Fish oil supplements may not prevent mental decline

NEW YORK Wed Jun 13, 2012 9:07am EDT

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NEW YORK (Reuters Health) - Taking daily omega-3 fatty acid supplements doesn't seem to provide any protection against declines in thinking and memory skills in older adults, a new review of medical evidence suggests.

Because the brain is rich in the type of polyunsaturated fatty acids found in fish oil, researchers had figured that adding more of them to a person's diet could boost memory and prevent the changes that lead to cognitive decline and dementia.

But so-called "gold standard" trials of the supplements have been disappointing.

Looking at three such studies lasting between six months and over three years, researchers found there was no difference in changes on learning and memory tests among 4,000 people who took either omega-3 fish oil supplements or sunflower or olive oil as a comparison.

"The evidence suggests, from what is available at the moment, that taking supplements rich in omega-3 fatty acids is not going to benefit cognitive health later in life," said Alan Dangour, a nutrition researcher from the London School of Hygiene & Tropical Medicine, who worked on the new analysis.

The findings, he told Reuters Health, don't rule out a potential benefit on brain health in some people -- and it's still possible long-term use of the supplements may be helpful for preserving thinking and memory skills.

All three studies included in the analysis involved cognitively healthy people over age 60 who were randomly assigned to use supplements or margarine with fish oil or a placebo oil without omega-3 fatty acids.

None of those studies showed a comparative benefit for fish oil on measures of cognition, including word and number learning tests.

"The truth is many people are spending a lot of money on supplements without solid evidence they do something," said Dr. Nikolaos Scarmeas, a neurology and aging researcher at Columbia University Medical Center in New York.

Scarmeas, who wasn't involved in the new study, agreed it may take more than a few years for any benefit of the fatty acids to show up -- if one does exist. Or, it could be that getting extra fish oil through supplements only helps people who are low in the fatty acids to begin with, and not those who get enough through their diet.

But so far, he told Reuters Health, "there's no proof you'll get some benefit from it."

Other studies have suggested fish oil may have beneficial effects on heart health, and recommendations from groups such as the American Heart Association call for people to eat two servings of fish each week, preferably fatty fish such as salmon and tuna.

Neurologist Dr. Gregory Jicha from the University of Kentucky College of Medicine in Lexington said although the presumed benefits of fish oil on cognition aren't clear in randomized studies, people can still reasonably choose to take the supplements because they typically carry few risks.

Stomach problems were the most common side effect among people in the new analysis, and participants on the placebo supplements were just as likely to report mild side effects as those taking fish oil.

Omega-3 fatty acid supplements can be bought over the counter for a couple dollars per month.

Dangour said despite the shaky evidence on the role of fish oil, there are things older adults can do to ward off memory loss.

"Keeping cognitively active in later life and keeping physically active in later life are extremely important for the maintenance of cognitive function," he said.

"Once you retire, it's really important to keep your brain active."

SOURCE: The Cochrane Library, online June 13, 2012.

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Comments (4)
2016935 wrote:
The number 5 cause of death in the USA is not nutrition, its prescription drugs used as directed by your doctor. Where is that story? The big pharma war on nutrition continues as they develope new drugs and put out information campaigns to convince the weak minded sheep in this nation that they need those drugs to survive. Partners in this murder campaign are the AMA, the FDA, and the media along with the bought and paid for members of govenrment thanks to heavy lucrative lobbying. The government does not want 100 year old social security recipients, the government thanks to the raids on social security does not want any one around that does not pay taxes.In short the governement has stolen our future and when you get to 60 or 65 they would prefer you to die.

Jun 13, 2012 10:02am EDT  --  Report as abuse
2016935 wrote:
What does cause mental decline is statin drugs that diminshes the cholesterol levels of the blood not to mention the heart disease those drugs cause. Not one case of heart disease has ever been caused by cholesterol, not one, yet countless numbers of Americans have died from prescription drugs. The USA ranks number at number fifty on longevity yet has the highest health care costs on the planet. Where is that story?

Jun 13, 2012 10:06am EDT  --  Report as abuse
mauiwelch wrote:
A “Good” Cholesterol Fish Story

Fish Oils have received an enormous amount of attention in recent years as a cure-all for a number of chronic diseases; including heart disease, cancer, depression all the way to dementia. As with any supplement that is heavily marketed and associated with large corporations the benefits of taking a fish oil supplement have to be examined.

Fish do not actually produce omega-3 fatty acids, but instead accumulate them by consuming either algae or other fish that have accumulated them. Therefore, large fish like sharks, tuna, salmon may be high in omega-3 fatty acids, but they can also be full of toxic contaminants as well; mercury, dioxin and PCB’s. In March 2010 a lawsuit filed by a California environmental group claimed that eight brands of fish oil supplements contained excessive levels of PCB’s, including CVS, Nature made, Rite Aid, GNC, Twinlab and Solgar. The majority of these products were either cod liver or shark liver oils.
The Fish Industry, just like poultry & meat; believe in utilizing every morsel of the fish to maximize profit. The better cuts are sold to human consumers and generally the quality trickles down to animal feed or fertilizer.

At some point, fish oil, received its spike in attention and the Fish Industry recognized a very lucrative market for human consumption. More than 50% of the world’s fish oil is used as feed to farm raised fish, now there is a large human demand.

I was prescribed synthetic fish oil after heart bypass surgery to increase my HDL. (Side note: He also prescribed a statin that reduces not only LDL but HDL… what a struggle.) The majority of fish oil in the U.S. in consumed with the intent to raise “good” cholesterol. People eat salmon for the heart healthy benefits but do not realize that 70% of the salmon’s fat has nothing to do with Omega-3 fatty acids; and ultimately they are ingesting a large amount of unnecessary fat.

A Plant Based diet provides all the nutrients necessary to maintain health without over the counter supplements. The medical industry, wants to raise your HDL at all cost and fish oil will do that in a short amount of time. However, if you are following a plant-based diet your LDL will naturally decrease as well as your HDL.

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Ian Welch

Jun 13, 2012 10:56am EDT  --  Report as abuse
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