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Let’s be real: If you’re looking to lose some weight, it takes a lot of work. Naturally, pills that claim to lead to rapid weight loss seem like an easier option than the old-fashioned diet and exercise route (so archaic, right?).

The majority of these infomercial-ready pills work by suppressing your appetite, increasing fat burning, or reducing how you absorb calories. But just because they can help you drop weight doesn’t mean it’s necessarily going to last — or that it’s safe.

Most of these pills are considered dietary supplements, which do not have to be regulated by the FDA in any way, meaning they haven’t necessarily been tested or approved for safety and may not even work as advertised.

The FDA reports that many weight loss supplements are tainted with dangerous ingredients. Because of this, weight loss pills have an unfortunate connection to health problems and even death.

Dietary changes and exercise should always be your go-to before adding supplements or medication. But there is evidence that some weight loss pills can be used safely to help you hit your goals.

We’ll break down 13 popular types of weight loss pills to tell you what works, what’s a total sham, and any harmful side effects you could experience.

Health-food lovers are all about apple cider vinegar (ACV). It’s often touted as a solution for health-related issues, especially fat burning and weight loss. But is it legit?

How they work

ACV is essentially fermented apples that turn into vinegar. The acetic acid, B vitamins, and antioxidants in ACV all offer some health benefits. A small study published in 2004 found that vinegar may have a role in regulating blood sugar after meals.

In a 2018 study on rats with obesity, the antioxidant properties of ACV suppressed obesity-induced oxidative stress and reduced triglyceride levels, which can cause conditions such as heart disease. Rats aren’t humans, though.

A small 12-week study published in 2018 found that participants who supplemented a reduced-calorie diet with ACV lost more weight than those who only followed the diet.

Side effects

The acidity of ACV can give you some gnarly acid reflux, but it most likely won’t be as bad if you’re taking ACV in pill form. ACV can also interact with other diuretics or insulin. You should avoid ACV supplements if you have type 1 diabetes.

Additionally, if you have chronic kidney disease, your kidneys could have trouble processing the extra acid in your body.

Are they BS?

Most likely. There just aren’t enough human studies on ACV to say it helps you lose weight. The bottom line is that it can help your metabolism and blood sugar levels, which could help your overall health when paired with the right diet and exercise.

Keto was super popular in 2018 and 2019, so chances are you’re aware of this diet in which you nix carbs for fat. “Keto pills” is an umbrella term for anything that claims it can help get your body into ketosis.

The “Shark Tank” favorite Rapid Tone is one of these products. Ketosis is your body’s process of using fat for energy (and thus producing ketones) instead of its usual carbs-for-energy route.

The result is that you’ll burn more fat (and you get to eat cheese — bless!). So, if you want to get into ketosis ASAP, there’s a pill for that.

How they work

Most keto pills use salts that are modified to burn fat (aka put your body into ketosis by raising your blood ketone levels). With these pills, you can supposedly get the benefits of ketosis without making drastic dietary changes.

Side effects

Sounds like the perfect pill, right? Well, there’s a catch (we just can’t have nice things). Keto pills can wreak havoc on your metabolism.

Research has shown that people in a ketogenic state have increased satiety hormones and decreased hunger hormones, which helps suppress appetite.

But once they ditch the pills, those hormones suppressing appetite increase to way above where they were before, so the weight comes back.

Are they BS?

Technically, no — but in the long run, yes. The pills are effective at getting your body into a fat-burning state of ketosis. But even though you’ll lose weight fast, it’s very likely the weight will return when you stop taking the pills.

Think you can pee off the pounds? Water pills say they can help you do just that.

How they work

Over-the-counter and prescription water pills are diuretics, meaning they make the pee just flow out of you by triggering your kidneys to get rid of extra water and salt. This, in turn, helps you lose water weight and bloat.

Side effects

Water pills are really intended to treat high blood pressure and can interact with other medications. Plus, they can overload your kidneys, leading to kidney failure (yikes!).

And then there’s the cherry on top: dehydration. Frequent urination can increase your chances of getting dehydrated if you’re not replenishing your fluids.

Are they BS?

Yes. You’ll probably only lose 3 to 4 pounds of water weight, not actual fat. A 2004 study found that water pills had basically no effect on weight loss. The pounds will return once you go back to your usual lifestyle.

