Better nutrition can play a role in tackling the detrimental cardiovascular effects that people suffer from having been exposed to polluted air. André Rhoen says optimizing micronutrients intake can help reduce inflammation, and therefore reduce the risk of developing chronic diseases.
The World Health Organisation (WHO) has identified cardiovascular diseases (CVDs) as the world’s leading cause of mortality. Nearly one in three people worldwide are affected by CVDs each year and more than three-quarters of these cases occur in low-income and middle-income countries, many of which are within Asia. CVDs accounted for 9.3 million deaths in this region in 2014; a significant figure which shows no sign of falling. Rapid urbanisation and economic growth in many developing Asian nations continue to charge a growing preference for processed food and sedentary lifestyles – both of which are factors driving increased CVDs.
But alongside personal health and lifestyle factors such as diet and exercise, scientific evidence also shows air pollution to have a marked and negative impact on cardiovascular health and other serious health complications.
Inhaling polluted air, especially air containing particulate matter of a diameter smaller than 2.5 μm (PM2.5), has a proven impact on the quality and duration of human life. Both short- and long-term exposure to air pollutants are associated with increased respiratory afflictions and cardiovascular mortality, as well as higher risk of contracting several chronic diseases, including diabetes and cancer. The situation is so dire that the WHO has reported that around seven million people died in 2012 as a result of air pollution exposure – that is one in eight global deaths.
The Asia Pacific region is no stranger to air pollution. In recent years, the issue of haze has become a severe health hazard in several parts of Southeast Asia, accelerated as more land has been cleared to expand plantations for the lucrative palm oil trade. Researchers claim the haze crisis in 2015 may have caused more than 100,000 premature deaths in areas closest to the forest fires in Indonesia. Meanwhile further north, India now rivals China for the highest number of premature deaths caused by dangerous air particles, having registered an alarming increase in deaths of nearly 50 percent between 1990 and 2015.
Not just hot air
With most of the world’s population (80 per cent) living in regions that exceed the WHO’s air quality guidelines, air pollution is a serious global health concern, and one which is also expected to become a key focus of government regulation and environmental reform going forward.
The crux of the air pollution problem lies within exposure to PM2.5, a complex mixture of extremely small particles and liquid droplets which are mainly emitted when fossil fuels are combusted and include both organic and inorganic substances, such as sulphate, nitrates, ammonia, sodium chloride, carbon, mineral dust and water.
Since PM2.5 carries several toxic substances, it can trigger a series of responses locally and systematically when inhaled into the human body, including the exacerbation of asthma, chronic obstructive pulmonary disease (COPD), decreased lung function and increased risk of heart attacks. At the cellular and molecular levels, exposure to PM2.5 causes an increased inflammatory response and a decreased anti-oxidative capability normally responsible for counteracting free radicals. The consequent increase in free radicals then escalates cell damage, raising the changes of non-communicable diseases such as CVDs.
The effect of air pollution is particularly pronounced in sensitive populations such as people with diabetes or the elderly – both growing bodies of people in Asia Pacific. Exposure to PM2.5 for these people for a few days or even hours can trigger CVD-related deaths from heart attacks or strokes.
Controlling and reducing emissions at their source is clearly a first and important step towards CVD prevention, but remains very challenging to implement practically in many countries. This requires coordinated efforts and resources including education, innovative and affordable technology, legislation and law enforcement and, most importantly, time. In China for example, even the most aggressive plan to lower PM2.5 would only achieve a 25 per cent reduction by the end of this year. It is clear that a significant proportion of communities worldwide will remain exposed to levels of PM2.5 well above the WHO recommendations for the coming years.
This is where we need alternative – and supplementary – measures to fight the effects of exposure.
Fighting the cardiovascular effects of air pollution through improved nutrition
New science now suggests that nutrition-associated solutions, such as a diet with adequate micronutrients and fish oil (otherwise known as PUFA, or long-chain poly-unsaturated fatty acids), can also have a positive impact on tackling the detrimental cardiovascular effects of exposure to polluted air.
Asia’s growing fast food culture, in particular, has resulted in an increasingly nutrient-deficient profile which risks making the population here more susceptible to the damaging effects of air pollution and associated chronic health issues, especially CVDs.
Optimising the intake of micronutrients, antioxidants and omega-3 EPA and DHA can potentially reduce inflammation and hence reduce the risk of developing CVDs. Several scientific studies have highlighted that certain micro-nutrients, such as omega-3 EPA and DHA, B vitamins and vitamins C and E, may reduce oxidative stress. In addition, various combinations of micronutrients may prevent the impact of PM2.5 exposure on different aspects of health. For example, omega-3 EPA and DHA alone may reduce oxidative stress, improve heart function and heart rate variability (HRV) decline induced by PM2.5 exposure. Meanwhile, B vitamins may prevent the decline of HRV while vitamin E and C may also reduce PM2.5 induced oxidative stress.
Fish oil is another nutrient that may prevent HRV reduction associated with PM2.5. In a double-blind clinical trial involving 50 subjects over 60 years old, participants were randomised to receive 2g of fish oil or 2g of soy oil (the placebo) for a period of six months. Results show that for every 8 μg/m3 increase in PM2.5, the corresponding reduction of heart rate variability-high frequency (HRV-HF) before supplementation was 54 per cent. After five months of fish oil supplementation, the reduction was only 7 per cent. In other words, a 47 per cent reduction of HRV-HF was prevented by fish oil, compared to just 31 per cent by the placebo.
Likewise, vitamin E and omega-3 EPA and DHA may protect against PM2.5-induced oxidative stress in vascular endothelial cells (cells lining the entire blood circulatory system). In an in-vitro experiment in China, supported by DSM, it was found that vitamin E and omega-3 EPA and DHA may block the inflammation and oxidative stress caused by ambient PM2.5. This inflammatory response and oxidative stress can be associated with PM2.5-induced vascular endothelial dysfunction.
Collaboration is key
There is clear scientific evidence demonstrating the promising health benefits provided by desirable micronutrient and antioxidant intake to combat the global health threat of air pollution. To take this to the next stage and realise the opportunity for better nutrition to combat poor cardiovascular health from air pollution, there must be more investment in research on nutritional solutions but also greater collaboration between scientific communities, industry bodies and governments. This is especially pertinent – and unfortunately in some cases more difficult to do – in the more heavily polluted yet under developed Asian countries where, in some instances, unhealthy living environments are common-place.
The simplicity and affordability of nutritional supplementation should be understood as one viable solution to minimise the impact of air pollution. However, these findings should not reduce the responsibility of polluters to reduce their impact and become compliant with the WHO air quality guidelines, nor remove the urgency for authorities to legislate and enforce environmental protection policies and regulations.
About the Author
Human Nutrition & Health
DSM Asia Pacific
Recently appointed the Asia Pacific Regional Vice President for Human Nutrition & Health (HNH), André joined Royal DSM, a global life sciences company active in health, nutrition and materials, in 2001 and has held various positions in the Global Strategy & Acquisitions department, as well as the Intermediates and Nutrition businesses. Prior to DSM, he worked for Philips Electronics. André is based at DSM’s Asia Pacific headquarters in Singapore.