Sure, you know that coffee comes from coffee beans. But how often do you really register that word, “beans”? That hot beverage you sip every morning is actually made from plants — and like so many plants, at one point, coffee plants were ripe, green and leafy and growing on tall shrubs. Once the beans (or seeds) from these plants are harvested and roasted, we get coffee. But what about raw, or green, coffee beans?
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Some people claim that taking supplements made of green coffee bean extract can help you lose weight, an idea that rose to popularity after it was featured on an episode of The Dr. Oz Show. But is there any truth to it?
Registered dietitian Beth Czerwony, RD, LD, says not to believe the hype. She shares the thought process behind taking green coffee bean extract for weight loss — and explains why it’s not the magic pill you’re hoping for.
Green coffee bean extract is a supplement (extract) made of coffee beans that have not yet been roasted.
“The difference between roasted and unroasted coffee beans is the presence of chlorogenic acid, which is only present in raw beans,” Czerwony explains. “Once it’s heated, that chlorogenic acid is destroyed.”
Proponents of green coffee bean extract say the chlorogenic acid is the key to health benefits. It’s a natural antioxidant, which means it can help tame inflammation in the body and may also help lower blood pressure.
“Some research says it could also help with blood sugar,” Czerwony notes, “because it decreases the amount of carbohydrates absorbed into the gastrointestinal tract. This is where people are making the correlation with some desirable weight loss.”
The main claim in favor of taking green coffee bean extract is that it can aid in weight loss. But not so fast.
“There have only been a couple of studies, and for lack of a better word, they’re kind of messy,” Czerwony says. “They're not large enough or robust enough to say whether the benefits are real.”
In a 2017 study, some participants took 400 milligrams (mg) of green coffee bean extract for eight weeks, while also following a calorie-restrictive diet; the other participants just followed a calorie-restrictive diet.
“The outcome showed that the first group of participants lost more weight, but it was only about three to five pounds,” Czerwony continues. “It wasn’t enough to be considered significant.”
The study also didn’t account for participants’ exercise habits or note whether they regained the weight they’d lost once they stopped taking the green coffee bean extract.
In short, Czerwony says, “Research is very limited. There are too many variables and no long-term studies.”
You should always speak with a healthcare provider before you start taking new-to-you supplements, including this one.
“Any time you’re thinking about adding in a supplement, it’s important to talk to your doctor first,” Czerwony advises. “You need to make sure it’s not going to interact negatively with anything you’re already taking or affect any conditions you may have.”
And if you have a caffeine sensitivity, you’re really going to want to skip green coffee bean extract. Like its more evolved friend, coffee, this supplement also contains caffeine, and it brings some of the same possible effects. Too much caffeine can cause:
Because the U.S. Food and Drug Administration (FDA) doesn’t regulate supplements, Czerwony says it’s almost impossible to know how much caffeine is really in green coffee bean extract.
“Every amount of caffeine is going to vary based on the bean,” she explains. “You could get a really high dose in one batch and then much less in another.”
Experts recommend sticking to less than 400 mg of caffeine per day — and if you’re inclined to caffeinate, Czerwony says that you’re better off getting it from a cup or two of your favorite brew than in the form of capsules.
If you’re thinking about trying green coffee bean extract (or are already taking it), Czerwony encourages you to take a pause and reframe your thinking.
“It’s important to know your ‘why,’” she says. “Ask yourself: Why am I doing this? Are you doing it for weight loss? Are you trying to get anti-inflammatory benefits? Are you taking it because your blood pressure is too high or your blood sugars are creeping up? Because there are other ways that you can do all of those things.”
Oh, yeah, and here’s another important thing to know: If you’re dead set on incorporating chlorogenic acid into your diet, there are plenty of other ways to get it … and they’re all a part of a healthy diet. You can find chlorogenic acid in foods like:
“Why risk taking in all that extra caffeine for unproven benefits?” Czerwony questions. “You can't depend on an unproven supplement to replace a healthy diet — but when you eat the rainbow, you can safely get different kinds of antioxidants.”