At a time when Kim Kardashian is promoting appetite-suppressing lollipops, and everyone is quitting sugar to get healthier, most quick-fix diet trends or fads probably give you some pause. For example, if you hear that there's an ancient plant that can get rid of your cravings for sweet foods and therefore get you to stop eating sugar, some alarms should go off.
Shockingly, this herb is a real thing, and it's called gymnema sylvestre. Found growing in tropical regions, gymnema sylvestre leaves have been used in Ayurvedic medicine since the 1930s to treat diabetes by controlling blood sugar. However, recently the herb has been marketed as a supplement for people who are looking to eat less sugar. But is that a good thing?
To answer this question, you have to understand how gymnema sylvestre works, and it's kind of complicated. Researchers have shown that gymnema sylvestre bonds to specific receptors located on the tongue's taste buds, which block sugar from activating them. "So, it actually bonds to these receptors and you get signals to your brain that say, Oh, I don't like that. I don't want or desire the taste and sweetness," says Fatima Cody Stanford, MD, MPH, an obesity medicine physician at Massachusetts General Hospital. "It changes the taste of something you consume." This effect could last for a few hours after you consume gymnema sylvestre, and then it goes away, she says.
In addition to altering the way you taste sweet things, gymnema sylvestre also appears to allow more insulin to be secreted from the pancreas, which could be good for people with moderately high blood sugar levels, Dr. Stanford says. Insulin drives blood sugar down, so it could end up being useful for people with type 2 diabetes or pre-diabetes once researchers nail down a safe dose and concentration, she says. But you really shouldn't mess around with gymnema sylvestre (or any "herbal" or "natural" supplement) unless your doctor has okayed it.
We've kind of labeled sugar as the evil Satan, and everything is bad about it. But the body does crave sugar when it needs sugar.
Fatima Cody Stanford, MD, MPH, an obesity medicine physician at Massachusetts General Hospital
Now, you can probably tell how this herb would be appealing to people who simply have a preference for sweet items and want to avoid them or quit sugar altogether — and this is where it gets tricky. "We as a population in the U.S. tend to believe that if we curb sugar cravings, we've solved obesity and diabetes," Dr. Stanford says. "And I think that’s an oversimplification of the problem." Sure, sugar may play a role for some individuals, but giving up sugar isn't the answer to everyone's problems. "We've kind of labeled sugar as the evil Satan, and everything is bad about it. But the body does crave sugar when it needs sugar," she says. There are purer sources of sugar (fruit versus candy, for example), which may be healthier, but all sugar is not bad.
Also, the whole idea that you need to "curb" cravings at all is flawed. We know based on research that when you try to avoid or restrict a food it can lead to overeating and binging. What's more important is listening to your cravings and paying attention to when you feel full. "If you feel hungry all the time, or take a long time to feel full, you might do a thorough investigation about what things are causing that for you," Dr. Stanford says. It could be that your diet is lacking in fiber or protein, which isn't good either. And remember that everyone is different, so just because something like gymnema sylvestre works for one person, doesn't necessarily mean it's right for you.
So basically, gymnema sylvestre seems like it could be promising for some people, but it's "not ready for prime time," Dr. Stanford says. There's no standardized dose, and the Food and Drug Administration currently doesn't regulate these types of natural agents, so you have to be super cautious, and definitely tell your doctor before taking anything, she says. There could be side effects to gymnema sylvestre that we don't know about yet (there has been a case of a patient with diabetes getting toxic hepatitis from gymnema sylvestre), or it could interact with medications that you take — even though it is just a plant. "People like the word natural, but 'natural agents' doesn't always mean good," she says.