The Meals Study for Amyotrophic Lateral Sclerosis and Parkinson's Disease

Brief summary template The goal of this trial is to test the feasibility and efficacy of the Mediterranean-DASH Intervention for Neurodegenerative Delay (the MIND diet) in people living with amyotrophic lateral sclerosis (ALS) and Parkinson's disease (PD) and healthy controls. The main question\[s\] it aims to answer are: * How feasibile is our educational dietary intervention, which teaches participants with ALS, PD, and healthy controls to eat by the neuroprotective MIND dietary pattern? * How does the MIND dietary pattern affect the gut microbiome, metabolome, and lipidome in people with a neurodegenerative disease (ALS or PD) and healthy controls? * Does the MIND diet affect clinical measures of ALS and PD? * Does the MIND diet affect human biomarkers of systemic inflammation, metabolism, and neurodegeneration? Participants will: * Receive a MIND diet cookbook, a folder with educational handouts, and weekly emails with links to educational videos about the MIND diet. * Complete a food diary, a MIND diet tracker, and a weekly questionnaire about their experience of eating by the MIND diet. * Collect stool specimens at the beginning, middle, and end of the study. * Undergo venipuncture at the beginning and end of the study.