Combating Air Pollution Effects with Food

There is a food that offers the best of both worlds—significantly improving our ability to detox carcinogens like diesel fumes and decreasing inflammation in our airways—all while improving our respiratory defenses against infections.

Outdoor air pollution may be the ninth leading cause of death and disability in the world, responsible for millions of deaths from lung cancer, emphysema, heart disease, stroke, and respiratory infection. In the United States, living in a polluted city was associated with 16, 27, and 28 percent increases in total, cardiovascular, and lung cancer deaths, compared to living in a city with cleaner air. As well, living in a city with polluted air may lead to up to a 75 percent increase in the risk of a heart attack. “Additionally, the possibility of dying in a traffic jam is two and a half times greater in a polluted city.” No one wants to be living in a traffic jam, but it’s better than dying in one.

In addition to causing deaths, air pollution is also the cause of a number of health problems. It may not only exacerbate asthma but also increase the risk of developing asthma in the first place. These pollutants may trigger liver disease and even increase the risk of diabetes. Indeed, “even when atmospheric pollutants are within legally established limits, they can be harmful to health.” So, what can we do about it?

Paper after paper have described all the terrible things air pollution can do to us, but “most…failed to mention public policy. Therefore, while science is making great strides in demonstrating the harmful effects of atmospheric pollution on human health, public authorities are not using these data” to reduce emissions, as such measures might inconvenience the population “and, therefore, might not be politically acceptable.” We need better vehicle inspections, efficient public transport, bus lanes, bicycle lanes, and even urban tolls to help clean up the air, but, while we’re waiting for all of that, is there anything we can do to protect ourselves?

As I discuss in my video Best Food to Counter the Effects of Air Pollution, our body naturally has detoxifying enzymes, not only in our liver, but also lining our airways. Studies show that people born with less effective detox enzymes have an exaggerated allergic response to diesel exhaust, suggesting that these enzymes actively combat the inflammation caused by pollutants in the air. A significant part of the population has these substandard forms of the enzyme, but, either way, what can we do to boost the activity of whichever detoxification enzymes we do have?

One of my previous videos Prolonged Liver Function Enhancement from Broccoli investigated how broccoli can dramatically boost the activity of the detox enzymes in our liver, but what about our lungs? Researchers fed some smokers a large stalk of broccoli every day for ten days to see if it would affect the level of inflammation within their bodies. Why smokers? Smoking is so inflammatory that you can have elevated C-reactive protein (CRP) levels for up to 30 years after quitting, and that inflammation can start almost immediately after you start smoking, so it’s critical to never start in the first place. If you do, though, you can cut your level of that inflammation biomarker CRP nearly in half after just ten days eating a lot of broccoli. Broccoli appears to cut inflammation in nonsmokers as well, which may explain in part why eating more than two cups of broccoli, cabbage, cauliflower, kale, or other cruciferous veggies a day is associated with a 20 percent reduced risk of dying, compared to eating a third of a cup a day or less, as you can see at 3:41 in my video.

What about air pollution? We know that the cruciferous compound “is the most potent known inducer” of our detox enzymes, so most of the research has been on its ability to fight cancer. But, for the first time, researchers tried to see if it could combat the pro-inflammatory impact of pollutants, such as diesel exhaust. They put some human lung lining cells in a petri dish, and, as you can see at 4:11 in my video, the number of detox enzymes produced after dripping on some broccoli goodness skyrocketed. Yes, but we don’t inhale broccoli or snort it. We eat it. Can it still get into our lungs and help? Yes. After two days of broccoli sprout consumption, researchers took some cells out of the subjects’ noses and found up to 100 times more detox enzyme expression compared to eating a non-cruciferous vegetable, alfalfa sprouts. If only we could squirt some diesel exhaust up people’s noses. That’s just what some UCLA researchers did, at an amount equal to daily rush hour exposure on a Los Angeles freeway. Within six hours, the number of inflammatory cells in their nose shot up and continued to rise. But, in the group who had been getting a broccoli sprout extract, the inflammation went down and stayed down, as you can see at 4:58 in my video

Since the dose in those studies is equivalent to the consumption of one or two cups of broccoli, their study “demonstrates the potential preventive and therapeutic potential of broccoli or broccoli sprouts,” but if broccoli is so powerful at suppressing this inflammatory immune response, might it interfere with normal immune function? After all, the battle with viruses like influenza can happen in the nose. So what happens when some flu viruses are dripped into the nostrils of broccoli-sprout eaters compared with people consuming non-cruciferous alfalfa sprouts? After eating broccoli sprouts, we get the best of both worlds—less inflammation and an improved immune response. As you can see at 5:55 in my video, after eating alfalfa sprouts, there is a viral spike in their nose. After eating a package of broccoli sprouts every day, however, our body is able to keep the virus in check, potentially offering “a safe, low-cost strategy for reducing influenza risk among smokers and other at risk populations.”

