Air Pollution in India – Vitamins and Minerals May Help, Even if Govt Won’t Act

Air Pollution and AQI – Air Quality Index are the buzz words in Northern India, if not for full year, but for 3 to 4 winter months starting from October every year. A reported AQI exceeding 1,000 which is way beyond hazardous category, too has been reported / claimed for New Delhi, the capital of India for this Calendar Year 2025.

While New Delhi and North India gets all the flak for the alarming levels of air pollution, fact is – most of the major cities in India have AQI and PM 2.5 levels far exceeding safe limits and are way too high compared to even smaller, neighboring countries, thus denting global image of India, as an emerging super-power.

Does Air Pollution really affect Human Health and how severely. Well – a 2014 report by WHO pegged around 3.7 Million Premature deaths, because of ambient air pollution. The WHO showed that in urban areas which monitor air pollution levels, greater than 80% of people are exposed to levels of pollution which exceed WHO limits.

Effects of Air Pollution – What the Science Says

The lungs rely on filtered air through the nose (with cilia and mucus attempting to filter/trap unwanted particles) or unfiltered air via the mouth. Polluted air contributes to chronic obstructive pulmonary disease (COPD) prevalence and symptom onset. 

The idea that air pollution can cause exacerbations of pre-existing asthma is supported by an evidence base that has been accumulating for several decades, however it has more recently been suggested that air pollution might cause new-onset asthma as well.

In October 2013, a Working Group of invited experts from 11 countries met at the International Agency for Research on Cancer (IARC) in Lyon, France, to evaluate the carcinogenicity of outdoor air pollution. The Group unanimously classified outdoor air pollution and PM from outdoor air pollution as carcinogenic to humans (IARC Group 1) based on sufficient evidence of carcinogenicity in humans and experimental animals and strong mechanistic evidence. 

So not only respiratory tract issues including COPD, Asthma or exacerbation of existing respiratory issues, excessive and prolonged exposure to air pollution could lead to lung cancers as well. A study of 495 lung cancer patients in the Indian sub-continent found that incidence was higher among non-smokers. 

This shows that the focus within lung cancer prevention needs to move from anti-tobacco public health messaging, to wider national and international policies to clean up air we are forced to breath and our ‘elected representatives remain as shameless and indifferent as ever to this ‘burning’ issue.

Nutrient protection – can your diet and supplements help where Govt has failed

Oxidative stress plays an important role in the development of age-related diseases. Evidence increasingly suggests that poor diet, including clinical malnutrition may increase the risk for oxidative stress and chronic diseases. 

Nutrition is known to play a significant role in the prevention and management of these same chronic diseases and has been shown to modulate the toxicity of Persistent organic pollutants. One study has suggested that there may be increased susceptibility to NO₂ when someone is in a fasting state but it is not known if it is the same for other pollutants.

Oxidative stress, resulting from an imbalance between reactive oxidant species and antioxidants, can lead to tissue damage, airway inflammation with increased asthma severity and abnormal immune responses. 

Serum concentrations of antioxidants have been positively associated with FEV₁ in people with and without asthma. Role of Vitamin, mineral and botanical compounds, with and without antioxidant properties follows.

Vitamin A and carotenoids

Vitamin A contributes to key biological processes including growth, vision, epithelial differentiation, reproduction, and immune responses.

The two dietary sources of this vitamin are pre-formed vitamin A (retinol) and pro-vitamin A (carotenoids). Dietary intake of retinol comes from animal sources (eg, whole milk, liver, and eggs) and fortified foods. Orange and yellow fruits and vegetables (eg, carrots) are the main dietary sources of carotenoids, including α-carotene, β-carotene, lycopene and β-cryptoxanthins and they are known antioxidants.

Oxidative stress might exacerbate asthma by increasing the release of pro-inflammatory cytokines, which may lead to increased airway inflammation, and airway responsiveness. Vitamin A might improve prevention or treatment of asthma by downregulation of oxidative stress, or via direct effects on the immune system for example downregulation of T-helper (Th)2 (pro-allergic) immune responses. 

However, vitamin A also enhances protective Th2 immune responses (eg, interleukin (IL) 4 expression). Lycopene, (a carotenoid) supplementation was shown to reduce allergic airway inflammation. 

Self-reported dietary intake of vitamin A or its components (retinol and carotenoids) was inversely associated with asthma and asthma symptoms.

According to World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) Second Expert Report from 2007, foods rich in carotenoids may protect against lung cancer (strength graded as ‘probable’). 

Vitamin C and E

Observational studies have reported that low vitamin C and vitamin E intakes are associated with a higher prevalence of asthma. 

Exposure to Ozone / O₃ results in dose dependent depletion of antioxidants vitamin C and E in the skin. Antioxidant supplementation with vitamin C and E above the minimum dietary requirement led to attenuated nasal inflammation and partially restored antioxidant levels in asthmatic patients exposed to high levels of O₃. 

A meta-analysis of 24 observational studies in children and adults found lower dietary intake (but not serum level) of vitamin E was also significantly associated with increased asthma severity. 

A London based bidirectional case cross-over study looked at whether individual plasma antioxidant concentrations (uric acid and vitamins C, A, and E) and 10 antioxidant genes could modify the response to PM with respect to hospital admissions for COPD or asthma. Two hundred and thirty four admissions were recorded and the level of PM10 was noted 14 days before and after each event. 

