Vitamin C is one of the most important antioxidants on Earth, and its ability to aid tissue growth and repair is well-known. However, British researchers at the Imperial College of London have found another good reason to eat more oranges and lemons – vitamin C can also guard us against the negative effects of air pollutants such as car exhaust and power plants.
The researchers studied 209 London-based patients between the years of 2008 and 2009 to determine the link between oxidative stress and coarse particulate matter (air pollution produced mainly through fossil fuel combustion). Most of the patients were between the ages of 54 and 74, and all of them were hospitalized due to asthma or COPD (chronic obstructive pulmonary disease).
The researchers found that there was a 35 percent increased risk of hospitalization for asthma or COPD for every additional 10 micrograms per cubic meter (mcg/m3) in coarse particulate matter to which the patients were subjected. They also found that the risk of hospitalization was 1.2 times greater among patients with low vitamin C levels – a correlation that remained true even when elderly patients and former smokers were excluded from the analysis.
“The protective effect of vitamin C was still present after excluding smokers and elderly subjects, implying that the effect of this antioxidant was not explained by smoking or age,” said Dr. Cristina Canova, study co-author and research associate at the university’s Respiratory Epidemiology and Public Heath Group.
The U.S. Environmental Protection Agency and its European equivalents have set the ‘safe’ standards for air pollution levels as 50 mcg/m3 for coarse particulate matter.
Why vitamin C helps
Studies have shown that free radicals contribute to cancer, heart disease and respiratory diseases such as asthma and COPD. Since vitamin C is an antioxidant that has the ability to neutralize free radical activity, it is plausible, if not likely, that people who regularly consume vitamin C-rich foods are better guarded against pollution (air-based or otherwise) than those who suffer from a deficiency.
Regular vitamin C intake is also important, because our bodies don’t have the ability to make or store it themselves. For this reason, it is important that people – especially those who live in places with high concentrations of coarse particulate matter, such as cities – avoid periodic ‘binges’ in vitamin C foods and favor a more evenly-distributed, and ideally daily, intake instead.
Foods rich in vitamin C include dark leafy greens (especially raw kale), all citrus fruits, bell peppers, red and green hot chilli peppers, fresh herbs (especially parsley and thyme), cauliflower, papaya, and strawberries.
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