The effects of pollution on the environment are well documented, but we tend to hear less about the damaging consequences of air pollution on physical health and cognition, and particularly on the ageing brain. That said, there have been some interesting studies on this topic published in recent years.
Unquestionably, high levels of air pollution can cause an increased risk of heart attacks, respiratory problems and eye and nasal irritation. Nitrogen dioxide levels alone contributes to the early deaths of 40,000 Brits every year. But what about low levels? And what can we do to look after ourselves?
In this blog, we’ll look more closely at the biological impact of air pollution and suggest means of countering such effects.
Ambient air pollution, the kind we contend with living in busy modern cities, is essentially toxic air. According to the World Health Organisation, it caused almost four million premature deaths in 2016, and over 90% of all children live in areas where pollution exceeds safety guidelines.
It should surprise no-one to learn that when fine particles found in polluted air (soot, dust, sulfates etc) enter the lungs and cardiovascular system, poor health outcomes happen. If pollution is destroying our environment, indeed destroying our planet, why should we expect our fragile human bodies to be immune?
Air pollution has been linked with a number of diseases including heart disease, asthma, stroke, dementia, diabetes, lung cancer and chronic obstructive pulmonary disease.
Indeed, WHO figures suggest air pollution causes 29% of global lung cancer deaths, 43% of COPD deaths and a quarter of ischaemic heart disease deaths. It can also increase the risk of premature birth.
Research published in late 2018 indicates that air pollution causes changes to the heart similar to those in the early stages of heart failure. What was especially troubling about this finding was that heart changes occurred even to people exposed to low levels of air pollution (i.e. below UK guidelines).
In essence, a correlation was found between pollution levels and enlarged ventricles of the heart, the same changes as would be witnessed in sedentary people or those with high blood pressure.
Another study appeared in the peer-reviewed journal Respiratory Research in 2018, looking specifically at pollution and respiratory disease. A wide number of pollutants were covered by the study, not least nitrogen dioxide (NO2), ozone (O3), particulate matter and phthalates.
Researchers “assessed the evidence for alterations in diet, including vitamin supplementation in abrogating the effects of pollution on asthma and other chronic respiratory diseases” and found “evidence to suggest that carotenoids, vitamin D and vitamin E help protect against pollution damage which can trigger asthma, COPD and lung cancer initiation,” adding that “vitamin C, curcumin, choline and omega-3 fatty acids may also play a role.”
Does air pollution affect cognitive performance? Research certainly suggests that it does. One Chinese study showed that long-term exposure “impedes cognitive performance in verbal and math tests,” with the effect becoming more pronounced as people age, especially for men and the less educated. One author in the study speculated that air pollution damaged white matter in the brain, a composition associated with language ability.
There are many pathways by which pollution may reach the brain, including via nasal passages and the bloodstream.
The best way to limit the deleterious effects of pollution on the human body is to avoid inhaling such pollution at all. Unless you live in the wilderness, that is easier said than done. However, there are steps we can take:
1. Avoid pollution ‘hotspots’ such as busy road junctions
2. Use quieter streets and side roads, which are cleaner due to less traffic
3. If in a vehicle, keep the windows shut and recycle the air
4. Consider using a personal medical device such as a lung-protecting inhaler or pollutant-reducing air purifier
5. Reduce outdoor physical exertion if you live in an area of high pollution
6. Use an air pollution app to get real-time updates of air pollution levels in your area
7. Cover your baby’s pram (they are physically closer to vehicle exhaust pipes and therefore more vulnerable)
8. When ascending a hill, keep to the side where traffic flows downward, away from the majority of the fumes
9. Ensure proper home ventilation
As evidenced by the results of the aforementioned study in Respiratory Research, dietary choices appear to counteract the ravages of pollution.
10. Ensure adequate omega-3 intake
Omega-3s in particular seem to be powerful allies in our battle against pollution. In one 2012 study conducted by the Environmental Protection Agency, 29 middle-aged subjects were given either fish oil or olive oil daily for a month, then exposed to two hours of particulate pollution. While the olive oil group experienced elevated LDL cholesterol and triglycerides, not to mention a decline in heart rate variability, the fish oil group did not suffer these worrisome cardiac effects.
