While it's important to identify better screening techniques for people suffering from untreated depression, it'd be ideal to find deeper answers about where mood disorders originate, and why they seem to be growing.
Capt. Joseph Hibbeln, M.D., has taken on that challenge. Though he's acting Chief for the Section of Nutritional Neurosciences at the National Institute on Alcohol Abuse and Alcoholism, Hibbeln is best-known for his 17 (and ongoing) years of research with the National Institutes of Health regarding the role of omega-3 deficiencies in violence, aggression and suicide.
In short, he believes that mental illness could very well come from us eating too little fish.
Oil and trouble
As Hibbeln explains, we now get up to 10 percent of all of our calories from soybean and seed oils, which contain large amounts of omega-6 fatty acids.
"And omega-6 fatty acids compete with the omega-3 fatty acids for space in the brain and space in the rest of the body," Hibbeln says.
Hibbeln says there are several things that happen to the human brain when it's short on omega-3 fatty acids, and much depends on when in the lifescale the deficiency occurs. One set of his published data from 2007, via a longitudinal study by Britain's University of Bristol that enrolled 11,000 pregnancies in the early 1990s, showed that when women follow the 2004 advice of the U.S. Environmental Protection Agency and the Food and Drug Administration to avoid fish in pregnancy, it nearly doubles the risk that their children will have a low IQ at age 8. Hibbeln believes that this is largely due to a deficiency of omega-3s in pregnancy having a residual effect on the child's IQ.
His team also published evidence, in the same paper, that those same children had more abnormalities in positive social functioning and increased problems with peer interactions. And while it didn't look closely at depression and suicide in the children (who are now 18 years old), the team did find that the mothers became very depressed in pregnancy if they did not eat sufficient amounts of fish.
"What we believe is going on," Hibbeln says, "is that the omega-3s are so important for the baby's brain and developing nervous system, that the mothers we know transport their own omega-3s across the baby's placenta. If mothers don't eat fish, their gas tank gets empty.
"Lack of fish consumption approximately doubled the risk of depression and suicidal thinking in the mothers, [from] about 4 percent to 9 percent of the population. That's pretty frightening, about 9 percent of the population thinking about suicide in the third trimester."
Hibbeln notes that part of the problem is that omega-3s are not produced by the human body; they have to be consumed. Supplements are good, though Hibbeln notes that consuming fish will also provide important protein and micronutrients. (Though omega-3s can be found in certain seeds and nuts, studies show those omega-3s don't work the same in promoting mental and physical health.)
A body of data
So what, exactly, does this all mean when it comes to our kids?
Hibbeln knows exactly what he would tell parents: "You wouldn't willingly let your child become deficient in iodine and get hypothyroidism. You wouldn't willingly become deficient in folate during pregnancy. We have an accumulating body of data — and by that I mean 8,000 clinical trials of omega-3 fatty acids in human conditions, and 83,000 studies of omega-3 fatty acids in the basic chemistry side. And that number of studies has been doubling every four years.
"We know that omega-3 fatty acids will markedly reduce the risk of cardiovascular disease, and in my experience, in 17 years in this field, the effects of preventing and treating psychiatric disorders, especially depression, seems to be even larger than the effects on cardiovascular disease."
Hibbeln says research shows that omega-3 fatty acids work as antidepressants — in fact, their efficacy is "as good or better" than classical antidepressants. ("Which is pretty cool, I think," he adds.) And they often work in treatment-resistant depression where other antidepressants have failed.
There are critics who challenge Hibbeln's studies, but for him, it comes down to one thing.
"There is no harm in ensuring intakes of 500 milligrams a day to 1000 milligrams a day of omega-3s for your children. There's no harm. The FDA says that this is generally regarded as safe." He pauses before continuing. "I think there is abundant harm in deficiency."