Plus, a lot of over-the-counter water pills are just unregulated capsules of caffeine and herbs that are too weak to deliver any effects.

Caffeine is the sweetheart of stimulants for keeping us awake and focused throughout the day. (We love you, coffee!) It’s also an ingredient in many weight loss supplements and frequently stars on its own in pill form.

How they work

Caffeine is said to boost metabolism and increase fat burning.

Side effects

Too much caffeine can make your heart race and cause anxiety, vomiting, and jitters. It’s safe to consume 400 to 500 milligrams of caffeine a day, but if you’re drinking caffeinated beverages and taking these pills, it’s easy to go overboard.

Are they BS?

Caffeine may aid in weight loss, but it’s not likely to work for very long, since your body builds up a tolerance to its effects.

A 2015 study comparing people who drank coffee and caffeinated beverages to those who did not found that the caffeinated peeps lost more weight.

Another miracle elixir from the health-food community is green tea, which also comes in a pill form as green tea extract with other fat-burning ingredients.

How it works

The general idea is that the caffeine and antioxidants in green tea supplements can aid in fat burning.

Side effects

There have been reports of liver damage in people who took green tea extract.

Is it BS?

According to a 2013 review of studies, some research has found that green tea extract can help with weight loss, but there’s not enough evidence to say for sure. It definitely won’t just melt away the pounds without diet changes and exercise.

Still on the caffeine train, green coffee beans (unroasted coffee beans) are another big weight loss supplement on the market.

How it works

The caffeine in green coffee beans is thought to help weight loss by burning and inhibiting fat. Chlorogenic acid in the extract slows down the breakdown of carbs in your digestive system.

Side effects

The same side effects as caffeine — plus, diarrhea is possible thanks to the chlorogenic acid. You can also be allergic to green coffee beans.

Is it BS?

Maybe. An 8-week study found that subjects taking green coffee bean extract had more weight loss and reduced BMI and that the supplement could help suppress appetite for weight loss.

A 2011 review of three clinical trials also found the supplement helped with weight loss. But there haven’t been many promising studies that weren’t funded by supplement companies.

One of the most marketed and well-known weight loss pills, Hydroxycut is extremely controversial.

Over the years, the supplement has caused liver damage and heart-related deaths and has been recalled by the FDA numerous times for containing harmful ingredients like ephedra.

Since it went back on shelves in 2010, Hydroxycut has changed its ingredients, but most medical professionals will caution you against using it.

How it works

Today’s Hydroxycut is a mix of caffeine, lady’s mantle extract, wild olive extract, komijn extract, and wild mint extract.

There are few to no studies on the different types of Hydroxycut, but research has found that caffeine and some of the other herbs the supplement contains can help with weight loss.

Side effects

Like too many cups of coffee, the caffeine in Hydroxycut can cause side effects such as anxiety, nausea, diarrhea, and jitters.

Is it BS?

Most likely, but it’s hard to say for sure. There are no reputable studies on the supplement itself, and online reviews are extremely mixed.

Alli is the lower-dose, over-the-counter version of orlistat (it’s also sold as the prescription drug Xenical).

In 2010, the FDA published a safety review of orlistat when people reported serious liver damage. The FDA could not find evidence that orlistat was the cause, but Alli changed its formula anyway.

How it works

The orlistat in Alli helps your intestines absorb less dietary fat by inhibiting the digestive enzyme lipase that breaks down fat. When you take Alli with a meal, roughly 25 percent of the fat you eat won’t be broken down — it’ll simply go straight through your bowels.

Side effects

Taking Alli can cause digestive issues like abdominal pain, gas, oily stools, and more bathroom visits. Headache, back pain, and upper respiratory infection are also possible.

Is it BS?

This one looks legit if you eat right and exercise. Studies have shown that people who take orlistat with a calorie-restricted diet and exercise will lose more weight.

But you don’t necessarily need it: A 2010 study actually found that eating a low carb diet was just as effective for weight loss as taking orlistat while eating a low fat diet.

Garcinia cambogia is a fruit that looks like a little green pumpkin. An extract from it is sold in pill form for weight loss.

How it works

Garcinia cambogia contains hydroxycitric acid (HCA), which is thought to suppress appetite.

