Carotenoids—the substances that give many vegetables and fruits their vivid red, orange, and yellow colors and are also found in many dark green vegetables—may play a key role in preventing or delaying amyotrophic lateral sclerosis (ALS), commonly known as Lou Gehrig’s disease, according to new Harvard School of Public Health (HSPH) research. The study was published online January 29, 2013 in the Annals of Neurology.
Previous research suggests that oxidative stress may play a role in the onset of ALS, a progressive neurological disease that causes muscle degeneration and paralysis and afflicts roughly 20,000 to 30,000 Americans. Since carotenoids function as antioxidants, the HSPH researchers examined whether there might be links between these substances and risk of ALS.
The study was led by Kathryn Fitzgerald, SM ’11, a doctoral student in epidemiology and nutrition at HSPH; senior author was Alberto Ascherio, HSPH professor of epidemiology and nutrition. The researchers analyzed data from five long-running studies that collectively included more than 1 million participants. They found that people with the highest dietary carotenoid intake had a 25% reduced risk of ALS, and that two particular types of carotenoids—beta-carotene, found in foods like sweet potatoes, squash, and carrots; and lutein, found in dark green vegetables like broccoli, spinach, and kale—were associated with a 15% and 21% reduced risk of ALS, respectively.