Could lysine supplementation prevent Alzheimer's dementia? A novel hypothesis

There is a growing body of evidence that implicates the herpes simplex type 1 virus (HSV-1) in the development of Alzheimer's dementia (AD). HSV-1 has been found to be present in the cerebrum of the great majority of older adults, and in many of the same areas of the brain that are affected by AD. When active, the virus may contribute to the formation of the neurofibrillary tangles and amyloid plaques characteristic of AD. Like AD, HSV-1 encephalitis may cause long term memory loss. HSV-1 replication is suppressed in lysine-rich/arginine-poor environments, and population studies suggest that diets high in lysine and low in arginine may be associated with lower rates of AD. There are no prospective studies of the efficacy of lysine supplementation to prevent or reduce the incidence of AD. Supplementation with adequate doses of lysine could prevent the development of AD.