Is Air Pollution Changing our Gut Microbiota?

It may seem a far cry, but scientists have been studying the effects of particulate matter (PM) in our intestines, gut microbiota (previously referred to as gut flora) and its relation to the sharp increase of Inflammatory Bowel Diseases (IBD). There is not an overwhelming amount of research, but certainly for more than a decade institutes in several countries have researched the possible link between exposure to air pollutants and various parts of our digestive system.

These studies show why being careful about what we eat and drink can take us a long way in protecting our gut microbiota from air pollution. In fact, hereditary genes may explain only a fraction of the IBD and scientists have in the past two decades seen that environmental factors are important contributors to these diseases.

But how does PM reach our bowel/intestines?

Well, researchers have observed that there are two primary ways: first the lungs clear part of air pollutants through a process called ‘mucocialiary clearance’ towards the intestines; and second we ingest it through our water and food.

And what is the effect of PM in our bowel?

Scientists in this field suggest that air pollutants cause systemic inflammation and change of the intestinal microbiota. Research has shown correlation between air pollution and IBD but scientists call for caution in the interpretation of these results due to methodological weaknesses and suggest more research should be done. However,

“If this connection is found to be true, this could have important implications for public health since intestinal diseases are relatively common and cause significant morbidity and mortality in addition to their economic impacts. Understanding how pollution contributes to intestinal disease will identify potential interventions or help advocate for patients by reducing exposures to dangerous materials.” say Leigh A. Beamish, Alvaro R. Osornio-Vargas and Eytan Wine in their 2011 publication in the Journal of Crohns and Colitis.

More recently (2015), scientists from Canada published an article on how microbiota can be modified by air pollution and last moth a group of researchers also published an article on PM and its effect on gut microbiota and the link to cholesterol. Overall, there is increasing knowledge of the importance of maintaining a healthy gut microbiota as a protection against diabetes, obesity, metabolic disorders and IBD. Scientists have shown that air pollution affects both the composition and the function of microbiota. They concluded:

“Together, our study in IL-10−/− mice, in conjunction with previous experimental and epidemiological observations, strongly suggests that ingested particulate matter could trigger and accelerate the development of gastrointestinal inflammatory diseases” Salim, Kaplan and Madsen from the University of Alberta and Calgary.

As individuals, let’s start now to protect ourselves. We can eat organic, we can have a specific vegetable and fruit cleansing routine, we can filter our water. Let’s start minimizing our ingested air pollution to take care of our gut microbiota!


NIH – Air pollution effects on the gut microbiota: a link between exposure and inflammatory disease

Nature – Ambient Ultrafine Particle Ingestion Alters Gut Microbiota in Association with Increased Atherogenic Lipid Metabolites

Trying to sleep but you cannot?

Sleep is not the first thought we have when thinking about the effects of air pollution.

A study conducted by Dr. Martha E. Billings, assistant professor of medicine at the University of Washington was presented in May at the American Thoracic Society International Conference. The study shows that air pollution affects sleep quality.

“Prior studies have shown that air pollution impacts heart health and affects breathing and lung function, but less is known about whether air pollution affects sleep,” said lead author Martha E. Billings “We thought an effect was likely given that air pollution causes upper airway irritation, swelling and congestion, and may also affect the central nervous system and brain areas that control breathing patterns and sleep.”

The study conducted showed that both PM2.5 and nitrogen dioxide are linked with poor sleep quality. The higher PM2.5 concentration leads to 50% odds of having poor sleep. Similarly, high levels of nitrogen dioxide increased by 60% the chances of experiencing poor sleep. 

Exactly why, is yet to be studied, but air pollution irritates nose, sinuses and back of throat which affects breathing and ultimately may have an impact on sleep quality. Also, air pollutants can enter the blood and can potentially have an effect on the brain and its breathing regulation capacities, therefore disrupting sleep.

“These new findings indicate the possibility that commonly experienced levels of air pollution not only affect heart and lung disease, but also sleep quality. Improving air quality may be one way to enhance sleep health and perhaps reduce health disparities,” Dr. Billings said

Sleep problems are common everywhere and on the increase. The use of multiple aids to sleep is increasing. This study shows how important it is to look at our environment, know the quality of our indoor and outdoor air and take measures to improve it. Improving air quality in our indoor space may go a long way in helping us having better sleep quality!

Monitor air quality!

