Opt for wholegrain food: Make sure you’re eating a diet rich in a mix of wholegrain foods such as cereals, and whole wheat pasta. One study found that women who increased their folic acid, vitamin B12 and vitamin B6 intake showed an improvement in recalling information compared to women who were not taking a supplement.Enjoy oily fish: The essential omega-3 fatty acids - found in oily fish (such as sardines), as well as fish oil, walnut oil and flaxseeds (linseeds) - are high in DHA, a fatty acid crucial to the health of our nervous system. Low DHA levels have been linked to a higher risk of developing Alzheimer’s disease and memory loss. Fish also contains iodine, which is known to improve mental clarity.Eat more tomatoes:There is good evidence to suggest that lycopene, a powerful antioxidant found in tomatoes, could help protect against the kind of free radical damage to cells which occurs in the development of dementia, particularly Alzheimer’s.Eat more greens: They are a great source of vitamin K. Pick up pumpkin seeds: Just a handful a day is all you need to get your recommended daily amount of zinc, vital for enhancing memory and thinking skills.Go nuts: A study published in the American Journal of Epidemiology suggests that a good intake of vitamin E might help to prevent poor memory. Nuts are a great source of vitamin E along with leafy green vegetables, seeds, eggs, brown rice and whole grains.