Matthew Messer

Matthew Messer


Vitamin C is a well-known antioxidant, but few people know that it can also afford us some protection against environmental pollutants. This is particularly useful information for people living in big cities or for those who breathe in a lot of pollutants in the course of their work.

Vitamin C supplementation against the effects of air pollution

It is well known that vitamin C is an important part of our body's defense system, which fights off various infections and environmental toxins daily. However, there is currently no consensus on exactly how much and in what form it may be advisable to supplement.  

A new study suggests that high-dose supplementation looks promising, but many warn against it, saying it makes no sense.

This randomized trial, published in 2022, tested the supplementation of 2000 mg of vitamin C per day in a large Chinese city of 11 million people. The study involved 58 healthy young people who received 2 g of vitamin C or a placebo daily for 1 week, divided into 4 portions for proper absorption.

The main aim of the study was to see if vitamin C supplementation improves inflammatory markers and other cardiovascular health-related measures that are known to be adversely affected by air pollution.

The investigation yielded a positive result

Levels of inflammatory markers relevant to the cardiovascular system were as follows:

  • A 19.47% decrease in interleukin-6(IL-6) levels,
  • (IL-1,6-6), a 17.30% decrease in tumor necrosis factor-alpha (TNF-α),
  • C-reactive protein (CRP) decreased by 34%.

In addition, the following positive changes were observed:

  • A 3.37% reduction in blood pressure,
  • Heart rate decreased by 6%,
  • Glutathione peroxidase levels increased by 7.15%, which is also a very important part of our body's antioxidant system.

In conclusion, vitamin C supplementation helped to reduce the damage caused by air pollution and improved markers in the trial participants.

How does Vitamin C protect from air pollution?

When inhaled, the small particles that enter the air from exhaust fumes, smoking, or other sources trigger various inflammatory processes in the body. These increase the production of the aforementioned inflammatory molecules and oxidative stress, which over time, can damage the vascular wall and other tissues. This is where vitamin C comes in, which protects against these negative processes through its antioxidant effects.

As there is little we can do individually to counteract air pollution, it is good to be aware of ways to protect ourselves against it. Vitamin C supplementation can be a practical solution, but high blood levels are important to achieve the desired effect.

In this study, 4x 500 mg per day was needed to see positive changes, which is much higher than the officially recommended amount.

Ren J, Liang J, Wang J, Yin B, Zhang F, Li X, Zhu S, Tian H, Cui Q, Song J, Liu G, Ling W, Ma Y. Vascular benefits of vitamin C supplementation against fine particulate air pollution in healthy adults: A double-blind randomised crossover trial. Ecotoxicol Environ Saf. 2022 Aug;241:113735. doi: 10.1016/j.ecoenv.2022.113735. Epub 2022 Jun 8. PMID: 35689890.

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