Neuroscience News
AMERICAN THORACIC SOCIETY – Air Pollution May Disrupt Sleep
Newsweek – Trouble Sleeping? Air Pollution May Be to Blame, Study Says
The Guardian – Air pollution linked to poor sleep, study finds

Crazy for a cruise holiday? Let’s talk air quality

A cruise is one of the most sought-after holiday destinations. The Caribbean, Mediterranean, Alaska, northern Europe and some areas in Asia have the largest array of Cruises with lavish restaurants and what seems like a relaxing holiday in the middle of nature but with all the conveniences of a touristy city on board. Worldwide a total of 24.2 million passengers enjoy cruises every year.

Unfortunately for cruise holiday goers, reports conducted by journalists in France and in the UK have shown that fine particulate matter (known as PM2.5 and PM 10) is particularly high on these cruise destinations.

Cruise ships are important sources of air pollution impacting the routes they cover and the cities in which they dock. One cruise ship emits the same amount of carbon dioxide as one million cars per day. We might think that this is only the trail left by the cruise, but in fact it affects also the people on the cruise. Journalists measured the air quality on the main deck and found that the concentration of fine particles was twice as high as the concentration in London’s Picadilly Circus and similar to the measurements in New Delhi, all coming from the same ship’s funnels.


Cruises use residual fuel of very low quality, it’s the fuel left after the refined fuel for cars has been extracted.  But it’s cheap and maritime global regulation is limited and difficult to enforce. Nonetheless, the International Maritime Organization has fixed  the 1st January 2020 as the date for all passenger ships to use fuel with maximum 0.5% lead content, it is now 3 times that level at 1.5%.

All cruise goers and communities living in the ports where these cruise ships dock have the right to know what they breathe. More regulation is essential, but constant monitoring on-board and off-board is essential to reassure users and communities of the air quality they are exposed to.

Meo’s air quality monitor- measures PM2.5 and PM10.

Let’s measure and take control of the air we breathe!

Independent – Air quality on cruise ship deck ‘worse than world’s most polluted cities’, investigation finds
LaProvence – Le souffle pollué des géants des mers en Méditerranée

When global problems affect your local air

In our day-to-day life we have all noticed that the morning after heavy rain it’s usually a clear and fresh morning with low levels of airborne pollution. Wind conditions usually blow pollution out of the cities and those peaks of harmful air are mostly in days with no air flow or precipitation.  Empirically we have experienced the fact that weather patterns have an effect on dissipating air pollution or not.

This past week, researchers from the Atmospheric Sciences, Georgia Institute of Technology –Atlanta, published a paper in Science Advances on the effects of arctic meltdown on air pollution in China. The research clearly shows the challenges faced by China to address its air quality problems. Until now, most critics have focused on the need for China to control its emissions and to strike a healthier balance between development and environment degradation. Authorities in China have an increasing interest in controlling air quality, have implemented emission caps and most importantly are now the country with the largest production of clean energy. However, air quality is far from improved and pollution has not decreased as was hoped. The relevance of this research is that it affirms, following weather modelling analysis, that in the Eastern Plains of China, emissions’ control is important but is not enough to improve air quality. In fact, major global climate change problems are playing a significant role in promoting the accumulation of air pollution in this region.

“The ventilation is getting worse,” said study author Yuhang Wang, an atmospheric scientist at Georgia Institute of Technology in Atlanta to The Guardian “We think climate change, as it is driving rapid warming of the Arctic, is having a large effect on pollution in China.” “The very rapid change in polar warming is really having a large impact on China, emissions in China have been decreasing over the last four years, but the severe winter haze is not getting better. Mostly that’s because of a very rapid change in the high polar regions where sea ice is melting and snowfall is increasing,” he said. “This keeps cold air from getting into the eastern parts of China, where it would flush out air pollution.”

This is a scientific example of how weather conditions affect the build-up of air pollution in a certain place. This helps us further connect the dots between the bad air quality that harms our health and global problems such as green-house gas emissions, climate change and melting of the Arctic sea ice.Emissions of greenhouse gases from human activity cause between half to two-thirds of the fall in summer ice. Scientists predict that if the Arctic sea ice melting continues along with a correspondent increase in Eurasian snowfall, extremely poor ventilation conditions will occur and air quality control will prove increasingly challenging to implement unless greenhouse gas emissions are reduced not only in China but globally. The National Snow and Ice Data Center (NSIDC) reported in February 2017 that: “Antarctic sea ice is nearing its annual minimum extent and continues to track at record low levels for this time of year. On February 13, Antarctic sea ice extent dropped to 2.29 million square kilometers (884,000 square miles), setting a record lowest extent in the satellite era.”  

Air pollution affects us ALL and is one more environmental problem that is made worse by climate change!

