A team at the University of Southern California studied fish oil and brain health for two years. The study included 365 people ages 55 to 80. They rarely ate fish. They also had a higher chance of getting Alzheimer's disease, which affects memory and thinking. Some took fish oil every day. Others took a pill with no active treatment. The team chose the groups by chance.
Fish oil contains DHA, a type of fat. It helps brain cells work and send messages. After six months, the fish oil group had 17% more DHA, on average, in the liquid around the brain and spinal cord. But after two years, this group did no better on memory and thinking tests than the other group. Fish oil also did not stop a part of the brain from getting smaller. This part helps people form memories.
These results do not mean people do not need these fats. They also do not mean eating fish has no health benefits. The team is studying how the brain uses these fats and how food and health may affect this process. The researchers recommend regular exercise, good sleep, and a healthy mix of foods rather than depending on fish oil alone.
