Omega-3s gain medical ground as Prozac and Celebrex fall from grace
by Craig Weatherby
Last fall, one “superstar” drug after another fell from its pedestal, the victims of exaggerated claims and unforeseen side effects.
Vioxx was the first to fall, followed quickly by Celebrex. New information showed that each of these “COX-2” anti-inflammatory pain relievers appear to pose greater health risks than the far cheaper generic pain relievers—aspirin, ibuprofen, etc.—they were supposed to improve on. Even the primary reason for their introduction—reduced risk of gastric bleeding in comparison with aspirin and ibuprofen—has since proven false.
Omega-3s discourage depression
Now, the ubiquitous anti-depressant drug Prozac has taken an image hit. First came evidence that Prozac may cause violent and suicidal behavior. In October of 2004, the FDA ordered drug companies to place "black box" warnings on the labels of the most widely prescribed class of antidepressants—serotonin reuptake inhibitors or SRRIs—including Prozac, stating that antidepressants increase the risk of "suicidal thinking and behavior in children and adolescents."
Then, an article in the January 1 issue of the British Medical Journal (BMJ) alleged that Prozac patent holder Eli Lilly & Company had long concealed evidence of this problem. British medical regulators were especially upset over the alleged concealment by Lilly, since they had recommended that many antidepressants not be prescribed for children and teenagers, but had not included Prozac in those advisories.
According to news reports, some of the documents cited by the BMJ article date back to the 1980's and include memos between Eli Lilly employees that show a link between Prozac and violent or suicidal behavior among people taking the drug.
DHA considered vital to mood control
The omega-3 fatty acid known as DHA is a major component of cell membranes in the brain, and dietary DHA has been found to improve the symptoms of bipolar disorder, schizophrenia, and depression. A growing body of evidence indicates that omega-3 fatty acids—especially DHA—offer a promising dietary defense against depression (DHA is found only in seafood, and is concentrated in fatty, cold water fish like salmon, sablefish, and tuna).
Research over the past few years yielded these highly suggestive findings:
- People suffering from major depression generally have lower-than-average body levels of omega-3s (especially DHA).
- Omega-3s alleviate major depression, according to the results of the first placebo-controlled clinical trial, published in 2003. As the authors concluded, “From the preliminary findings in this study, omega-3 PUFAs could improve the short-term course of illness and were well tolerated in patients with major depressive disorder.”
- People in geographic areas where consumption of DHA is high enjoy decreased rates of depression, according to most studies (A recent population study in Finland found no connection).
- People who typically have below-average tissue levels of DHA—such as alcoholics, and women in the postpartum period—suffer higher than average rates of depression.
This is not to say that people diagnosed with depression can safely toss their prescriptions in favor of eating lots of fish: researchers say that controlled clinical trials comparing DHA against standard antidepressants are required before doctors can prescribe DHA as an effective and safe alternative therapy for depression and related mood disorders, such as anxiety.
That said, increased DHA intake is certainly a safe preventive measure. As researchers at Harvard Medical School noted in a year 2000 review article, “Considering that natural medications generally seem best for treating mild to moderate illness, the role of DHA as a therapy for minor and subsyndromal depression also should be considered.”
Omega-3s seen as anti-arthritis ally
Osteoarthritis affects an estimated 21 million Americans, most of them over the age of 45. This most common type of arthritis is caused by gradual degradation of the cartilage in people's knees, hips, backs, and ankle joints. Loss of cartilage results in two sources of pain: 1) rubbing of bone against bone, and 2) indirect pain from the inflammatory response the body mounts in response to injury of tissues surrounding the joint (Cartilage itself has no nerve endings).
While their modes of action remain a bit of a mystery, aspirin and ibuprofen (Advil), naproxen (Aleve), Vioxx and Celebrex provide effective relief from osteoarthritis pain, primarily through their anti-inflammatory actions (Vioxx was withdrawn from sale last fall following reports of its risks to heart health).
Omega-3s also dampen inflammation, but not strongly enough to provide the kind of pain relief people get from taking pharmaceutical drugs.
However, dietary omega-3s exert physiological effects that can help slow the progress of osteoarthritis, and limit related pain and immobility. Test tube studies involving cartilage cells (chondrocytes) show that omega-3s decrease the cartilage degradation and inflammation associated with osteoarthritis. As the authors of one study put it, “…our data provide evidence supporting dietary supplementation of n-3 PUFA [omega-3s], which in turn may have a beneficial effect of slowing and reducing inflammation in the pathogenesis of degenerative joint diseases in man.”
What about the far less common, far more debilitating disease known as rheumatoid arthritis (RA)? This highly painful condition is caused by a mysterious malfunction of the immune system that causes the body to mount an inflammatory attack its own joint tissues. Since omega-3s are anti-inflammatory, it's no surprise that most clinical studies show that people with rheumatoid arthritis report substantial relief from dietary omega-3s.
Yet, for a purely non-medical reason, omega-3s remain an under-prescribed therapy for either form of arthritis. As the authors of a recent research paper explained, “Since fish oils do not provide industry with the opportunities for substantial profit associated with patented prescription items, they have not received the marketing inputs that underpin the adoption of usual pharmacotherapies.” In other words, drug companies can't make money selling natural products like omega-3s, because they cannot be patented and, compared with novel drugs, offer little profit potential.
Last, but not least, one huge advantage of fish oil over nearly every pharmacological solution is its safety. Only a fishy aftertaste (“repeat”) occurs with some brands, which is completely harmless and usually passes quickly—a very small price to pay for fish oil's manifold, well-proven benefits.
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