Side effects

No serious side effects have been reported — just some minor digestive issues.

Is it BS?

Maybe. A 2011 study found that garcinia cambogia led to an average weight loss of about 2 pounds over several weeks. But more research is needed to clarify whether it works.

Glucomannan is an herbal supplement that’s extracted from elephant yam as a water-soluble dietary fiber.

How it works

Glucomannan is kind of a science experiment in your gut. Once ingested, it absorbs water and turns into a gel. This helps you feel full.

Side effects

Glucomannan can cause bloating, farting, and soft stools. It can also mess with some medications.

Is it BS?

It’s probably legit. Research shows that glucomannan works when paired with a healthy diet and can also improve blood pressure, glucose levels, and cholesterol. A 2005 study found that glucomannan helped participants lose weight.

Conjugated linoleic acid, aka CLA, is a natural fatty acid used as a supplement for weight loss.

How it works

CLA is thought to reduce appetite, break down fat, and boost metabolism.

Side effects

CLA can cause digestive issues and some nasty side effects (including fatty liver, inflammation, and insulin resistance) if used long-term.

Is it BS?

It works, but it can really mess you up if you keep taking it. A 2007 review of 18 studies found that participants taking CLA consistently lost weight for 6 months. However, the side effects are very serious and worth consideration.

Back to the hippy natural supplements! Forskolin is extracted from the roots of the Indian coleus plant, a cousin of mint. Not much is known about this plant or how it affects weight loss.

How it works

Forskolin is thought to help burn fat by raising your cells’ level of cyclic adenosine monophosphate (cAMP), a compound that helps break down stored fat.

Side effects

This supplement’s effects on your body — including side effects and safety — are largely unknown.

Is it BS?

As with pretty much everything else about forskolin, we don’t really know. But it’s best to avoid this pill until more research has been done.

There’s simply not enough data and too much conflicting information to tell if it’s safe, let alone if it works.

Bitter orange has a variety of uses in traditional Chinese medicine, such as helping with heartburn and nasal congestion and aiding in weight loss.

How it works

The synephrine in bitter orange has very similar weight loss properties to ephedrine, the main component of ephedra (which was banned by the FDA for causing heart attacks and strokes).

While it’s similar to ephedrine, synephrine is less potent. It reduces appetite and helps you burn more fat.

Side effects

Similar to its evil twin, the synephrine in bitter orange can cause heart, digestive, and circulation issues and is potentially addictive.

Is it BS?

There haven’t been many studies on synephrine. The success of ephedrine shows that it’s probably legit, but it comes with a cost. The side effects can be major, and the NCAA lists it as a banned stimulant for its athletes.

OK, so technically there are more than 13 pills on this list. There are several prescription drugs that aid in weight loss and pretty much do the same thing.

The most popular prescription weight loss drugs are Contrave, Belviq*, Phentermine, and Qsymia. Metformin, a diabetes medication, might also help with weight loss.

*Belviq (lorcaserin): In February 2020, the FDA requested that Belviq be removed from the US market. This is due to an increased number of cancer cases in people who took Belviq compared to placebo. If you’re prescribed or taking Belviq, stop taking the drug and talk with your healthcare provider about alternative weight management strategies.

How they work

Prescription weight loss pills generally work by suppressing appetite. Most are designed to support long-term weight loss plans. Metformin is actually a diabetes medication used to regulate blood sugar levels.

Side effects

Prescription weight loss pills can cause nausea, constipation, or diarrhea. Phentermine also stimulates the central nervous system, which increases your heart rate and blood pressure.

The bottom line

  • Weight loss pills vary greatly in their ingredients and effectiveness. Some have been proven to help with weight loss, others not so much.
  • If you’re interested in trying a weight loss pill, always consult your healthcare provider to determine which option is right for you and safe to use.
  • Remember that diet, exercise, and a long-term plan created with a healthcare provider are ultimately your best options for successfully losing weight and keeping it off.
  • Weight loss pills can be a quick fix, but they won’t help you maintain a healthy weight in the long run and could even be harmful.
  • Want more science-backed info on weight loss? Check out our articles on how to lose body fat, exercises for weight loss, and issues that may be preventing you from losing weight.