Thursday Dec 5, 2013 (foodconsumer.org) -- Taking dietary supplements vitamin E and vitamin C together or taking niacin can reduce risk of developing dementia and improve cognitive function in people without dementia, according to a study in Neurology.

Dr. Kamal H. Masaki, The Honolulu Heart Program in Honolulu, HI and colleagues conducted the study and found study participants who reported taking both vitamin E and C supplements were 82% less likely to be diagnosed with vascular dementia, compared with those who did take either.

These vitamins cut the risk of mixed/other types of dementia by 69%, but there was no association between taking vitamin E and C and risk of Alzheimer's disease, the study shows.

Among participants who did not have dementia, taking vitamin E and vitamin C was associated with significantly better cognitive function.

The study was based on data from 3,385 Japanese-American men aged 71 to 93 years who lived in Hawaii and enrolled in The Honolulu–Asia Aging Study.

The study concluded "These results suggest that vitamin E and C supplements may protect against vascular dementia and may improve cognitive function in late life."

Another nutrient that helps prevent dementia is niacin or vitamin B3.  Research shows that people with the highest levels of serum niacin were much less likely to develop dementia or have cognitive decline.  

Niacin is known to be involved in DNA synthesis, repair and neuron signaling.  The nutrient also improves circulation and lowers cholesterol.  But in order to have a protective effect against dementia, the dose of niacin needs to be between 100 to 300 mg per day. (David Liu, PHD)