood.

These worries, he contends, contributed to eating habits that relegate fish to an occasional meal, when Americans would be better off eating fish several times a week.

I heard Hibbeln, of the U.S. Public Health Service, speak at the American Dietetic Association in Chicago late last year and want to share highlights of his important talk.

Especially now, with the economy in turmoil and many people suffering from seasonal depression, the psychological powers of fish are worth discussing.

FISH BOOSTS MOODS

The omega-3 fats in fish "have more of an effect on depression than most antidepressants," Hibbeln said during his talk in Chicago.

Researchers in one study gave fish oil and dummy pills to people who were so depressed they had already harmed themselves. After 12 weeks, Hibbeln said, the group taking fish oil had a 50 percent drop in depression.

"When DHA [a component of fish oil] was deficient, the foot is on the emotional gas--these people were depressed, anxious and hyperactive," Hibbeln said.

Seafood deficiency may also increase violence. Hibbeln said two studies of prisoners found that giving them a multivitamin and fish-oil supplement reduced repeat convictions.

"We could get a 40 percent reduction in felony-level violence just by adding a multivitamin and omega-3 supplement," Hibbeln said. "In these hard economic times, this could save a lot of money for states."

Hibbeln seems a bit ahead of the psychiatric community--the medical literature supports some positive effects from taking fish oil and calls for more research. Several studies have shown a link between fish oil and reduced depression. And fish oil is also helpful to people suffering from high triglycerides.

But I could not find any group calling for widespread use of fish oil yet.

As a dietitian, I certainly feel hopeful about the effects of omega-3 fats in fish. But when it comes to psychiatric treatment, I would recommend talking about fish oil with your regular doctor as something you might take in addition to other treatment, not as a replacement.

PREGNANT? EAT FISH

At the convention, Hibbeln addressed the issue of whether pregnant women should eat fish, and if so, how much.

"I was distressed by the 2004 [Environmental Protection Agency] advisory, which told women who are fertile and pregnant to avoid eating fish," he said.

He said the recommendation to limit (not totally exclude) fish to 12 ounces per week was set to prevent mercury poisoning and lowered IQs, but did not take into account how omega-3 fats in fish are also necessary to help children's brains develop.

Pregnant women who avoided seafood gave birth to children with double the risk of a low verbal IQ, Hibbeln said. That's compared with women who ate more than 12 ounces of fish a week.

"What was terrifying to me was to see this pattern cross over into other domains," Hibbeln said, mentioning fine motor skills and social development as examples.

Children whose mothers avoid seafood showed delays as late as age 8, Hibbeln said.

Hibbeln criticized U.S. policy in comparison with that in the United Kingdom. "[The U.K.] asks women to eat at least 12 ounces of fish a week, not a minimum. The Brits are a bit ahead of us on this."

As kids get older, Hibbeln said, fish oil can help them if they have attention deficit or reading problems.

"Supplementing omega-3s for three months increased reading age by 9 months and spelling age by 6 months," Hibbeln said.

Other small studies have shown that omega-3s may reduce emotional problems such as conduct disorder, Hibbeln said.

Again, eating fish is not a substitute for medical care.

GETTING ENOUGH FISH

Hibbeln recommended getting about 900 milligrams daily of omega-3 fats found in fish. His estimate is much higher than current government recommendations, which call for 110 to 160 milligrams daily. But he says it's necessary to protect IQ and prevent depression.

"Most of the world's religions, including Christianity, have a dictum to eat fish Wednesday, Friday and holidays," Hibbeln said.

Eating fish two to three times a week would bring the average intake to Hibbeln's goal of 900 to 1,000 milligrams of omega-3s per day.

Higher intakes of omega-3 fats have been linked to lower risk of death, stroke, heart disease, homicide, postpartum depression, major depression and bipolar disorder, Hibbeln said.

Eating a lot of omega-6 fats, found in soybean oil, fried foods and chips, may triple the requirement for omega-3s, Hibbeln said.

So try to avoid those foods, and eat more fish.

Jennifer Motl welcomes reader questions via her Web site, brighteat ing.com, or mailed to Nutrition, The Free Lance-Star, 616 Amelia St., Fredericksburg, Va. 22401.