The Guardian – ‘Airpocalypse’ smog events in China linked to melting ice cap, research reveals
Science advances – Arctic sea ice, Eurasia snow, and extreme winter haze in China
Science – Why is China’s smog so bad? Researchers point far away to a melting Arctic


Strokes and What We Breathe

When we think about the health effects of air pollution, our immediate thought goes to our lungs. But the silent threat of poor air quality reaches many unexpected areas of our body. In the past two decades, research has shown that strokes, heart attacks and irregular heart rhythms can result from exposure to air pollution especially among people at risk. Currently, nearly 15 million people suffer a stroke worldwide, out of which 6 million die and 5 million are left with disabilities, possibly severe. The latest study suggests that approximately 29.2% of global strokes are linked to air pollution and the strongest link (33.7%) was seen in developing countries were solid fuels are burned indoors for energy. In developed countries, the link is much weaker at 10.2%.

“A striking finding of our study is the unexpectedly high proportion of stroke burden attributable to environmental air pollution, especially in developing countries. Air pollution is not just a problem in big cities, but is also a global problem. With the ceaseless air streams across oceans and continents, what happens in Beijing matters in Berlin. Air pollution is one aspect of the fossil fuel and global warming problem, which is itself partly a result of westernisation and urbanisation, especially in India and China.” Professor Vladimir Hachinski, University of Western Ontario, London, Canada and Dr Mahmoud Reza Azarpazhooh, Mashhad University of Medical Sciences, Mashhad, Iran.

Asia is responsible for two-thirds of the global stroke mortality. The local situation is characterised by two distinct yet opposite trends 1. mortality following a stroke has been declining in North Asia (Korea, Japan, Taiwan and urban China) perhaps due to improved stroke care, albeit the occurrence (incidence) of stroke is apparently not declining, thus leaving a greater number of people with long-term care needs, and 2. southern Asia (India, Pakistan, Bangladesh, Indonesia) where life expectancy is increasing but risk factors such as hypertension, diabetes, obesity, cigarette smoking are not yet adequately addressed. Given that cardio-vascular diseases are particularly affected by small particles found in haze, smoke and dust and the high link found between strokes and pollution, air pollution may be playing a major role in stroke statistics in Asia.

Effects of air pollution in cardiovascular diseases and strokes may be immediate or long-term. Immediate effects happen in older persons and sensitive persons with the build-up of fatty deposits in the arteries, where accumulation of small particles may worsen the situation.[7] Long-term exposure to poor air quality may, according to research, facilitate and worsen atherosclerosis (hardening and narrowing of the arteries) a disease commonly associated with high blood pressure and heart attacks / strokes.

In conclusion, if you are a person at risk of cardiovascular diseases or not “The central theme here is to be careful,” said Dr Luepker from the American Heart Association and “Avoid situations where you are exposed to a high level of air pollution.”


Circulation – Air pollution, Climate and Heart Disease
Science Daily – For the first time, air pollution emerges as a leading risk factor for stroke worldwide
BMJ – Stroke in Asia: geographical variations and temporal trends
NIH – Stroke in Asia: a global disaster

ASTHMATIC? Air pollution might be making it worse

Today, 235 million people across the world suffer from asthma. Indoor and outdoor pollution can trigger asthma attacks and make symptoms worse.

It is well documented that air pollution can trigger asthmatic reactions in people who are already diagnosed with asthma. The role of air pollution in people developing asthma is less understood. Nonetheless, research funded by the US Air Resources Board has shown that children living in communities with higher ozone levels and/or living closer to busy roads are more likely to develop asthma.

 Asthma: a chronic disease of the lungs. The airways narrow, swell and produce more mucus. Which makes breathing difficult and trigger coughing, wheezing and shortness of breath.

Asthma is rarely fatal but causes sleepless nights, fatigue, reduced physical capacity as well as school and work absenteeism. The use of medication is important, but management of asthma triggers is essential to deal with this chronic disease and to enjoy a good quality of life and overcome the economic burden.

Indoor and outdoor air pollution can trigger asthma attacks and make symptoms worse because air pollution irritates the lungs and airways. Exposure to long-term air pollution in high concentrations can trigger asthma in both children and adults. A research study showed that people with moderate to severe asthma were 40% more likely to have an acute asthma episode on high pollution days. Moreover, research suggests that if your exposure happens during pregnancy your baby could be more likely to develop asthma because particulates can cross through the placenta to the developing baby. According to the US Center for Disease Control (CDC) asthma is primarily affected by ozone (smog) and particle pollution (haze, dust or smoke).

