Free radicals are unstable oxygen compounds that damage fats, proteins and DNA. The brain is especially sensitive to free radical (oxidative) damage because of its high content of fatty acids, its high use of oxygen and its low levels of antioxidants. By studying the brain tissue of both live and deceased Alzheimer’s patients, researchers now know that antioxidants, including vitamins C and E, can play a significant role in the prevention of the disease.

To further this line of research, scientists at the Erasmus Medical Center in the Netherlands used a population-based study to identify whether or not antioxidants could reduce the detrimental effects of free radical damage on the brain. Researchers reviewed at total of 5,395 healthy people aged 55 years or older from 1990 to 1999, looking for signs of Alzheimer’s and/or dementia, and then trying to identify if there was a relationship between intake of antioxidants (such as beta-carotene, flavonoids, vitamin C and vitamin E).

In the first six years, 197 patients showed signs of dementia, with 146 of those developing Alzheimer’s. After analyzing lifestyle and dietary habits as well as family history, researchers concluded that there was a clear connection between vitamin C and E intake and reduced incidence of Alzheimer’s. They also found that both beta-carotene and flavonoids had preventative benefits. The researchers note that the relationship between intake of antioxidants and reduced risk of Alzheimer’s was most pronounced in smokers.

Sources: J Am Osteopath Assoc 2001 Dec;101(12 Suppl pt 1):S11-5; JAMA 2002 Jun 26;287(24):3223-9