In some cases, there may be a connection between oxidative stress and dementia. A study appearing in the Archives of Gerontology and Geriatrics (2001;Suppl. 7:325-331) compared 30 subjects between the ages of 90 and 107 years with dementia to 32 healthy people in the same age range and found that men with dementia had higher thiobarbiuric acid-reactive substances and lower vitamin E levels (indicators of oxidative stress). Lipid peroxidation seemed to play a role in dementia in men, but not in women. Research published in Neurobiology and Aging (2005; 26(7): 987-94) looked at 1033 subjects over the age of 65 and found that a low level of vitamin E in the blood was associated with an increased incidence of dementia.
Another study that appeared in the American Journal of Geriatric Psychiatry (Vol. 18, Issue 5, Pages 413-420) looked at dementia in Swedish twins. There were 3,779 subjects; 355 of whom were diagnosed with dementia. The study found that greater consumption of fruits and vegetables reduced the chance of developing dementia. Another study, appearing in Neurology (2000;54:1265-1272) looked at 3,385 men between the ages of 71 and 93, found that taking a combination of vitamins A and C had a protective effect against vascular dementia. The supplementation also had some protective effect against mixed or other dementia, but not against Alzheimer’s disease.