In our size-obsessed culture, weight loss is big business. Americans spend more than $2 billion a year on weight-loss pills. But do these so-called “fat burner” supplements work? And more importantly — are they safe?
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“Proceed with caution,” warns registered dietitian Melissa Matteo, RD. To better understand fat burners, Matteo tells us if they work, what’s in them and some healthier and safer alternatives.
What are fat burners?
Fat burners are dietary supplements that might contain natural or artificial compounds. The products claim to help people lose pounds and get a more sculpted shape.
Do fat burners work?
The answer? Maybe. But don’t expect any miracles.
Despite their name, fat burners don’t actually make fat cells go up in smoke. Instead, they attempt to drive weight loss in other ways. They might:
- Increase your metabolism, so you burn more calories.
- Reduce the amount of fat your gut absorbs.
- Suppress your appetite, so you consume fewer calories.
At least, that’s how they work in theory. Some of the ingredients found in fat burners have been linked to small amounts of weight loss. But most of these supplements haven’t been tested in scientific studies.
More importantly, though, fat burners aren’t regulated by the U.S. Food and Drug Administration (FDA). That means manufacturers can make all sorts of claims about their products, even if they have no evidence to back them up. “Because the FDA doesn’t regulate them, we don’t really know their effectiveness,” Matteo cautions.
Common ingredients in fat burners
There are dozens of ingredients in weight-loss supplements, including herbal ingredients and other compounds. Some of the more common ingredients are:
Caffeine stimulates your nervous system and might help burn calories. But supplements can contain a lot more caffeine than coffee, tea, chocolate or other natural sources. Too much caffeine can cause nervousness, jitteriness, insomnia — and even a dangerously high heart rate.
Green tea extract
Many fat burners contain extracts made from green tea. This ingredient might help burn calories and may reduce the amount of fat you absorb from food. “But the amount of weight loss isn’t that significant,” Matteo says. “You’d probably burn more calories by taking a brisk walk each day.”
This compound helps with your metabolism and gives you energy. It’s found in many types of meat and dairy products, and your liver and kidneys make it naturally. But research on its weight-loss benefits is mixed. Too much carnitine can cause nausea, vomiting, diarrhea and a fishy body odor.
This plant compound comes from the bark of an evergreen tree. It’s found in many weight-loss supplements, but there’s very little research on it. What’s more, it can be dangerous. Yohimbe can cause headaches, anxiety, agitation and increased blood pressure. At high doses, it can even cause heart problems and kidney failure.
Some fat burners contain ingredients high in soluble fiber. “Fiber doesn’t increase fat burn but it helps control appetite. And soluble fiber can help prevent your body from absorbing some of the fat from the foods you eat,” Matteo says. Some fiber-rich ingredients common in supplements include:
- Guar gum.
Fat burners can contain many other ingredients, too, such as:
- Conjugated linoleic acid.
- Garcinia cambogia.
- Raspberry ketones.
Many supplements contain dozens of ingredients or more, so it can be hard to say how they might affect your health.
“Weight-loss supplements contain a whole slew of herbals and other ingredients, and the dosage isn’t always listed,” Matteo says. “I would not recommend using any of these over-the-counter fat burners.”
Are fat burners safe?
Fat burners have many strikes against them. They aren’t regulated, contain questionable ingredients and aren’t likely to give you a sculpted shape. And some of them are downright dangerous.
If you’re considering these supplements, talk it over with your doctor or a pharmacist first. “Patients aren’t always forthcoming about what supplements they’re taking. But ingredients in fat burners can interact with medications and cause serious problems, so it’s important to make sure your doctor is aware,” Matteo says.
Burning fat the natural way
Instead of fat-burning supplements, Matteo recommends looking at your diet instead. “You can take a natural approach, with foods and drinks that contain substances that may promote weight loss,” she says.
Coffee and green tea
To avoid excessive doses and possible side effects, Matteo advises steering clear of supplements containing caffeine or green tea extract. Instead, enjoy a couple of cups of brewed coffee or green tea to reap the possible benefits. “Just avoid adding a lot of cream and sugar, especially if your goal is to lose weight,” she adds.
“Our bodies have to work harder to break down protein than carbohydrates or fats, so increasing protein in your diet can boost your metabolism,” Matteo says. Protein also helps control appetite.
But too much protein can lead to eating a lot more calories than you need — meaning weight gain instead of weight loss. To avoid overdoing it, Matteo suggests getting protein from your food rather than protein shakes or supplements. “Chicken, turkey, eggs and fish are great sources of lean protein,” she says.
Fiber is also a great go-to if you’re looking to lose fat. But supplements aren’t the best way to get it, Matteo says. “We digest dietary fibers best if we get them from food rather than supplements.” Luckily, there are many tasty high-fiber foods to choose from.
The bottom line
Unfortunately, there is no miracle supplement to safely melt away the pounds. “Everyone would like a quick fix. But if it sounds too good to be true, it probably is,” she adds. “When it comes to weight loss and burning fat, there’s no such thing as a magic pill.”