"Older people who eat baked or broiled fish at least once a week may be boosting their brain https health. In a new study imaging scans showed that regular fisheaters were less likely to have brain cells die off in the area of the brain responsible for shortterm memory  recalling a phone number that was just heard for example. And people who ate baked or broiled fish at least weekly and didnt lose brain cells were much less likely to develop Alzheimers https disease or mild mental impairment says Cyrus Raji MD PhD of the University of Pittsburgh School of Medicine. Several studies have linked a diet https rich in certain fish to a reduced risk of Alzheimers disease. This benefit is thought to come from the omega fatty acids in fish although studies of fish oil supplements https_assetscontrolled_contenthealthwisespecialDietary_SupplementsTopic_Overview.xml have produced disappointing results in people who already have Alzheimers. The new study is the first to establish a direct relationship between fish consumption brain structure and Alzheimers risk Raji says. More fish more brain less Alzheimers he tells WebMD. Eating Fish for Brain Health As many as . million Americans may have Alzheimers disease an incurable progressive brain disease https that slowly destroys memory. People with mild mental impairment have memory loss https greater than expected by normal aging but to a lesser extent than in Alzheimers disease. The study involved  people average age  with no memory problems in . All filled out food questionnaires asking how much fish they ate and how they prepared it. There were  people who ate fish at least weekly most of whom ate it one to four times a week. Imaging scans of the brain were taken at the start of the study and an average of about seven years later. What we found Raji says is that if you dont eat fish brain cells die off and  developed Alzheimers disease or mild impairment over the next five years. On the other hand only  of people who ate fish weekly and whose brain cells were preserved developed Alzheimers or mild impairment. The researchers tried to take into account other risk factors for memory loss that could affect the results including age gender education obesity and physical activity https Still the association between fish brain volume and dementia https remained. But it is possible that other lifestyle factors such as eating less meat could have also contributed to the association between eating fish and brain health. William Thies PhD chief medical and scientific officer of the Alzheimers Association says the findings support the groups recommendation to eat a diet rich in coldwater fish that contain beneficial omega fatty acids. These fish include halibut mackerel salmon trout and tuna. But its still not clear how much fish would have to be eaten to have a detectable benefit he tells WebMD. Not all fish is healthy Raji says. Some fish contain toxins that could raise the risk of dementia. And fried fish has no benefit for preserving memory he says. The Environmental Protection Agency recommends that pregnant https women nursing mothers and children avoid eating shark swordfish king mackerel or tilefish and limiting albacore tuna to  ounces per week because of concern about levels of mercury in these fish. These findings were presented at a medical conference. They should be considered preliminary as they have not yet undergone the peer review process in which outside experts scrutinize the data prior to publication in a medical journal."