Life Extension Magazine®
According to researchers from the Massachusetts Institute of Technology, air pollution is responsible for as many as 200,000 premature deaths every year in the US alone.1
Air pollution has become a serious global health epidemic. About 80% of people live in areas of the world where air pollution exceeds the World Health Organization’s air-quality guidelines.2 This exposure is associated with higher rates of cardiovascular and respiratory illnesses and death.3,4
New studies link pollution to glucose intolerance,5 along with asthmatic mothers delivering preterm babies,6 and damage to blood vessels in individuals as young as 23!7
While we can’t avoid all air pollution, we can help protect ourselves from its damaging effects. Researchers have identified specific nutrients that can inhibit some of the effects of pollutants—and even help remove them from the body.
High-Risk Pollutants
We are barraged with toxic compounds from industrial facilities, agricultural runoff, chemicals used on military bases, pesticide-laced foods, and emissions from trucks, cars, and planes.
Over 80,000 chemicals have been synthesized over the last 70 years—many of which are known carcinogens—and more than 4 billion pounds of these chemicals are released into the environment every year.8-11 The vast majority have never been adequately tested by the Environmental Protection Agency (EPA) or any other government agency to evaluate their human health effects.12
In 2009, the Centers for Disease Control and Prevention (CDC) investigated the burden of 212 industrial chemicals in US citizens’ bodies and found high levels of many common industrial chemicals, including polybrominated diphenyl ethers (PBDEs) and bisphenol A (BPA),13 a chemical known for negatively affecting reproduction.14
Perfluoroalkyl chemicals have been found to be present in more than 98% of people sampled,15 and one member of this chemical family—perfluorooctanoic acid (PFOA), best known for being part of the substance TeflonTM—is linked with diseases ranging from kidney disease to cancer.16-19
Among the most commonly studied air pollutants are fine particulates, which are high-risk particles often measured as PM2.5 (indicating particles less than 2.5 microns in diameter). But even larger particles known as PM10 can travel deep into the body—through the bronchioles of the lung to the alveoli and even into the bloodstream, seriously damaging critical body functions.20-22 (For perspective, a human hair is about 70 microns in diameter.20)
Chronic exposure to pollution is linked to some of the most insidious diseases of our time. These include:
- Cardiovascular and respiratory diseases,3,4,7,20-22
- Glucose intolerance,5
- Premature births (among asthmatic mothers),6
- Ulcerative colitis,16
- Kidney disease,17
- Thyroid disease,18
- Decreased heart rate variability,23
- Impaired lung function,24,25
- Lung and other cancers,19,26,27
- Impaired cognitive function,28
- Asthma exacerbations,29 and
- Increased mortality30 and reduced life expectancy.31-33
How Pollution Damages Human Tissues
Scientists have found three main ways in which pollutants negatively impact our bodies.
First, fine particulates alter the autonomic nervous system,21,34 which is part of the peripheral nervous system and a regulator of cardiac function, among other functions. The resulting nervous system dysfunction leads to an abnormal decrease in heart rate variability. This means there is less variation in the time intervals between heartbeats, a condition that is associated with increased cardiac mortality.34
Second, environmental pollutants cause the overproduction of reactive oxygen and nitrogen species.35-37 When we inhale these tiny particles, they reduce antioxidant defenses in our respiratory tract, including glutathione and superoxide dismutase.38 If we don’t have enough of these protective substances, production of reactive oxygen species (ROS) is increased and oxidants can damage organic molecules. And of course, the damage caused by oxidative stress to cellular components contributes to a range of chronic diseases from cancer to aging.35
Air pollution also increases body-wide inflammation.5,39 Evidence shows that rising pollution corresponds to increased blood levels of cytokines, which are chemical messengers.7
Fortunately, researchers have identified several nutrients that are capable of interfering with these pollution pathways. This means that even though we can’t avoid exposure to ubiquitous environmental toxins, taking the proper nutrients can reduce our susceptibility to their damaging effects.
Let’s examine these nutrients individually.
What You Need to Know
Block the Devastating Effects of Pollution
- Globally, most people live in areas where air pollution exceeds World Health Organization air-quality guidelines.
- Chronic exposure to pollution boosts the risk of cardiovascular and respiratory morbidity and death, glucose intolerance, preterm deliveries, and endothelium damage.
- Certain remarkable nutrients have the capacity to block the destructive effects of pollution and, in some instances, even remove pollutants from the body.
- While it is impossible to avoid pollution, we can protect ourselves by supplementing with these protective nutrients.
Omega-3 Fatty Acids
One of the most damaging effects of pollution is its ability to increase oxidative stress in the body.35-37 Omega-3 fatty acids are able to help combat harmful oxidative stress by increasing the body’s protective defense systems.
Scientists studied an elderly population to determine if supplemental omega-3 polyunsaturated fatty acid (PUFA) from fish oil would have an impact on the oxidative response induced by exposure to PM2.5 pollution particles.40 They found that taking just 2 grams of fish oil daily for four months helped protect the body against oxidative stress. Specifically, it led to a 49% increase in superoxide dismutase (SOD) activity, a 62% increase in glutathione (GSH), and a 72% decrease in lipoperoxidation—all indicative of higher activity of endogenous antioxidants.40
In another study, healthy, middle-aged individuals took 3 grams of omega-3s from fish oil daily for three weeks and were then exposed to concentrated ambient fine and ultrafine particles. The researchers found that the omega-3s blocked the harmful cardiac and lipid effects induced by the particulate matter.41
B-Vitamins
Research shows that consuming adequate amounts of certain B vitamins can help prevent a potentially deadly impact of pollution: a decrease in heart rate variability.42
Researchers found that individuals with a lower dietary intake of folate, vitamin B6, and vitamin B12 showed significantly decreased heart rate variability 48 hours after an increase in ambient PM2.5 levels.42
However, in those with a high, daily dietary intake of these nutrients, negative effects of increased particulate pollution were prevented.42
Vitamins C and E
Vitamins C and E have been found to work together to help protect the body against oxidative stress caused by air pollution.
Researchers measured oxidative stress biomarkers in individuals exposed to coal-burning emissions from an electric-power plant before and after supplementation with 500 mg of vitamin C and 800 mg of vitamin E, which were then compared to nonexposed individuals (control). After six months, they again measured these biomarkers.43
Prior to supplementation, the individuals that were exposed to the polluted air experienced numerous breaches in their bodies’ defense systems. For example, they had decreased levels of some protective substances (including glutathione and vitamin E), and the activities of several antioxidant enzymes were impaired (including catalase, glutathione peroxidase, glutathione reductase, and glutathione s-transferase). In addition, markers for lipid and protein damage increased.43
After supplementing with vitamins C and E, markers for lipid and protein damage were decreased and antioxidant defenses were significantly improved to levels seen in the control group that was not exposed to pollution—indicating protection against air pollution-induced oxidative stress in the body.43
Some trials have also shown the benefits of using vitamins C and E in combination on asthma patients to help reduce ozone-associated lung-function decline44 and ozone-induced bronchial hyperresponsiveness.45
Vitamin D
Air pollution has a direct negative influence on vitamin D status because it interferes with the amount of ultraviolet-B (UVB) radiation that reaches ground level and human skin.
One study found that to attain the same blood levels of vitamin D from sun exposure as rural residents—as measured by 25-hydroxyvitamin D [25(OH)D] serum levels—residents of polluted urban areas would need two to three times the “sun exposure index.”46
In another study, children living in an area of Delhi affected by high levels of air pollution were shown to have mean serum 25(OH)D levels that were 54% lower than those in children living in less polluted areas of the same city.47 Similarly, women living in the polluted Iranian city of Tehran were shown to have lower vitamin D levels than women living in Ghazvinian, a less-polluted city in Iran.48
Since any amount of sun exposure damages skin DNA, it’s better to obtain vitamin D in low-cost supplement form.
Cruciferous Compounds
Studies have found that both broccoli extract and the broccoli compound sulforaphane work in numerous ways to protect the body against the harmful effects of air pollution.
Breathing in polluted air can be especially damaging to the respiratory system, leading to oxidative stress that can set the stage for asthma and other airway diseases. One important study found that sulforaphane can induce the gene expression of enzymes that help combat oxidative stress in the upper airway.49 As a result, the researchers concluded that sulforaphane could be a “novel therapeutic strategy” for oxidant-induced airway disease. Along those same lines, broccoli sprout extracts containing a sulforaphane precursor have also been found to reduce the nasal allergic response to diesel exhaust particles.50
Broccoli sprouts have also been found to rapidly—and sustainably—detox the body of airborne pollutants. It works by promoting the rapid excretion from the body of carcinogenic air pollutants (including benzene).51 This is especially important since exposure to air pollution has been linked to lung cancer and cardiopulmonary diseases.
A component in Brussels sprouts, called glucosinolates, can reduce the oxidative DNA damage caused by environmental toxins by up to 28%.52 They reduce the carcinogenicity of many environmental toxins by boosting the genetic expression of important detoxifying enzymes.53,54
Finally, watercress, a lesser-known cruciferous vegetable, contains a derivative of glucosinolate that has been found to protect against DNA damage,55,56 making watercress extract protective against high-risk environmental carcinogens, such as those found in tobacco smoke.57-59
Olive Oil
Research conducted by the United States Environmental Protection Agency demonstrated that olive oil consumption prevented reduction in blood vessel dilation due to pollution.60
For the study, scientists gave 42 subjects 3 grams of either olive oil or fish oil every day for one month, and a third group served as controls. Participants were then exposed to two hours of filtered air to determine a baseline, and the next day they were exposed to two hours of fine and ultrafine concentrated ambient particulate matter (a dangerous component of air pollution). Next, the researchers tested the subjects’ endothelial function by measuring their flow-mediated dilation of the brachial artery and their fibrinolysis, the body’s natural anti-clotting mechanism.
They found that flow-mediated dilation was reduced in the control group and, to a lesser extent, in the fish oil group as well. However, the olive oil group showed no statistically significant reduction in dilation, which means they were protected against the effects of the polluted air on their blood vessels’ ability to dilate.60
As an added benefit, beginning immediately after exposure to the polluted air and continuing for a full 20 hours, the olive oil group experienced elevated levels of plasminogen activator, a protein that breaks down clots. Olive oil also improved markers associated with both vasoconstriction of blood vessels and fibrinolysis.60
Based on fish oil’s beneficial properties that protect against the effects of pollution, it makes sense to include fish and olive oils in your diet and/or supplement program.
Chlorophyllin
Chlorophyllin delivers special protection against pollution through its novel ability to bind to toxins and excrete them from the body before they can induce mutations in DNA and trigger cancer.61-63
For example, one extremely dangerous environmental pollutant is DBP (dibenzo[a,l]pyrene), found in coal tar and cigarette smoke. It is one of the most potent environmental carcinogens known.64 In a fish study, scientists found that chlorophyllin was able to reduce the amount of DBP in the liver by up to 63%.65
The Premature Death Toll from an Isolated Jump in Pollution
Underscoring the health risks of global air pollution is the increased mortality that can arise from an isolated source of pollution—as shown by the numbers in the Volkswagen emissions-cheat case.
In September 2015, the US Environmental Protection Agency discovered that the German automaker had developed and installed “defeat software” in 11 million of its diesel vehicles sold between 2008 and 2015. This software sensed when a car was undergoing an emissions test and would only then engage the vehicle’s full emissions-control system, which would otherwise be disabled. This cheat allowed vehicles to emit 10-40 times more emissions than legally permitted under the Clean Air Act.66
Multiplying that amount of excess pollution by the 2.6 million such vehicles sold in Germany alone—and extrapolating over the population of Europe—scientists at the Massachusetts Institute of Technology estimate that 1,200 Europeans will die prematurely as a result of this single pollution source, with 500 of them losing as much as a decade of life. Premature deaths will occur as far away from the German vehicles as the Czech Republic and Poland.67
The MIT scientists also predicted that if Volkswagen could somehow recall and fix all of the remaining cars to meet emissions limits by the end of 2017, it could save an additional 2,600 premature deaths across Europe.67
In the US, where far fewer of these vehicles were sold, deaths attributed to the emissions “cheat software” are still estimated to reach about 106.68
But the death toll estimates don’t include the nonfatal health effects that are spread over a much larger number of individuals. The nitrogen dioxide and ozone from tail pipes increase airway inflammation, asthma, bronchitis, wheezing, heart attacks, and chronic obstructive pulmonary disease, with older people at greater vulnerability.69
Even if it cannot be measured, air pollution affects the health of everyone to at least some extent.
A spokesman for Volkswagen pointed out that the firm’s current vehicles pump out dangerous pollutants at levels that are “comparable” to those of their competitors.67 In light of the four billion euros in additional health costs, the unnecessary years of ill health—and the early deaths of thousands of people—that just doesn’t seem very comforting.
Summary
Most people are chronically exposed to air pollution that exceeds WHO air-quality standards. Over time, this causes changes in the body that can lead to cardiovascular and respiratory disease, increased glucose intolerance, increased risk of preterm deliveries, and endothelium damage.
Scientists have identified certain nutrients that can inhibit the harmful effects of pollutants and even help remove them from the body.
This means that even though it is impossible to avoid environmental pollution, we can still protect ourselves from its harmful effects.
If you have any questions on the scientific content of this article, please call a Life Extension® Wellness Specialist at 1-866-864-3027.
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