The health and fitness industry has grown to become a behemoth. If we group healthy eating and nutrition products (which includes vitamins and supplements, weight-loss specialty food, and the like) in with fitness and exercise (gyms, group classes, exercise products) annual sales top half a trillion dollars. Any market making that kind of money is going to attract some shysters.

Add to that the fact that nutrition and exercise science are still young and frequently changing, and unfortunately you have a marketplace filled with consumers who are easily misled. Maybe this is why the industry is so dominated by fad products (Thighmasters, minimalist shoes, ab-rockers) and fad diets.

What upsets me more than anything is the huge number of customers spending money on products they don’t understand, products they would never buy if they knew the reality behind them. Here are a few of my top offenders.

1. Chiropractic

I want to start with a disclaimer here: I’m not saying chiropractors are no good; many chiropractors study and practice physical therapy, acupuncture, massage, and other techniques proven by science to have health benefits. All criticism is directed at chiropractic, a specific theory and practice that not all chiropractors actually embrace.

What’s the difference? Chiropractic was developed in the late 1800s, a time when traveling medicine shows sold various ‘health tonics,” and chocolate bars were considered fitness food. Daniel David Palmer was a magnetic healer [ahem] who “discovered” that misalignment of bones, especially in the spinal column, was the reason for all disease. And I mean ALL disease. Here’s a direct quote:

“A subluxated vertebra … is the cause of 95 percent of all diseases … The other five percent is caused by displaced joints other than those of the vertebral column.”

Palmer developed spinal manipulation techniques to repair these misalignments, or “subluxations,” and in 1897 (shortly after he claimed he cured a man of blindness by manipulating his spine) he opened a school in Davenport, Iowa, to teach his techniques, now known as “Chiropractic.”

Please note that Palmer had no education nor experience as a doctor. He was, however, an accomplished beekeeper before he went on to become a faith healer. The key to Chiropractic was his belief in “Universal Intelligence,” a supernatural order that pervades the Universe (the Force, basically) and its relationship to the structural integrity of the human body. Palmer was dead-set against vaccination, convinced as he was that spinal misalignment was the reason for all diseases and disorders. He died in 1907 of typhoid fever.

Chiropractic, however, caught on. To this day, there are chiropractors in almost every part of the world who have dedicated their lives to his teachings, and many health insurance plans even cover chiropractic treatment. Most scientific studies have found little to no physical benefit in chiropractic practice, and some caution that severe injury and even paralysis can result. Those chiropractic treatments that have shown statistically significant benefits have much in common with other forms of physical therapy, and have been adopted by physical therapists and physicians.

If you currently go to a chiropractor, it’s entirely possible–even likely–that the person you’re seeing has no formal training in Chiropractic, as invented by D.D. Palmer. They are just as likely to be a licensed physical therapist who can do real good, but finds it more marketable to put the word “chiropractor” on their shingle. That said, before you let that person toy with the bony tube that protects your central nervous system, you may want to ask them a few questions about “subluxation” and “universal intelligence,” and make sure they are guided by a scientific understanding of physiology, and not some 19th-century crackpot superstition.

2. Homeopathy

This one bothers me more than just about any other. What does the word homeopathic mean? You don’t really know for sure, right? But you probably think it’s basically a synonym for “natural” or “alternative medicine.” But you’re wrong.

The word “homeopathic” on a product by definition means it contains nothing but water.

I know you don’t believe me. Nobody ever believes me. So here’s a link. Go ahead and read it if you want, but here’s a basic summary:

Like Chiropractic, homeopathy has been with us for a long time–in this case, since the late 1700s. Its creator, Samuel Hahnemann, was at least an actual doctor, albeit and 18th century one. He believed that substances had innate properties that could be passed to other substances they came into contact with–like water–and he developed the practice of “homeopathic dilution,” in which water is exposed to some object or substance, and then diluted over and over again.

Essentially, if you put a single drop of antibiotic in an Olympic-sized swimming pool, Dr. Hahnemann believed the water in that swimming pool could treat infections. Dr. Hahnemann had never heard of antibiotics, of course, or infections. In the era when he practiced medicine, germs hadn’t yet been discovered and sickness was believed to be caused by something called miasms. So it’s hard to blame him, it’s not like anybody knew better back then.