Ozone is a gas and contributes to ‘smog’, mostly present in urban areas where there are more cars and in the summer when sunlight increases. Ozone triggers asthma, it irritates the lungs and airways and reduces their function making it more difficult for a person to breathe deeply. It has been directly related to increased asthma attacks, increased asthma related emergencies and increased need for asthma treatment. Small particles are emitted into the air from industrial activity and energy production and can reduce lung function and increase asthma attacks. Moreover, 60% of people with asthma have allergic asthma, which means that allergens such as dust, pollen and pets can  trigger inflammation of the airways and create an asthma attack. As a result of increased exposure to pollution, your airways can be more sensitive to allergens.

In Asia, it is estimated that less than 5% of adults suffer from asthma; and data about elderly asthma is not homogenous across the region, it ranges between 1.3 and 15.3% (5). A recent literature review on this subject showed that asthma was increasing with age in Asia, particularly in Korea, Japan, China, Hong Kong, Mongolia, Iran, India and Bangladesh.

Controlling asthma as well as the triggers that cause it to arise or get worse is important to lead a good quality life and also to reduce its economic burden. Asthma has direct costs in inhalers and medications and has indirect costs from the negative impact of productivity which can be as large as the direct costs. In addition, research showed asthma affects not only work absenteeism but also “presenteeism” (individual loss of function when at work). A study in the US in 2007 estimated that the total cost of asthma to society was USD 56 billion (USD3,259 per person). A separate research in Asia-Pacific estimated that indirect and direct costs ranged from USD184 in Vietnam to USD1,189 in Hong Kong.


Simple tips to know if air pollution is triggering your asthma attacks:

  • Keep a symptom diary and note daily activities and pollution levels. This will help you see patterns of symptoms linked to pollution levels.
  • When pollution is high and even 24h after you might notice:
    1. Increased sensitivity to other asthma triggers,  
    2. Symptoms are worse and harder to control,
    3. You are using your inhaler more.

Some tips on how to reduce asthma attacks triggered by pollution:

  • Know when and where pollution is bad and plan outdoor activities when or where pollution levels are lower.
  • Limit outside activities and outdoor physical exercise on high pollution days or in high pollution areas.
  • If you do go out, do it earlier in the day before pollution kicks in and stick to back streets, with less traffic.
  • Ensure your indoor air is clean and is not contaminated by outdoor air pollution. Avoid rush hours so that the quality of the air in your car can easily be controlled.
  • Avoid the smoke from barbecues and bonfires.
  • Note that the use of face masks may not make a difference to your asthma symptoms and can actually make breathing feel more difficult.


AsthmaUK – Air Pollution and Asthma

Asthma and Allergy Foundation of America – Air Pollution

NIH – Epidemiology of Adult Asthma in Asi

Air Pollution and Diabetes

The International Diabetes Federation says diabetes mellitus (common diabetes) affects around 400 million people across the world. Research in the past 10 years has shown that environmental irritants in the air and water play a role in these figures. A number of studies have now shown that air pollution has a synergy with other dominant factors and accelerates the propensity for type 2 diabetes, also known as adult-onset diabetes.

At The Duke University rats were exposed to air with highly polluted air (similar to Beijing readings) or filtered air for 19 days. The group of rats exposed to the Beijing air had 50% higher cholesterol level, 46% higher triglycerides and 97% higher total cholesterol.

What is happening in Asia?

Yes! Many studies have been conducted analysing this relation in humans. A study by the German Center for Diabetes Research (DZD) and the Helmholtz Zentrum München showed how air pollution at the place of residence increases the risk of developing pre-diabetic insulin resistance.

“Whether the disease becomes manifest and when this occurs is not only due to lifestyle or genetic factors, but also due to traffic-related air pollution,” said Professor Annette Peters, director of the Institute of Epidemiology II at Helmholtz Zentrum München and head of the research area of epidemiology of the DZD.

“The results revealed that people who already have an impaired glucose metabolism, so-called pre-diabetic individuals, are particularly vulnerable to the effects of air pollution,” said Dr. Kathrin Wolf, lead author of the study. “Thus, over the long term — especially for people with impaired glucose metabolism — air pollution is a risk factor for type 2 diabetes.”

