Consuming omega-3 fatty acids may help prevent brain lesions, a hallmark of Alzheimer's disease.
Omega-3 was found to reduce two types of brain lesions associated with Alzheimer's firstly by limiting a protein which leads to neurofibrillary tangles and secondly by preventing the formation of clumps of protein in the brain.
Food containing omega-3 fatty acids include fish, meat, organ meats, micro-algae and various food supplements.
This is the first research to show that consuming omega-3 fatty acids could actually prevent the onset of the disease.
Frank LaFerla, co-author of the study, said: "We are greatly excited by these results, which show us that simple changes in diet can positively alter the way the brain works and lead to protection from Alzheimer's disease pathology.
Professor LaFerla has previously shown that the onset of Alzheimer's could be slowed in mice through short, repeated learning sessions, suggesting human sufferers also have the capability of slowing the advancement of the disease.
Kim Green, lead author of the study, said: "Combined with mental stimulation, exercise and other dietary intakes and avoiding stress and smoking, we believe that people can significantly improve their odds against the disease."