Fish Oil May Fight Alzheimer's Disease
Dietary Supplements Helped Protect Brains of Elderly Mice
Omega-3 Fatty Acids in the Spotlight continued...
Lim's team studied elderly mice with genes linked to an Alzheimer's-like brain condition. The mice were split into three groups.
One group of mice was fed normal chow. A second group got a diet low in DHA. The third group ate a diet high in DHA.
After three to five months -- the equivalent of several years for people -- the group that ate the most DHA had the healthiest brains. That is, they had the least amount of senile plaque and harmful proteins, which clump and knot in the brain in Alzheimer's disease.
Brain imaging showed that the high-DHA diet cut brain plaque by 40%. The largest drops were seen in brain areas vulnerable to Alzheimer's disease, according to the study.
The high-DHA diet also delivered the biggest drop (70%) in levels of beta-amyloid protein in the brain, a building block of plaque, compared to the other groups.
How Much Does It Take?
There is no official recommended daily allowance of DHA (or any omega-3 fatty acid). If you choose to eat fish, you may want to keep an eye on your intake due to concerns about contaminants such as mercury.
DHA and another omega-3 fatty acid, EPA, are found in fish, eggs fortified with omega-3 fatty acids, and fish oil supplements. Another omega-3 fatty acid, ALA, is found in walnuts, soybean oil, and flax seeds.
What About People?
Swedish researchers are studying the safety and tolerability of omega-3 fatty acids on people with mild to moderate Alzheimer's disease. Two studies are also comparing omega-3 fatty acids with placebos, note Lim and colleagues.
Lim is a postgraduate researcher at the University of California Los Angeles (UCLA). Other researchers included Greg Cole, PhD. He's a UCLA professor of medicine and neurology. Cole is also the associate director for research with the Geriatric Research, Education, and Clinical Center at the Greater Los Angeles Veteran's Administration Healthcare System.
The study appears in The Journal of Neuroscience's online edition for March 23.