A new study published in the journal JAMA Neurology has shown that the addition of antioxidant nutrients, foods high in carotenoids and fiber, and fruits and vegetables to the daily diet of those with amyotrophic lateral sclerosis (ALS) could enhance function and slow the progression of the neurological disease.
Amyotrophic lateral sclerosis (ALS) is a debilitating progressive neurodegenerative disorder of the lower and upper motor neurons found within the spinal cord, brainstem, and midbrain. In ALS, the motor neurons in these regions become dysfunctional and gradually die, and once this happens the muscles are no longer able to receive nerve impulses from the brain. The patient’s muscles later weaken and atrophy (waste away), leading ultimately to muscle paralysis. A large percentage ALS of patients die from respiratory failure, typically between 3 to 5 years from the onset of symptoms. Though, around 10 to 20 percent of patients can live longer than 10 years.
In recent years, there has been growing interest in the possible role of environmental factors and nutrition in the pathogenesis (development) and progression of ALS. Some evidence from previous studies suggests that the risk of developing ALS increases with increased consumption of macronutrients, such as fat, glutamate, and carbohydrates, and with low consumption of several micronutrients, including carotenoids, vitamin E, ω-3 polyunsaturated fatty acids, as well as vegetables and fruits. However, previous research has not examined whether foods or nutrients are linked with ALS or respiratory function shortly following diagnosis.
In order to understand the link between nutritional intake and ALS function and respiratory function at diagnosis, a group of researchers conducted a cross-sectional analysis using nutrition data from 302 patients (178 of them male, average age around 63) from the Amyotrophic Lateral Sclerosis Multicenter Cohort Study of Oxidative Stress study. Each participant had symptoms of, and was diagnosed with, ALS for 18 months or less. A modified version of a food questionnaire, known as Block Food Frequency Questionnaire (FFQ), was used to collect information about the participants’ nutrient consumptions and diet characteristics. Respiratory function was measured using the percentage of predicted forced vital capacity (FVC) and ALS function was assessed using the ALS Functional Rating Scale–Revised (ALSFRS-R).
The study, published in the journal JAMA Neurology, found that higher consumption of antioxidant nutrients, foods rich in carotenoids and fibers, vegetables and fruits seem to be related to improved ALS function and slower progression of the disease near the time of diagnosis. However, lunch meats and milk were found to promote more severe progression of the disease and lower measures of function, possibly due to a greater intake of fat and the possibility for these foods to promote oxidative stress. This finding points to diet in helping reduce the severity of ALS and suggests the function of oxidative stress in ALS severity.
The researchers assert that cause and effect cannot be established by their study results. Moreover, a food questionnaire was used to collect data on dietary habits over time, but this approach may not always represent accurate daily diets. The researchers conclude that diets rich in vegetable and fruits, which are abundant in fibers, antioxidants, and carotenes, should be promoted by those who take nutritional care of patients with ALS.
Written By: Nigar Celep, BASc