Several health organizations have come together to review the evidence.

Here’s what we know.


  • Several studies suggest that omega-3 fatty acids may be beneficial in treating depression.
  • One study found low levels of omega-3 fatty acids in the red blood cell membranes of depressed patients but not in a well-matched healthy control group.

Bipolar disorder or manic-depressive illness

  • One study found that omega-3 was effective when taken with a standard mood-stabilizing drug.
  • Fish oil isn’t a first-line single treatment.


  • Some studies are positive, but a 2006 review concluded, “Overall results are inconsistent.”

Borderline personality disorder

  • A recent study suggests that omega-3 may help treat the symptoms of borderline personality disorder.

Attention deficit hyperactivity disorder (ADHD)

  • After a 30-week study, almost half of the parents reported that their children’s symptoms were improved.

The bottom line?

There’s more work to be done. Until then, here are some guidelines for taking omega-3 supplements.

  • Never use omega-3 fatty acids as a replacement for psychiatric medication unless you have your doctor’s approval.
  • Side effects include indigestion, gas, and fishy-smelling belches.
    • This is less apt to be a problem if you start with a low dose and work your way up.
  • In general, fish oil supplements are safe, but here is a slight possibility of increased bleeding.
  • If you take fish oil supplements, make sure they have been stripped of excess vitamins A and D, which could be toxic if taken in large amounts.
  • If you are pregnant or nursing, avoid shark, swordfish, king mackerel, tuna, and tilefish — they may be contaminated with mercury or other pollutants.
  • Even if you are not pregnant, buy products that were checked for contaminants, like mercury or other heavy metals.

12/12/11 20:56 JR

Hi, I’m JR

John Russo, Jr., PharmD, is president of The MedCom Resource, Inc. Previously, he was senior vice president of medical communications at, a complementary and alternative medicine website.