…and yet homeopathic products continue to be sold today, in almost every store that sells health products. Even though that little jar doesn’t contain so much as a single molecule of anything except water. There are homeopathic healers, and homeopathic “medical associations,” even though study after study has shown that homeopathy is exactly as effective as a placebo.

Dr. Hahnemann, by the way, wound up with his name on a hospital in Philadelphia. They practice real medicine there, though–kidney transplants and such–not homeopathy.

3. Cleanses

Here’s a general guideline by which you should begin to live your life: If a product or diet claims to “remove toxins,” you should not spend your money on it.

It’s not that toxins aren’t a real thing, or that they aren’t bad for your body. They are real, and they are bad. But your body has a fantastic mechanism for removing those toxins all by itself–it’s called your anatomy. Various organs, including your liver, kidneys, stomach, intestines, your heart and lungs, even your bone marrow, all work together to constantly filter out and remove all the things that are bad for you.

Okay, almost all the things. Some toxic substances, like heavy metals, do have a way of accumulating because your body has no way to remove them, but you don’t get them out by taking some herb or fad supplement. You go to the hospital for chelation, an expensive and dangerous procedure that cannot be replaced by a pill, at least not yet.

Everything else? Your body has that covered. All you have to do is drink enough water, and eat a moderately healthy diet. I’m not even talking a “healthy diet” in the pop-culture, ‘eating clean’ sense. Just enough of the nutrients your body needs to work effectively, and almost every American gets that.

So why do products like cleanses continue to sell? Well, partly it’s because companies are intentionally deceptive. Maybe you remember that pill from a few years ago that made people poo a big nasty snake-like thing made from a white rubbery substance? The manufacturer claimed the white rubbery goo was “toxins” that had been lurking in the digestive tract, but it turns out the pills contained substances that react inside the body to form–you guessed it–a thick, rubbery white goo. Then there were those foot pads, the ones that turned black when you stuck them to the soles of your feet from all the “toxins” they sucked out. No, turns out they turned black because the manufacturer included an ingredient that turns black when exposed to heat and moisture–like being held over a steaming pot of purified water, for instance.

The other reason these products continue to sell is because Americans have a lousy mechanism for measuring health. Which brings me to:

4. Almost Any Theme Diet

The cabbage diet. The potato diet. The grapefruit diet. The lemon-cayenne pepper diet. They all work, right? Well, not really.

I’ll tell you a secret about fad diets, that their designers don’t want you to know. They work for two reasons:

  1. Americans define “healthy” as “it made me lose weight.”
  2. Americans eat such a terrible diet, on average, that literally any restriction is going to help us lose weight.

That’s it. There’s nothing else to it. You could literally invent the “ice cream diet,” where you live on nothing but ice cream, and as long as you made sure to stay within certain calorie limits, everyone who tried it would lose weight. Healthy, right? Yeah, no. Not really.

Unfortunately, it’s also the reason many of those diets fail in the long run: They cheat by forcing people into a highly restricted eating pattern, one that is almost never sustainable from a nutritional standpoint, and eventually people crack.

There are a few diets that operate on sound, scientifically-based principles of nutrition. Some, like Zone and Atkins, take those sound scientific principles to extremes–yes, eating a ton of protein and almost no carbohydrates will sort of “trick” your body into dumping weight like crazy–but the problem there is the dieter still isn’t really learning how to eat healthy, they’re either eating branded products that contain the proper nutrient ratio (often courtesy of cheap ingredients like rendered hooves and skin) or eating only bacon, steak, and jerky. Neither of those is going to work for anyone in the long-term.

Now, I have encountered a couple of diets that sort of travel disguised as fad diets. My personal favorite is the “Fat Smash Diet,” which sounds like something Doctor Oz would promote on his modern-day traveling medicine show, but is actually about re-educating people on how to eat healthy. You start out eating nothing but fruits and vegetables for two weeks, and then gradually add back other foods, in descending order of how much you’re supposed to eat. By the end, if you’ve paid attention, you’ve learned eating habits that will carry you through the rest of your life.

But that latest new diet everyone is on? The one where you eat only the left half of avocados, and vegetables beginning with A-K? Yeah, save your money.