Need to Know
  1. Ingredients in diet pills are generally unsafe
  2. Side effects are serious and range from person to person
  3. Diet pills are not regulated by the FDA

Diet pills. The name alone conjures up flashy ads in the back of magazines, promises of magic solutions, or horror stories suitable for Lifetime original movies.

First debuting in the late 19th century, these little round pills seemed like a beacon of hope and a ray of shining light in a world where being thin was golden. People started to take these mystery pills, hoping that it would help them to fit into a smaller dress or win over their secret love, only to experience serious side effects. From increased blood pressure to nausea and even death, these original pills continued to exist until the 1960s.

Fast forward to today, you would expect me to tell you how so much innovation and discovery has occurred since the 1800s, right? Wrong. Not much has changed at all, and diet pills still come with scary side effects and not much promise of that forever-thin waistline. The easiest thing would be to tell you that diet pills are not good for you and you should stay away from them. Period.

But here at Spright, we want you to learn about the facts and know the reasoning behind every health and wellness decision you make. If you’ve found yourself on the road of trying a diet pill or just doing some diligent research, let’s talk about this. We brought expert help from Marjorie Cohn, a registered dietitian and national spokesperson for the Academy of Nutrition and Dietetics.

So, what is a diet pill?

From a regulatory standpoint, there is no definition of what a diet pill is. If we were to look at what constitutes a supplement, it’s any sort of pill that is considered to have specific health effects. If it’s a diet pill, common varieties include appetite suppressants, metabolic boosters, or carb or fat blockers.

What are the types of diet supplements?

  • Appetite suppressants or metabolic boosters, including caffeine, green tea, or ma huang
  • Laxatives, which are meant to purge the body of calories (although it doesn’t actually work that way)
  • Diuretics, where you lose fluids
  • Fat and carb blockers, which stop the absorption of fat and carbs (this also results in a laxative effect because your body isn’t absorbing the fat and carbs)

Why are diet supplements not FDA approved or regulated?

No supplement needs to be approved or regulated. That’s what so scary about diet pills and the millions of other supplements that are on the market. There is no regulatory standard that these pills have to go through in order to be put on the market.

As stated on the Food and Drug Administration’s site, “Under the Federal Food, Drug and Cosmetics Act (as amended by the Dietary Supplement Health and Education Act of 1994), dietary supplement firms do not need FDA approval prior to marketing their products. It is the company’s responsibility to make sure its products are safe and that any claims made about such products are true.”

In fact, the FDA doesn’t become involved until reports of side effects or problems with the supplements are reported. If you were to buy any type of supplement, whether it be a diet pill or something as simple as a B vitamin, you want to check that it has been third-party tested, which means that the supplement company itself pays an outside organization to test their supplements for purity, strength, dissolution. Most diet pills are not third-party tested, but if it is it will be on the label.

TIP: look for the USP-verified symbol, which stands for United States Pharmacopeia. This means a company voluntarily submitted their product for USP review; the verification label indicates the supplement actually contains what it claims to, among other things.

There are other third-party testing groups, but the USP is the common and most widely recognized.

Essentially, anyone can just make a diet pill and put it out there?

Pretty much. There are some regulatory standards that must be met to put any sort of supplement on the market, but the supplements are not tested by the government before they are available for sale to the public.

With diet pills, it’s particularly hard to know everything in them (or not in them). Most contain some form of caffeine, though it’s listed under many different aliases. Taking one of these pills may be like having 10-12 cups of coffee in a pill. That’s a lot of stimulant! The possible side effects of that alone include rapid heart rate and dizziness. When you come down off caffeine, it may cause extreme fatigue, dehydration, and/or mood swings.

Speaking of side effects, what’s in a diet pill that makes you feel depressed?

It’s not exactly what’s in the pill, but rather a commonly found symptom (possible side effect) among users.

People may get addicted to and/or become dependent on these diet pills, feeling as though they can’t lose weight or keep their weight down unless they’re taking a pill. Usage may also affect serotonin levels, which leads to mood swings, insomnia, and anxiety.

What are other common side effects that diet pills cause?

Physically, in addition to rapid heart rate and heart palpitations, diet pills can cause poor concentration and muscle weakness and soreness, especially if it’s related to being overly dehydrated. Other people report light-headedness, dizziness, fainting, and nausea.

Any sort of GI symptoms may be a side effect as well. Some of these pills have a combination of diuretics, laxatives, and stimulants. So you’re kind of hitting every system. Your heart is racing, you’re excreting excess water, and what you do eat is causing a potential laxative effect. It really stresses the body.

What is our final takeaway?

Combining healthier eating with consistent exercise is a much safer and more effective way to manage weight.

Dietary supplements are not regulated by the FDA. It is the supplement company’s responsibility to make sure that the product is safe and claims made about such products are true, which doesn’t always happen. For the most part, any studies that are cited in the box are being conducted by the company that’s selling the product. In other words, they’re often (if not always) biased.

Do your research and know what you are putting into your body.

There is no pill out there that’s going to be the weight loss magic bullet. If you’re looking for a way to kick-start a healthy lifestyle, we recommend eating simple, minimally processed foods as much as possible and starting a regular activity routine. It’s not as easy as taking a pill, but it will certainly be more effective in the long run, keeping you on an healthy path toward change.

This interview has been edited for brevity and clarity.