If you want to be a little smarter, increase the amount of magnesium in your diet. The nutrient is one of the most vital for healthy brain functioning, something that becomes increasingly important as we get older. High magnesium levels in your body can improve cognitive abilities and memory, and can stop the brain from deteriorating as we age, a new study confirms. Beijing University recently tested magnesium levels on laboratory rats to see how their brain functioning improved. The rats given a high-magnesium diet displayed improved cognitive abilities compared with rats fed a standard diet, which is usually thought to contain sufficient magnesium for our body's needs. Aside from supplements, magnesium can be found in spices, nuts, in coffee and tea, and in green leafy vegetables, such as spinach. (Source: Neuron, 2010; 65: 165-77).