Suffering asthma symptoms after exercise can make physical activity difficult, but a new study finds that vitamin C may help.
It’s estimated that about 10 percent of the population suffers from bronchoconstriction, a condition in which exercise triggers asthma symptoms, and that number rises to 50 percent for those participating in competitive winter sports.
Nine previous studies had found that vitamin C might improve this condition, so researchers from Finland decided to investigate further.
They performed a secondary analysis on 12 people who had asthma and suffered from bronchoconstriction, and administered a test to measure amount of obstruction in both their large and smaller airways before and after exercise.
The participants received vitamin C and placebo on alternating days. The researchers found that vitamin C increased the post-exercise small airway capacity in five of the individuals between by between 50 and 150 percent in individuals whose capacity declined severely during exercise. Seven individuals experienced no difference.
Given the cost and safety of vitamin C, Dr. Harri Hemila, the lead researcher, says that it “seems reasonable” for people with bronchoconstriction to try the supplement to see if it helps.
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