As humans age, mental acuity and cognitive function can decline and is manifest as forgetfulness, inattentiveness, language impairment, and decreased learning and problem solving ability. In some individuals, this can progress to mild cognitive impairment and even to dementia. Dementia is a pathological process and should not be thought of as a normal process of aging. Dementia is a cognitive impairment syndrome and can result from Alzheimer’s disease, cerebrovascular disease, or deposition of Lewy bodies. The brain is composed approximately of 60% fatty acid, and as we age the body’s ability to replenish these fatty acids decreases. This has been postulated as a possible mechanism for the development of dementia in older individuals. Previous observational studies have shown that dietary supplementation with omega 3 fatty acids can delay or even prevent the development of mild cognitive impairment and dementia. A recent review examined the results of three studies comparing the effects of omega 3 fatty acids to placebo on cognitive decline in the elderly. Researchers from the London School of Hygiene and Tropical Medicine in England, lead by Dr. Emma Sydenham, have found that individuals who consumed omega 3 fatty acids did not score better on tests of mental acuity compared to the placebo group. The three studies followed 3,536 participants who were randomized to the treatment group or a placebo group. Cognitive function was assessed by a mental state examination at baseline and study conclusion. For all three studies, there were no overall benefits identified in cognitive function for the treatment group. Some critics of the study have pointed out the study participants were relatively young and if an older study group was used a benefit may have been observed. More research is needed to definitively determine if a cognitive benefit exists for older individuals who supplement their diet with omega 3 fatty acids.
See the following news clip from Dr. Allen Mask regarding the study results:
Sydenham E, Dangour AD, Lim W-S. Omega 3 fatty acid for the prevention of cognitive decline and dementia. Cochrane Database of Systematic Reviews 2012, Issue 6. Art. No.: CD005379. DOI: 10.1002/14651858.CD005379.pub3