Combined admission rates were related to a 10 μg/m increase in PM10. Serum vitamin C modified the effect of PM10 on asthma/COPD exacerbations. A similar (although weaker) influence was observed for low levels of uric acid and vitamin E, whereas vitamin A showed no effect modification.

Vitamin D

Vitamin D is key to the metabolism of calcium and phosphorus. In adults with Asthma, normal vitamin D levels correlated with improved asthma control and therefore supplementation may play a role in uncontrolled asthmatics with vitamin D deficiency.

A Cochrane database systematic review was undertaken on vitamin D and asthma. Meta-analysis of a modest number of trials in people with predominantly mild to moderate asthma suggests that vitamin D is likely to reduce both the risk of severe asthma exacerbation and healthcare use.

Curcumin

The phytochemical curcumin, from turmeric, has been found to be a potent anti-inflammatory agent, and has been studied in regards to its anti-tumour, antifungal and antioxidant properties.

Curcumin could potentially be used to prevent airway inflammation due to cadmium inhalation. An animal model investigated the effect of Cadmium (CdCl₂)-polluted drinking water (40 mg CdCl₂/L) on the level of tumour necrosis factor- alpha (TNF-α) and IL-6 and found a preventative action of curcumin against Cd toxicity.

Specifically in COPD, curcumin has been shown in animal models to have a beneficial effect in smooth muscle cells and improve the mean pulmonary artery pressure and right ventricular myocardial infarction (RVMI) through stimulating the suppressor of cytokine signaling (SOCS) -3/JAK2/STAT signaling pathways. 

In other patients, a population based study of 2,478 people found that people taking dietary curcumin through eating curry had better pulmonary function. The mean adjusted FEV₁ associated with curry intake was 9.2% higher among current smokers, 10.3% higher among past smokers, and 1.5% higher among non-smokers. 

N-acetylcysteine

N-acetylcysteine (NAC) supplementation has been shown to attenuate airway responsiveness by 42% in individuals with airway hyper-responsiveness following inhalation of diesel exhaust compared with filtered air and a pre-clinical study demonstrated N-acetyl-L-cysteine supplementation in smoke exposed rats showed antioxidant protective effects. 

A meta-analysis and systematic review found long-term NAC therapy may reduce risk of patients COPD exacerbation. An ex-vivo study found that NAC reduced COPD exacerbation induced by lipopolysaccharide (LPS). Supplementation of NAC, 600mg once a day and a 20 minute daily walk in addition to regular treatment improved quality of life in stable COPD patients. 

Omega-3 Fatty Acids

Omega-3 oils (or n-3 polyunsaturated fats-PUFAs) have received much attention due to their ability to reduce inflammation, and for its anti-coagulant properties, thus reducing risk of cardiovascular diseases. 

There are recent studies which use omega-3 oils to combat the effects of pollution. Animal models of fine particle matter pollution, demonstrated that omega-3 oils prevented and improve inflammation caused by these fine particles with a further pre-clinical study showing that omega-3 oils reduced the oxidative damage in the intestines after heavy metals ingestion.

A Mediterranean diet has long been suggested as the most ‘healthy’ diet to follow and its health benefits are largely attributed to the content of fibre, antioxidants, protein, and moderate amounts of fat-predominantly from mono-unsaturated (MUFA) and omega-3 PUFA. Airway inflammation during asthma may be modulated by dietary intake. Fruit, vegetables and their antioxidants may lower airway inflammation. Fruit and vegetable intake was inversely associated with IL-8 protein in nasal lavage of asthmatic children. The Mediterranean diet does offer some protection against the effects of tobacco smoke in smokers and passive smokers.

Choline

Choline is a lipotropic agent involved in several biological functions (eg, neurotransmitter production, signaling lipids, and components of structural membranes), and as a methyl group donor. 

Dietary sources of choline include meat, liver, eggs, poultry, fish and shellfish, peanuts, and cauliflower. Choline deficiency is associated with neurological disorders, cardiovascular diseases, and inflammation.

Intranasal or oral administration of choline has been shown to reduce the number of eosinophils and reactive oxidant species in bronchoalveolar lavage fluid in a murine model of allergic airway disease. 

In human studies, 76 asthma patients were recruited and treated with a choline supplement (1500 mg twice) or standard pharmacotherapy for 6 months in two groups. The patients were evaluated by clinical, immunologic and biochemical parameters. The treatment with choline showed significant reduction in symptom/drug score and improvement in FEV₁ compared to baseline or standard pharmacotherapy. Choline therapy significantly reduced IL-4, IL-5 and TNF-alpha level as compared to baseline or standard pharmacotherapy after 6 months (p<0.01). 

Conclusion

There is increasing evidence to suggest that carotenoids, vitamin D and vitamin E help protect against pollution damage which can trigger asthma, COPD and lung cancer initiation. 

Vitamin C, curcumin, choline and omega-3 fatty acids may also have a protective role. The Mediterranean diet appears to be of benefit to the airways, but there is no evidence of benefit in protecting against air pollution, except for tobacco smoke. 

Your health is in your own hands, so while you keep paying taxes and contribute towards ‘Developed India’ – focus on your own diet to try and withstand the excessive air pollution.