Respiratory problems associated with air pollution are becoming increasingly common. Scientific studies have shown that antioxidants could have a beneficial effect on lung health and help counteract some of the harmful effects of pollution. An individual breathes 15,000 liters of air every day, and the gas exchange area of the respiratory system is nearly 70 m2. Polluted air contains powerful oxidants such as nitrogen dioxide and ozone, which appear to play a significant role in respiratory diseases.
Antioxidants and lung health
Several studies have demonstrated that a high intake of antioxidant nutrients, such as Vitamin E and beta-carotene, protects lung cells and promotes normal lung function. Lung function is assessed through respiratory functional tests using a spirometer, measuring the maximal expiratory volume per second (FEV1) or forced vital capacity (FVC).
A study involving 18,000 Americans showed that each antioxidant—Vitamin E, beta-carotene, Vitamin C, or Selenium—was strongly associated with normal lung function as measured by a standard test. The benefits provided by antioxidants were more pronounced in non-smokers. In another study, seniors with the highest blood levels of beta-carotene and alpha-carotene had significantly better lung function.
Antioxidants and resistance to pollution
Researchers followed 47 outdoor workers in the city of Mexico, a polluted urban area with high ozone levels. Nearly half of these men received a daily nutritional supplement containing 75 mg of Vitamin E, 15 mg of beta-carotene, and 650 mg of Vitamin C for two and a half months, while the other group received a placebo. Antioxidant nutrient supplementation significantly improved lung capacity despite daily exposure to ozone pollution.
In 227 elderly or middle-aged subjects, it was found that those with the highest blood levels of beta-carotene, whether from diet or supplementation, were the least likely to experience respiratory difficulties caused by air pollution. These various studies show that antioxidants can help our bodies fight oxidative stress caused by air pollution and contribute to maintaining healthy lung function.