The study has been conducted in the U.S. and the headline conclusion is that very high doses of vitamin B supplements may “completely offset” the damage caused by the types of very fine particulate matter found in polluted air. Such research is important given the association of polluted air and the adverse affect on human health.
Air pollution is the result of human activities which impact upon the environment. Pollution occurs when harmful substances, such as particulates and biological molecules, are introduced into Earth’s atmosphere. At a certain level pollution can cause diseases, allergies or death in humans; as well as causing harm to other living organisms and damaging food crops. With people, the main types of ill-health effects include respiratory infections, heart disease, chronic obstructive pulmonary disease, stroke and lung cancer. This is to the extent that the World Health Organization estimates that each year air pollution causes the premature death of some 7 million people worldwide.
Tackling air pollution ideally involves going to the source, such as switching out polluting power stations for clean energy alternatives. The new study takes a different path and looks at medical solutions for humans who live in areas with levels of air pollution above acceptable internationally agreed thresholds. This is based on the scientific understanding that presence of environmental factors in air pollution seems alter genes in the immune system (epigenetic changes) by switching them on or off; with air pollution this can inhibit our defences. The research has looked at ways to prevent defenses from being deactivated and B vitamins are seen as the means to do this.
The small study used a daily B vitamin supplement containing 2.5mg of folic acid, 50mg of vitamin B6, and 1mg of vitamin B12 on test subjects. The study found a four week B vitamin supplementation limited what is known as the PM2.5 effect by between 28-76 percent at ten gene locations. PM2.5 refers to fine particles with a diameter of 2.5 μm or less, and these are among the pollutants that have the most severe effects upon human health. The study was led by Dr. Jia Zhong from Harvard School of Public Health.
Dr. Zhiong told BBC Science: “We didn’t have different doses and the doses we used were quite high, higher than a normal pregnancy suggested intake. So it is quite high but at the same we did observe this protective effect.” While the results are interesting, the study is is notably small. In addition it only looks at one region. For these reasons a follow-up study is required, focusing on a more heavily polluted air such as some of the cities in China or Mexico.
The research is published in the journal Proceedings of the National Academy of Sciences, and the paper is titled “B vitamins attenuate the epigenetic effects of ambient fine particles in a pilot human intervention trial.”
