Written by Susan Sweeny Johnson, PhD, Biochem.
ALS (amyotrophic lateral sclerosis), commonly know as Lou Gehrig’s Disease, is characterized by breakdown of the nerves that control muscles. Usually brain function is not affected. Most patients die from respiratory failure in 3-5 years from onset of symptoms. About 5,000 new cases of ALS are diagnosed in the US per year, most commonly in males between 40 and 60 years old. In 75% of all cases, there is no genetic link and also no clear cause.
Many studies have focused on finding a dietary link. So far, one study has found a relationship between glutamate and fat intake and onset of ALS. (1) Since other neurodegenerative diseases such as Alzheimer’s and Parkinson’s are affected by fat intake,(2,3) the researchers in this study looked at the normal dietary intake of saturated and unsaturated fatty acids, cholesterol, glutamate, phytoestrogens, calcium and antioxidants and their effect on the risk of developing ALS.
One hundred and eighty-four patients with ALS symptoms and no family history of the disease were sent questionnaires about their food intake during the year prior to the onset of first muscle weakness. They were asked to find two non-symptomatic people of similar age and gender to act as controls. These 220 controls were to fill out a dietary questionnaire covering the same time period as their ALS contact.
All questionnaire results were compiled and recorded blindly and analyzed for statistical significance. Glutamate intake was not different in the two groups, although excess glutamate has been shown to break down nerves in ALS patients. This could be because glutamate accumulation is not due to dietary intake.
The two dietary factors that differed the most between the ALS group and the controls were polyunsaturated fat and vitamin E intake. The ALS group consumed significantly less of these. When both polyunsaturated fat and vitamin E were taken together, there was a 50-60% decreased risk of developing ALS.
Source: Veldink, Jan H., Sandra Kalmijn, Geert-Jan Groeneveld, Wendy Wunderink, Annemarie Koster, Jeanne HM de Vries, Jolanda van der Luyt, John HJ Wokke, and Leonard H. Van den Berg. “Intake of polyunsaturated fatty acids and vitamin E reduces the risk of developing amyotrophic lateral sclerosis.” Journal of Neurology, Neurosurgery & Psychiatry 78, no. 4 (2007): 367-371.
© 2007 Journal of Neurology Neurosurgery and Psychiatry
Posted August 6, 2008.
References:
- Nelson LM, Matkin C, Longstreth WT, Jr., et al. Population-based case-control study of amyotrophic lateral sclerosis in western Washington State. II. Diet. Am J Epidemiol 2000;151:164-73.
- Lau de LML, Bornebroek M, Witteman JCM, et al. Dietary fatty acids and the risk of Parkinson disease. Neurology 2005;64:2040-5.
- Kalmijn S, Launer LJ, Ott A, et al. Dietary fat intake and the risk of incident dementia in the Rotterdam Study. Ann Neurol 1997;42:776-82.
