Fish oil is among the most popular natural products used by American adults with nearly 19 million turning to fish oil, omega-3 or fatty acid supplements to combat heart disease, rheumatoid arthritis, dry eye symptoms and mental health effects, reports the National Center for Complementary and Integrative Health. However, the evidence of its effectiveness is largely inconclusive. Consuming omega-3 fats has long been touted as protection against — and in some cases reversal of — a number of conditions, including anxiety and depression, according to Medical Express.
But a systematic review of dozens of trial experiments found suggests the opposite. To come to their conclusions, researchers at the University of East Anglia in England analyzed 31 trials of adults both with and without depression and anxiety. More than 41,000 study participants were randomized to either consume more fish oils or maintain their usual intake for at least six months.
"Our previous research has shown that long-chain omega-3 supplements, including fish oils, do not protect against conditions such as heart disease, stroke, diabetes or death," said lead study author Lee Hooper. "This large systematic review included information from many thousands of people over long periods. Despite all this information, we don't see protective effects.
Hopper added that the most trustworthy "studies consistently showed little or no effect of long-chain omega-3 fats on depression or anxiety" and that such supplements should not be encouraged as treatment.
That's not to say that there are no health benefits to consuming fish oils. Study co-author Katherine Dean says that oily fish can be a "very nutritious" food when consumed as part of a balanced diet. Omega-3 is a type of fat and small amounts are necessary for health, notes Technology Networks. A recent report investigated by The New York Times found that fish oil supplements may have benefits in at-risk and subset populations, but may be moot in otherwise healthy groups.
"We found that there is no demonstrable value in people taking omega-3 oil supplements for the prevention or treatment of depression and anxiety," said Dean. "Considering the environmental concerns about industrial fishing and the impact it is having on fish stocks and plastic pollution in the oceans, it seems unhelpful to continue to swallow fish oil tablets that give no benefit."
In June, the U.S. Food and Drug Administration announced that it did "not intend to object to the use of certain qualified health claims stating that consuming ... omega-3 fatty acids in food or dietary supplements may reduce the risk of hypertension and coronary heart disease," leaving the supplements largely unregulated at a federal level.