A large study questions the power of omega-3s to protect aging brains against cognitive decline and dementia.
The study, published in JAMA in August, included 3,073 people with an average age of 73. Unlike previous studies that did find that omegas helped maintain brain power, this one did not rely on participants’ recall of what they ate to determine how much omega-3s they consumed. Instead, researchers randomly assigned subjects to take omega-3 pills or a placebo for five years. They tested participants on cognitive skills at the start of the study and came back every two years for additional analysis. Researchers found no significant differences in the cognitive scores between the omega-3 group and the placebo.
It’s possible that in this new study, it was too little, too late in terms of seeing any effects of the omega-3s on cognition, notes a time.com article about the results. Just as the decline associated with dementia can take years or decades to take effect, the same may be true for the impact of the omegas. “The bottom line is that supplements are not the fast cure,” Dr. Emily Chew, deputy director of the division of epidemiology and clinical applications at the National Eye Institute (part of the National Institutes of Health) told time.com. “You are what you eat, and you’ve got to eat well. Maybe it was too late for some of the people in our study.” The study did not examine the impact of foods high in omega-3s, only of omega-3 supplements.
Last year, a study published in the journal Neurology found that people with higher levels of the omega-3 fatty acids may also have larger brain volumes in old age equivalent to preserving one to two years of brain health.