“Our findings suggest that omega-3 fatty acid supplements offer protection against the adverse cardiac and lipid effects associated with air pollution exposure,” concluded researchers.
This isn’t the only study which touts omega-3’s anti-pollution effect. A widely-reported 2017 mice study showed that omega-3s could both prevent and treat the inflammation and oxidative stress caused by fine particle exposure, delivering a 30-50% reduction in harm.
Researchers believed the protective effect was attributable to omega-3’s famous anti-inflammatory properties. They also suggested that omega-3s might “reduce fine particle-induced inflammation through minimising the penetration of fine particles from the lungs into other organs,” although they admitted that more investigation was needed.
Four grams per day is the equivalent human dose to that given to the study’s mice subjects; this can be obtained via seafood or a high-quality, high-strength fish oil supplement.
Lead researcher Dr Jing Kang was unequivocal in his endorsement: “I would definitely recommend taking Omega Fatty Acids to counter air pollution problems.”
11. Top up your vitamin D
There seems to be a relationship between vitamin D status and local pollution levels: although only evaluated in a few studies, those living in areas of higher pollution appear to have a higher propensity for vitamin D deficiency.
This may be at least partly due to the fact that people living in heavily polluted areas tend to spend less time outdoors. In this sense, there is a greater need to maintain healthy vitamin D levels if you are so affected.
However, vitamin D may also have a protective effect given that it helps the body maintain a healthy inflammatory and immune response. Although more research is needed, the link between pollution and vitamin D deficiency compels us to recommend supplementation for those concerned.
You can obtain 1280mg of omega-3 fish oil, plus 1,000 IU of vitamin D3, from a single UnoCardio 1000 softgel capsule. The supplement is currently ranked #1 for quality by independent laboratory, Labdoor.
12. Eat broccoli or use a greens powder containing broccoli sprouts
Broccoli sprouts may also help to reduce the harmful biological effects of air pollution. In a study from the University of California, Los Angeles, drinking broccoli sprout extract for four days suppressed nasal inflammatory response after exposure to diesel exhaust pollution.
The broccoli sprout extract was rich in a sulforaphane precursor, glucoraphanin, which is also found in cauliflower and mustard. Researchers noted that eating 100-200g of broccoli would be equivalent to the extract used in the study, and would thus provide the same preventive and therapeutic potential to reduce the impact of particulate pollution.
One food supplement which contains an appreciable broccoli sprout content is pHresh Greens.
13. Ensure adequate Vitamin E and C
According to a 2002 study, supplementation with antioxidant vitamin C and vitamin E may modulate the impact of ozone exposure on the lung function of children with moderate to severe asthma.
As both nutrients were cited in the 2018 Respiratory Research paper, it seems that ensuring a proper intake would be a good idea if your goal is to lessen the impact of pollution on the body. The dosages used in the 2002 study, incidentally, were 50 mg/day of vitamin E and 250 mg/day of vitamin C. You can obtain such dosages from foods and/or supplements.
There should be no doubt: pollution can cause and exacerbate a variety of chronic diseases, and the World Health Organisation is entirely right to dub air pollution the planet’s single largest environmental health risk factor.
That being said, there are many lifestyle and dietary interventions you can make to limit your exposure and increase your body’s innate immune defences and capacity for detoxification.
Be sure to eat a diet rich in carotenoids (plenty of carrots, leafy greens and tomatoes), omega-3 and anti-inflammatory turmeric, and take care to get plenty of vitamins and antioxidants; don’t needlessly exposure yourself to pollution, for example, by making your daily exercise a brisk run alongside a busy road during rush hour!
Follow these simple tips and you will certainly minimise the harmful impact of pollution. And if you’ve found this article valuable, please consider sharing by clicking on one of the social roundels beneath the article title at the top of this page.
Supplementation with antioxidant vitamin C and vitamin E may modulate the impact of ozone exposure on the lung function of children with moderate to severe asthma.