Fat burners claim to speed up weight loss, but many are unregulated and don’t actually work — and in some cases, are actually dangerous. What you take and how you use them is key.

Fat burners are any dietary supplements or related substances that claim to burn excess fat from your body.

Some of these fat burners are naturally occurring. These include caffeine and yohimbine.

But many are ineffective at best or dangerous at worst. Your body can naturally burn fat through diet and exercise. Using additional supplements can interfere with your metabolism or overall health.

The Food and Drug Administration (FDA) has a limited role in regulating dietary supplements. This means that supplement manufacturers can put almost anything in their products.

There’s no evidence that fat-burning pills or supplements can effectively burn fat.

But they do typically contain ingredients that won’t hurt you in small doses when taken alone. Some are even proven to help burn fat when they’re consumed naturally.

But it’s impossible to know for sure how much is used in the supplement. The amount might be off — even if the bottle specifies an amount on the label. It’s hard to know how the manufacturer assessed the total amount.

Manufacturers don’t always list all the ingredients on the label. And regulators aren’t bound to investigate these products fully unless there are complaints or medical consequences from using these supplements.

This can be a recipe for disaster if you’re allergic to ingredients in the supplement or if you take too much of a certain nutrient.

So let’s go over five of the most popular science-backed fat-burning substances that you can consume in many readily available natural forms.

Caffeine

Caffeine can be dangerous in high doses. But natural caffeine in coffee or tea is safe in moderation. Coffee without extra sugar or additives contains numerous antioxidants with health benefits.

Several studies have suggested that caffeine can actually boost your metabolism by up to 11 percent.

This means that your body uses fat to produce energy more efficiently. And exercising regularly and maintaining a healthy diet will more easily burn fat as a result.

A 2019 review of several studies determined that “caffeine intake might promote weight, BMI, and body fat reduction.”

Green tea extract

Green tea is lauded for its purported health benefits. This includes helping you lose weight by burning fat.

Natural green tea has some caffeine. But the real powerhouse ingredient in green tea is an antioxidant called catechin.

A 2010 review in the journal Physiology and Behavior suggests that catechins work alongside caffeine to enhance metabolism and thermogenesis. This is a process that allows your body to burn fat to produce energy.

Protein powder

Protein is a crucial ingredient needed to help burn fat. It not only enhances your metabolism, but it also suppresses your appetite by reducing a hunger-stimulating hormone called ghrelin.

According to a 2017 study, participants who regularly ate a high-protein diet had significantly more weight loss than those who did not. However, even participants who did not consistently maintain a high protein diet but did increase protein consumption lost weight.

There are numerous options that are low in sugar and artificial additives.

Try adding protein powder as a supplement to your diet to ensure you’re regularly getting enough. Stick to about 25 to 50 grams of protein powder each day.

Soluble fiber

Soluble fiber is one of two types of fiber. The other one is insoluble.

Soluble fiber creates a sort of gel in your gut by absorbing water. This helps increase hormones like GLP-1 that make you feel full while suppressing appetite hormones like ghrelin.

A 2010 study found that increasing natural soluble fiber in your diet may help your body take in less fat and calories, which allows you to burn excess fat.

Yohimbine

Yohimbine comes from the bark of a tree called Pausinystalia yohimbe. It’s famous as an aphrodisiac. But it also has some suggested fat-burning potential.

Yohimbine blocks alpha-2 adrenergic receptors to which adrenaline normally binds. This lets adrenaline stay in your body longer to burn fat to produce energy.

A small 2006 study of 20 professional soccer players found that taking yohimbine reduced their body fat composition by 2.2 percent. This doesn’t sound like a lot. But 2.2 percent is a large amount when you’re already a fit athlete with little body fat.

Here are some possible side effects of these fat-burning substances and some precautions you can take to avoid those effects:

  • Regularly consuming caffeine will make it less effective over time.
  • Taking too much caffeine in a short period can make you feel anxious, jittery, or exhausted.
  • Using too much protein powder, especially if it has extra sugar or additives, can contribute to weight gain.
  • Using too many natural “fat burners,” especially supplements, can lead to acute liver failure.
  • Taking yohimbine has been linked to nausea, anxiety, panic attacks, and high blood pressure.

The best way to lose weight is the classic way: diet and exercise.

The most efficient way to do this is by creating a caloric deficit, or consuming fewer calories than you burn off through exercise.

Read more about how a caloric deficit works.

Fat-burning supplements and creams aren’t nearly as effective as they’re marketed to be. In some cases, they can make your fat-burning efforts more difficult.

Opt for a natural route instead: Consume fat-burning ingredients in their natural form, such as in coffee or tea, and try to take in fewer calories than you burn off to reach an optimal caloric deficit.