Patients with amyotrophic lateral sclerosis (ALS) whose diets are rich in fruits, vegetables, and omega-3 fatty acids appear to have an edge over patients who prefer a steak dinner.1 Specifically, patients with antioxidant, micronutrient-rich diets have better functionality at or around the time of diagnosis. The hope is that better nutrition could translate into slower disease progression and less disability. The findings from the Amyotrophic Lateral Sclerosis Multicenter Cohort Study of Oxidative Stress (ALS COSMOS) were published in JAMA Neurology.
ALA COSMOS researchers sought to examine the impact of macronutrient vs micronutrient intake to shed further light on the role of nutrition in the pathogenesis and progression of ALS. They pointed out that diets high in carbohydrates, glutamate, and saturated fats (“bad” macronutrients) and low in vitamin E, omega-3 polyunsaturated fatty acids, and carotenoids (“good” micronutrients) have been associated with ALS risk, although the results of numerous studies seeking confirmation have not been consistent.
The team conducted a cross-sectional baseline analysis of 302 patients with ALS whose symptom duration before diagnosis was 18 months or less. Nutrient intake was measured using a modified Block Food Frequency Questionnaire, function was measured using the ALS Functional Rating Scale–Revised (ALSFRS-R), and respiratory function was measured using percentage of predicted forced vital capacity (FVC). Men comprised 59% of the study cohort, and the median age of the participants was 63 years (range, 5.5-68.0 years). Median body mass index was 26 (range, 23.5-28.5), and median symptom duration was 11 months (range, 7.8-15 months). Seventy-two percent had signs of spinal disease onset and 28% has bulbar onset, with about half of the cohort reporting that they experienced eating problems or occasional choking early in the disease course.
Median ALSFRS-R score (37; range, 33-41) and median percent FVC (82%; range, 66%-97%) indicated that participants had modestly severe ALS and low normal respiratory function at baseline. However, regression analysis revealed that antioxidant and carotene intake from diets rich in fruits and vegetables were positively associated with ALSFRS-R scores (P = .05 and P = .03, respectively) and percent FVC (P = .02 and P = .03, respectively). Good micronutrient intake was positively associated with ALSFRS-R scores (P < .001) and percent FVC (P < .001) for both parameters), and 6 micronutrients were key: lycopene, omega-3 fatty acids, omega-6 fatty acids, isoflavones, and fiber from vegetables and grains. Regression analysis of good food groups showed that eggs, fish, poultry, nuts and seeds, beneficial oils, fruits, and vegetables in general were positively associated with ALSFRS-R scores and percent FVC.
Although macronutrient intake did not impact ALSFRS-R score or percent FVC; regression analysis showed that bad food groups were negatively and significantly associated with ALSFRS-R score (P = .002) but had no impact on percent FVC. The foods most negatively correlated with ALSFRS-R score were milk, lunchmeats, and beef and pork.
“Nutritional care of the patient with ALS should include promotion of fruits, vegetables, high fiber grains, and lean protein sources such as fish and chicken,” study author Jeri W. Nieves, PhD, told Neurology Advisor. Dr Nieves is associate professor of clinical epidemiology and nutrition at Columbia University in New York City.
The findings add weight to the argument that antioxidants may be salutatory in relation to ALS risk and, conversely, that oxidative stress may be a contributing factor; however, the study authors stressed that their findings highlight an association between diet and function in patients with ALS, not ALS causality. “Although our findings need to be confirmed in longitudinal studies, these dietary recommendations reflect current ones for overall health,” she added.
Nieves JW, Gennings C, Factor-Litvak P, et al; Amyotrophic Lateral Sclerosis Multicenter Cohort Study of Oxidative Stress (ALS COSMOS) Study Group. Association Between Dietary Intake and Function in Amyotrophic Lateral Sclerosis. JAMA Neurol. 2016 Oct 24. doi:10.1001/jamaneurol.2016.3401. [Epub ahead of print]