So, better immune function, yet less inflammation, potentially reducing the impact of pollution on allergic disease and asthma, at least for an “enthusiastic broccoli consumer.” But what about cancer and detoxifying air pollutants throughout the rest of our body? We didn’t know, until now. Off to China, where “levels of outdoor air pollution…are among the highest in the world.” By day one, those getting broccoli sprouts were able to get rid of 60 percent more benzene from their bodies. “The key finding…was the observed rapid and highly durable elevation of the detoxification of… a known human carcinogen.” Now, this was using broccoli sprouts, which are highly concentrated, equivalent to about five cups of broccoli a day, so we don’t know how well more modest doses would work. But if they do, eating broccoli could “provide a frugal means to attenuate…the long-term health risks” of air pollution. More on air pollution here.

I’ve been reading about the terrible effects of air pollution for a long time and I am thrilled there’s something we can do other than uprooting our families and moving out to the countryside.

For more on cruciferocity, see my videos Lung Cancer Metastases and Broccoli and Breast Cancer Survival Vegetable.

There’s a secret to maximizing broccoli’s benefits. See Flashback Friday:Second Strategy to Cooking Broccoli.

For more on Cooking Greens: How to Cook Greens and Best Way to Cook Vegetables.

What about broccoli sprout pills? See Broccoli: Sprouts vs. Supplements.

Speaking of respiratory inflammation, what about dietary approaches to asthma? Learn more:

There are sources of indoor pollution, too. See Throw Household Products Off the Scent.

There is one way what we eat can directly impact air pollution, beyond just personal protection. Check out Flashback Friday: Diet and Climate Change: Cooking Up a Storm.

In health,

Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live presentations:

Contaminants Found in 90% of Herbal Supplements Tested


The majority of dietary supplement facilities tested were found noncompliant with good manufacturing practices guidelines.

“The U.S. public is not well protected” by current dietary supplement recommendations, an issue I explore in my video Dangers of Dietary Supplement Deregulation. Sometimes, there is too little of whatever’s supposed to be in the bottle, and other times, there’s too much, as I discussed in my video Black Raspberry Supplements Put to the Test. In one case, as you can see at 0:20 in my video, hundreds of people suffered from acute selenium toxicity, thanks to an “employee error at one of the ingredient suppliers.” Months later, many continued to suffer. Had the company been following good manufacturing practices, such as testing their ingredients, this may not have happened. In 2007, the FDA urged companies to adhere to such guidelines, but seven years later, the majority of dietary supplement facilities remained noncompliant with current good manufacturing practices guidelines.

What are the consequences of this ineffective regulation of dietary supplements? Fifty-thousand Americans are harmed every year. Of course, prescription drugs don’t just harm; they actually kill 100,000 Americans every year—and that’s just in hospitals. Drugs prescribed by doctors outside of hospital settings may kill another 200,000 people every year, but that doesn’t make it any less tragic for the thousands sickened by supplements.

Sometimes the supplements may contain drugs. Not only does a substantial proportion of dietary supplements have quality problems, the “FDA has identified hundreds of dietary supplements…that have been adulterated with prescription medications” or, even worse, designer drugs that haven’t been tested—like tweaked Viagra compounds. About half of the most serious drug recalls in the U.S. aren’t for drugs but for supplements, yet two-thirds or recalled supplements were still found on store shelves six months later.

There is also inadvertent contamination with potentially hazardous contaminants, such as heavy metals and pesticides in 90 percent of herbal supplements tested, as you can see at 2:09 in my video. Mycotoxins, potentially carcinogenic fungal toxins like aflatoxin, were found in 96 percent of herbal supplements. Milk thistle supplements were the worst, with most having more than a dozen different mycotoxins. It’s thought that since the plant is harvested specifically when it’s wet, it can get moldy easily. Many people take milk thistle to support their livers yet may end up getting exposed to immunotoxic, genotoxic, and hepatotoxic—meaning liver toxic—contaminants. How is this even legal? In fact, it wasn’t legal until 1994 with the passage of the Dietary Supplement Health and Education Act. Prior to that, supplements were regulated like food additives so you had to show they were safe before they were brought to market—but not anymore. Most people are unaware that supplements no longer have to be approved by the government or that supplement ads don’t have to be vetted. “This misunderstanding may provide some patients with a false sense of security regarding the safety and efficacy of these products.”

This deregulation led to an explosion in dietary supplements from around 4,000 when the law went into effect to more than 90,000 different supplements now on the market, each of which is all presumed innocent until proven guilty, presumed safe until a supplement hurts enough people. “In other words, consumers must suffer harm…before the FDA begins the slow process toward restricting [a] product from the market.” Take ephedra, for example. Hundreds of poison control center complaints started back in 1999, increasing to thousands and including reports of strokes, seizures, and deaths. Yet the FDA didn’t pull it off store shelves for seven years, thanks to millions of dollars from the industry spent on lobbying.

