Nutrition and dementia.

The nutritional consequences of dementia and the role of diet in the etiology, treatment, and prevention of dementia are the subjects of this review. The major cause of dementia is Alzheimer's disease. Although it has been suggested that aluminum intake may cause this disease, the bulk of scientific evidence suggests that this is unlikely. Dietary supplements of choline and lecithin have been used to treat Alzheimer's disease but are ineffective. Alzheimer's disease patients are at risk of developing protein-energy malnutrition because of poor food intake and increased energy requirements. The second most common cause of dementia is multi-infarct dementia, caused by multiple strokes. Diet may play a role in the prevention of this form of dementia through effects on blood pressure and other risk factors. Control of risk factors may also prevent further progression of the dementia. Patients with multi-infarct dementia often have dysphagia. The third most common cause of dementia appears to be excessive alcohol intake, due both to the direct neurotoxic effects of alcohol and to the effects of alcohol on nutritional status. Alcoholic dementia may be at least partially reversible with abstinence and good nutrition. Other causes are vitamin B-12 and folate deficiencies; these are reversible dementias. In all types of dementia, adequate nutrition may improve physical well-being, help maximize the patient's functioning, and improve the quality of life.