A new study reveals that eating at least one serving of seafood a week could reduce the risk of Alzheimer's disease, CNN reports.

Previous studies have revealed that omega-3 fatty acids found in fish could play a role in protecting against Alzheimer's and other forms of dementia. However, researchers remain in doubt over whether the presence of mercury in fish could cancel out the benefits of eating fish.  

The new study suggests that the presence of mercury in fish does not diminish the benefits of eating fish.

"The findings were very striking," said Martha Clare Morris, director of nutrition and nutritional epidemiology at Rush University Medical Center.

"Our hypothesis was that seafood consumption would be associated with less neuropathology, but that if there were higher levels of mercury in the brain, that would work against that. But we didn't find that at all," said Morris, who is lead author of the study.

The study was published Tuesday in the Journal of the American Medical Association.

For the study, the researchers analyzed a group about their diet every year starting in 1997. The researchers performed brain autopsies in 286 participants who died between 2004 and 2013 to look at the levels of mercury and whether there was any neurological damage.

The researchers found that even though there was indeed more mercury in the brains of participants who reported eating more seafood, it did not appear to have any effect on whether there was neurological damage.

"One theory is that seafood consumption may be more beneficial in older age because, as we age, we lose DHA in the brain," a molecule that is important to maintain brain health, Morris said.

DHA is one of the main fatty acids that can be obtained from fish.

"The evidence is quite clear that people who consume healthier forms of fish [which are baked or broiled rather than fried] are going to end up with healthier brains," said James T. Becker, professor of psychiatry and associate director of the Alzheimer's Disease Research Center at the University of Pittsburgh, who was not involved in the current study.

As for whether mercury is linked to dementia, Becker said,

"I personally don't think there's evidence for it. I think these heavy metals are going to do other things first," such as causing nerve pain, itching or burning."

.