Many people believe that memory function can be improved by increasing your levels of vitamin B12. Though there is evidence to suggest that people who suffer from Alzheimer's disease and dementia are often deficient in this vitamin, studies have found that taking supplements or increasing dietary vitamin B12 does not improve memory function in those living with the disease, according to the Mayo Clinic. However, it may be useful in helping to prevent the disease, according to one study. MORE: Six future tests that could help diagnose Alzheimer's disease earlier. Vitamin B12 helps to maintain healthy red blood cells and nerve cells, however, many people are deficient in the vitamin — particularly older people and vegetarians whose restricted diet may contain little of the vitamin that's found primarily in animal products. It's advisable that older adults consult their doctors to find out if they are deficient in the vitamin as it's important for overall health. They may be advised to take supplements or include more B12 in their diet by eating more meat, liver, eggs, and dairy products, or if they're vegetarian, by consuming products like fortified cereals. MORE: Could drinking tea help reduce the risk of Alzheimer's disease? Alzheimer’s News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or another qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.