Researchers from King Saudi University, Saudi Arabia, further acknowledged that traffic associated pollutants, NO2 (nitrogen dioxide), tobacco smoke and particulate matter have the strongest link with diabetes. And researchers from Naples University in Italy quantified the risk of future diabetes between 10 and 27% associated with exposure to just a 10 μg/m3 increase of PM2.5. In the most recent research, a US study looked at 1000 Mexican-Americans and found that PM2.5 exposure was significantly associated with diabetes risk factors, with an effect equivalent to that of obesity, the authors noted.

What is happening in Asia?

Asia is affected by the double burden of high levels of air pollution and a high percentage of the population with diabetes. In fact, Asian countries have 60% of the world’s diabetic population. China alone is leading this statistic with 10% of its population (98 million) affected by diabetes. This is the result of a combination of factors: socio-economic growth and industrialization; urbanization spreading widely and notable lifestyle changes. Moreover, Asians have genetically a higher predisposition for diabetes, they develop diabetes earlier and with lower body mass index and waist circumference when compared with the Western population. Prof Juliana Chan of the Chinese University of Hong Kong says there is a complex interplay between genetic, lifestyle and environmental factors, which have been compounded by China’s rapid modernisation. Worryingly, if we combine the higher predisposition to diabetes, the nearly 50% smoking rate among adult men, the change of diet due to globalization and the very high air pollution levels, we can understand the extent of the risk in Asia.

What can we do about it?

Reduce the effect of air pollutants on your diabetes risk:

  • Avoid smoking or passive smoking;
  • Know your indoor air quality and control it;
  • Protect yourself when exposed to outdoor air, especially when its highly polluted;
  • Adopt a healthy diet; and
  • Increase your level of physical activity.


Diabetes Journal – Air Pollution and Type 2 Diabetes

Science Daily – Air pollution, a risk factor for diabetes

NIH -Effect of environmental air pollution on type 2 diabetes mellitus

NIH – Particulate matter pollutants and risk of type 2 diabetes: a time for concern?

REUTERS – Air pollution not just bad for your lungs

TIME – Study: Air Pollution Heightens Risk of Obesity and Diabetes

Let’s help our body fight pollution: 4 nutrients not to miss!

Worried about air pollution? Wondering what else could be done? Today’s tip is on optimal nutrition to help your body fight air pollution. Research has shown that the health effects of air pollution are caused because the body has an inflammatory response that overtime degenerates into disease.

“Recent research has highlighted the potential of targeted nutrition to combat the decreased antioxidant capability, respiratory inflammation and neurological symptoms associated with certain pollutants.” explains Dr Daniel Raederstorff, principal scientist, DSM.

Infact good nutrition is the key to empower our body to moderate that inflammatory response. There are a number of studies that pinpoint micronutrients that increase protection from air pollution through increasing antioxidant functions and reducing inflammatory reactions. These are Vitamin C and E, Beta-Carotene and Omega 3. In addition, studies have found specifically that persons with low B6 and B12 have higher susceptibility to the effects of air pollution.

“Nowdays diets are characterized by an increasing intake of prepackaged foods. This dietary pattern results in a nutrient profile that is low in beneficial nutrients, such as antioxidants and omega-3 polyunsaturated fatty acids (PUFAs),” agrees Professor Lisa Wood, Centre for Asthma and Respiratory Diseases, University of Newcastle, Australia.

“As these nutrients protect against inflammation, populations are thus more susceptible to the damaging effects of pollutants, which can trigger chronic diseases such as asthma. Increasing the intake of antioxidants and PUFAs may reduce inflammation, providing opportunities for asthma management.”

What should I eat to help my body fight air pollution?

VITAMIN E- an antioxidant that helps protect against injuries in organs and can be found in dark leafy greens, nuts, seeds, avocados, shellfish, fish, plant oils, broccoli, squash, avocado and fruits. Research at King’s College, London, has shown that people suffering from lung diseases have decreased levels of vitamin E.

VITAMIN C- is a powerful anti-oxidant that can be found in citrus fruits, bell peppers, broccoli, berries, tomatoes, dark leafy greens, kiwifruit, guava, peas and papaya.

Beta Carotene- an antioxidant found in carrots, spinach, lettuce, tomatoes, sweet potatoes, broccoli, cantaloupe, and winter squash.

Omega 3 (polyunsaturated fatty acids (PUFAs)- omega-3 fatty acids reduce inflammation. Flaxseed oil, fish oil, chia seeds, walnuts, fish roe (eggs), fatty fish, seafood, soybeans, and spinach. Many of which are also rich in Vitamin B6 and/or B12.

Other foods commonly recommended are spirulina, cilantro and chlorella.

Start now and boost your body’s anti-inflammatory and antioxidant capacity!


DSM – Talking Nutrition