What Are Toxins?

According to the diet industry, toxins should rank high on our list of things to worry about. Numerous health products claim to cure symptoms like headaches, sluggishness, and even chronic disease by flushing the substances from our systems. But don’t be too quick to order a pack of foot pads or drink nothing but cayenne pepper lemonade for 10 days straight: Most health experts will tell you that toxins aren’t exactly the nutritional bogeymen they’re made out to be.

One such expert is Peter Thorne, a professor at the University of Iowa, head of the College of Public Health’s Department of Occupational & Environmental Health, and director of its Environmental Health Sciences Research Center. In a conversation with mental_floss, he said that the first thing most people get wrong when talking about toxins is the basic meaning of the term. “The words toxin, venom, toxicant, xenobiotic—these all have very specific meanings in the realm of toxicology,” Thorne says.

A toxin is defined as any harmful substance produced by a living organism. Some examples are the toxic chemicals injected by animals like bees, snakes, and sea urchins (which are all technically venom, a toxin subset). Other poisons that fall under the toxin umbrella include those produced by a dart frog or the leaf of a hemlock plant.

Toxic substances added to the environment by people, on the other hand, are called toxicants. When diet commercials and health magazines use the word “toxins,” this is usually what they’re referring to. So, by definition, toxins are always “all natural”—though whether or not that label carries any weight is a different story.

Going on a juice cleanse obviously won’t do much to treat a snakebite, but is it an effective way to rid your body of toxicants like pesticides? Thorne says that’s a question most people don’t need to be asking in the first place. “We’ve evolved with a whole cadre of metabolic enzymes that process most of the toxicants to which we’re exposed,” he says. When late-night infomercials warn that toxins (a.k.a. toxicants) can’t be avoided as long you're someone who eats, drinks, and breathes, they’re not entirely wrong. The one part they usually fail to mention, however, is that humans have evolved to become pretty good at dealing with these substances on our own.

The majority of the low-level toxicants that enter our bodies—whether through the air we breathe or the food we ingest—are metabolized and expelled by organs like the liver and kidneys. Urine, excrement, and exhalations are a few of the exit routes toxicants can take from your system. “For the vast majority of what we’re exposed to, it has no long-term effect,” Thorne says.

Complications arise when people come into contact with toxicants in high doses. If you’re the resident of a place with dangerously high arsenic levels in the water or significant amounts of air pollution, for example, then your body may be taking in too much toxic material to process. Fortunately, agencies like the FDA and EPA (Thorne is a member of the latter's science advisory board) exist to determine safe toxicant levels and limit how much the public is exposed to.

Industry regulations are intended to ensure that toxicants are something most U.S. citizens don't have to think twice about. But for a small percentage of the population, even limited exposure to toxicants can be detrimental to their health. People born with certain environmental sensitivities or genetic mutations, for example, aren't as well equipped to handle toxicants as those without them. In these rare cases, doctors may suggest medication or dietary changes as treatments. What they likely won’t recommend is one of the many home “detox” remedies that can be found over the counter.

The health guidelines toxicologists like Thorne set forth are the result of years of rigorous study. Products like detoxifying teas, face masks, and colon-cleansing capsules often have no research to back up their effectiveness. “For the vast majority of people, if you’re living a healthy lifestyle and you have [a well-balanced] diet, you have no need to even think about some of these extreme measures I’ve seen advertised,” Thorne says. “I’ve seen some evidence out there to suggest they’re [in] no way valuable or effective—or needed.”

Toxicology research has brought us a long way in just the past several decades: Lead is no longer added to our gasoline and mercury is no longer a key ingredient in hat-making. As new research broadens our understanding of the area, there’s one thing we can keep in mind: More often than not, detoxing is a job best left to your organs.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at bigquestions@mentalfloss.com.