What did the companies have to say for themselves? Metabolife swore that it had never received a single report of a single adverse effect from any customer. “According to the company, Metabolife had a ‘claims-free history’” when in fact it had gotten 14,000 complaints from customers, but covered them up. Basically, “dietary supplement manufacturers have no realistic accountability for the safety of their products,” and the industry trade organizations have been accused of responding to legitimate concerns with “bluster and denial.” Yes, but are these criticisms of dietary supplements just a Big Pharma conspiracy to maintain its monopoly? No. Big Pharma loves dietary supplements because Big Pharma owns dietary supplement companies to dip into the tens of billions in annual sales.

Isn’t the supplement issue insane? For more, check out:

More than a hundred thousand people are killed every year by pharmaceuticals? Learn more:


Supplement Labeling Fraud is Widespread

The regulation of dietary supplements in the United States has been described as “too little, too late.” “Dietary supplements may be adulterated with dangerous compounds, be contaminated, fail to contain the purported active ingredient, or contain unknown doses of the ingredients stated on the label; be sold at toxic dosages; or produce harmful effects” in other ways. As I discuss in my video Black Raspberry Supplements Put to the Test, “[i]f the composition and quality of ingredients cannot be reliably ensured, the validity of research on dietary supplements is questionable. Moreover, the health of the US public is put at risk.”

A private, third-party company that has independently tested thousands of supplements “identifies approximately 1 in 4 with a quality problem” because it either does not contain what it says it contains, is “of substandard quality,” or is contaminated in some way.

Let’s look at an example. I’ve produced a few videos on the remarkable properties of black raspberries, including one on oral cancer. These berries can’t always be found fresh or frozen, so how about black raspberry supplements, which are available in stores and online? At 0:56 in my video, I show a bottle of Pure Black Raspberry by Pure Health, that says “Fresh – Raw – Pure” right on the label. Sounds good, don’t you think? When we look at the back of the bottle, the label says it contains only seedless black raspberry powder “and absolutely nothing else!” It’s nice to see there are no fillers or artificial ingredients, so why not plunk down $23.77 for a bottle? Well, it turns out we’ve been had.

The first clue is that the image on the front of the label is actually blackberries that had been Photoshopped to look like black raspberries. Pure Health couldn’t even be bothered to put a real image on its fake supplement! The second clue is that the “[d]ark olive-brown-black powder in [the] capsule did not look like berry powder and had a medicinal odor,” according to the researchers. So, it was put it to the test, and, indeed, there was no black raspberry at all. Instead of promoting the fact that the Pure Black Raspberry contains only seedless black raspberry powder “and absolutely nothing else,” the company should have just listed that the bottle contains “absolutely nothing” period—or, at least we hope it contains nothing. Who knows what’s actually in the capsules!

The researchers tested every black raspberry product they could find, and, even of the ones with the correct picture on the front and with powder that actually looked like it came from real black raspberries, more than a third appeared to have no black raspberry fruit at all. “At the moment, a consumer who assumes the US dietary supplement marketplace is free from risk”—or is even honest—“is unfortunately naive.”

How widespread is this deception? Researchers used DNA fingerprinting techniques to test the authenticity of 44 herbal supplements from a dozen different companies. As you can see at 2:33 in my video, less than half of the supplements were authentic and actually contained what they said they did. Most contained plants not listed on the label and product substitution, and many “contained contaminants and or fillers,” also not listed on the label. This isn’t just fraud: Some of this deception could really hurt people. For example, one St. John’s wort supplement contained no St. John’s wort at all. Instead, it was actually senna, which is an herbal laxative that “can cause adverse effects such as chronic diarrhea, cathartic colon, liver damage, abdominal pain, epidermal [skin] breakdown and blistering.” In the video at 3:09, you can see how the 12 companies did. Tested products from only 2 of the 12 companies appeared to be completely authentic, with the remaining 10 companies’ products containing filler, product substitution, and/or contaminents. Herbs only work if they’re actually present. Indeed, this study found that 80 percent of the manufacturers in the supplement “industry suffer[] from unethical activities…”.

“Until US dietary supplement products are better regulated and quality control standards for safety, purity, and dosage are defined and endorsed, the safer source for dietary phenolics,” or phytonutrients, “as a consumer is from food intake.”

For more on supplement company shenanigans, see:

What’s so special about black raspberries? Reversal of cancer progression, for starters! See Black Raspberries vs. Oral Cancer and Best Fruits for Cancer Prevention.

In health,
Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live presentations: