Several studies have found that in those with degenerative brain disease, levels of omega-3 fatty acids, particularly DHA, or always low. These studies suggest that ingesting sufficient levels of omega-3 fats prior to the onset of brain disease may offer preventive effects. DHA is capable of preventing dementia through various mechanisms. For example, DHA can temper the activity of enzymes in the brain that activate a protein called tau. This is significant because tau is the major constituent of neurofibrillary tangles in the brain, which are considered a hallmark of Alzheimer's disease. DHA also reduces inflammation in the brain, a major cause of most brain degeneration. One way it does this is by reducing the level of an omega-6 fat in the brain called arachadonic acid. This fatty acid is the precursor to various inflammatory substances that are directly related to brain inflammation. DHA also reduces oxidative stress in the brain, and increases levels of brain-derived neurotropic factor, which works to repair damaged brain neurons.
While it's clear that the omega-3 fats nourish and protect the brain, some have suggested that ingesting fish oil can increase intelligence. Based on this, a recent study examined 867 people, ages 70 to 79, some of whom were provided with a placebo, while others were provided capsules containing 200 milligrams of EPA and 500 milligrams of DHA for two years. The results of the study found no difference in cognitive or thinking ability between the groups ingesting omega-3 and those ingesting the placebo, which consisted of olive oil. All the subjects in the study were healthy, and not suffering any kind of brain problems. Cognitive function didn't decline in either the omega-3 group or the placebo group, leading to the conclusion that fish oil doesn't offer any benefits to older people.
But the study actually proves little or nothing for several reasons. For one, the dose provided of omega-3 fatty acids (EPA and DHA) is too meager to promote any changes. For treatment of Alzheimer's, some have suggested doses of omega-3 over 15 grams a day, far more than was provided in this study. Even for healthy people, the dose used in this study was about one-sixth the suggested daily dosage. In addition, brain changes occur slowly, and a two-year study wouldn't provide enough time to detect any beneficial effects from using fish oil, except perhaps for treating depression. Finally, studies show that fish oil works best for preventive purposes against brain pathology in those who have the apolipoprotein A4 gene. Having this gene, especially two copies, makes you at higher risk for Alzheimer's disease. But based on the fact that the brain has such a rich content of DHA, and that studies do show protective effects, you would have to be crazy not to ingest fish oil supplements
©,2013 Jerry Brainum. Any reprinting in any type of media, including electronic and foreign is expressly prohibited.
