Vitamin C supplementation may help shield lungs from damage caused by air pollution, even at levels considered relatively safe, according to new research that challenges assumptions about ‘acceptable’ air quality.
Low levels of PM2.5 trigger lung inflammation and damage the cellular ‘powerhouses’ known as mitochondria. However, vitamin C appears to effectively counteract these harmful effects.
The study, which combined animal models and laboratory cell experiments, focused on PM2.5 levels comparable to those in cities with generally good air quality, such as Sydney. Researchers exposed mice to daily doses of pollution particles while some received vitamin C supplementation in their drinking water.
It was seen that mice given vitamin C showed significant protection against pollution-induced lung damage, with reduced inflammation and preserved mitochondrial function. The vitamin effectively prevented the accumulation of harmful reactive oxygen species (ROS) – unstable molecules that damage cells – and protected against mitochondrial loss.
Laboratory tests on human lung cells supported these findings. PM2.5 exposure increased susceptibility to oxidative stress and inflammatory responses but pre-treatment with vitamin C significantly mitigated these effects.
The study found that pollution caused immune cells to flood into mouse lungs and triggered inflammation. It also damaged the cells’ ability to maintain their energy-producing components, leading to a build-up of faulty cellular machinery and harmful stress.
Vitamin C worked in several ways to combat this damage. It neutralised harmful molecules, reduced the production of damaging substances and helped restore the body’s natural defences. It also protected the cells’ energy systems and prevented them from breaking down.
The researchers point out that the dosage used in mice translates to approximately 1.1 grams daily for an average adult – a level that aligns with common high-dose vitamin C supplements and remains within established safety limits of up to 2 grams per day.
The findings suggest vitamin C supplementation could serve as a preventive strategy for people regularly exposed to air pollution, particularly vulnerable populations.
Brian Oliver, a professor in the School of Life Sciences at UTS said: ‘For the first time we are providing hope for a low-cost preventative treatment to a global issue affecting hundreds of millions of people. We know now that there is no safe level of air pollution, which causes inflammation in the lungs and leads to myriad respiratory diseases and chronic illnesses, especially in the case of bush fires.’
However he advised people to speak to their doctor before increasing their vitamin C intake: ‘This study suggests that taking the highest permitted dose of Vitamin C for you would potentially help, but you would need to speak with your GP to make sure you’re taking the right kind of supplement at the right levels and don’t accidently overdose on something else included in an over-the-counter supplement.’
The full research can be read here.
Photo: Simon Hurry / unsplash
