During the 1920s, a Canadian anthropologist observed that the Inuit communities of Greenland seemed to have tremendous health. This was despite eating an extremely low-carbohydrate diet which rarely included any fruits or vegetables. More commonly known as Eskimos, 75 percent of their average daily energy intake came from fat, yet cardiovascular issues were practically non-existent.
After taking blood samples many years later, it was discovered Eskimos took an exceptionally long time to stop bleeding from the needle site. Bleed time was around 50 minutes rather than the usual 3-5 minutes as their blood was so thin it would not clot. Scientists didn’t realize at the time, but it was the first discovery that dietary fish oil – and the omega-3 fatty acids within – could drastically affect human health.
Fast forward almost 100 years and fish oil is a household dietary supplement used to help promote heart health, relieve osteoarthritis pain and reduce inflammation. It is so popular in fact that, during 2013, $1.2 billion was spent on these capsules in the U.S. alone, despite a media storm mid-year suggesting fish oil supplementation caused prostate cancer. Many health professionals were quick to point out that the particular observational study was flawed.
More recently, fish oil has been heralded as a memory booster, with effects seen similar to that of learning a new language or solving Sudoku puzzles. Omega-3 fats are often used in clinical treatment to help maintain a patient’s brain function and cognition, with many studies finding one particular omega-3 fat, DHA, can significantly delay the onset of age-related dementia, including Alzheimer’s disease.
Dietary DHA is thought to be the most beneficial, as the predominant structural fatty acid that makes up our central nervous system, retina and brain is in fact DHA. The mechanisms are not well understood, but a new study may have found a big clue.
The study, published in the medical journal of the American Academy of Neurology, found that people with higher levels of omega-3 fatty acids may also have larger brain volumes in old age — equivalent to preserving one to two years of brain health.
1,111 women who were part of the Women‘s Health Initiative Memory Study had levels of omega-3 fatty acids (EPA and DHA) in red blood cells tested and recorded.
Eight years on, when the women were an average age of 78, MRI scans were taken to measure their brain mass and volume. It was found that participants with higher levels of omega-3s in the blood eight years ago had larger total brain volumes today. Those with twice as high levels of omega-3s (7.5 versus 3.4 percent) had a 0.7 percent larger brain volume (statistically significant).
“These higher levels of fatty acids can be achieved through diet and the use of supplements, and the results suggest that the effect on brain volume is the equivalent of delaying the normal loss of brain cells that comes with aging by one to two years,” said study author James V. Pottala, PhD, of the University of South Dakota in Sioux Falls and Health Diagnostic Laboratory, Inc., in Richmond, Va.
A shrinking brain volume is a sign of aging, and particularly with age-related cognitive decline such as Alzheimer’s disease. Participants with higher levels of omega-3s were also found to have a 2.7 percent larger hippocampus, the area of the brain crucial to memory. In Alzheimer’s disease, the hippocampus begins to degenerate even before symptoms appear.
These findings shed some light on the physiological role dietary omega-3 supplements can play on human health. By understanding how to preserve brain mass and function as we age, we could possibly reduce incidences of dementia, which are alarmingly on the rise.
The results have certainly got me wondering what the average weight of an Eskimo’s brain is compared to the rest of us?
Advice on taking fish oil supplements
Of course, natural sources of omega-3 fats which are found largely in marine life are the most affective, but supplements are an effective and affordable alternative.
If you’re already taking fish oil supplements, check out how your choice fares against competitor brands at LabDoor. They analyzed 30 best-selling fish oil supplements in the United States, looking at total omega-3 content, EPA and DHA quantities, vitamin D and CLA amounts, methylmercury concentration, and total oxidation values. It’s important to better understand the quality of fish oil you use, as well as where it is sourced from.
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