January is the time of year when many people try to shed holiday pounds. And the latest diet trend that claims to do that comes in a cup. It’s called the teatox.

The idea is to pair drinking certain type of teas with light eating and exercise. But does it work and is it safe? If you’re thinking of using it to shed those extra holiday pounds, Consumer Reports says detox tea might do more harm than good.

Detox teas contain a variety of ingredients including some that claim to help with weight loss, including stimulants like guarana which can contain up to four times the amount of caffeine in coffee.

“Too much caffeine will not only not help long-term with weight loss but can cause issues like jitteriness and nervousness,” explained Diane Umansky with Consumer Reports.

These teatoxes also often contain laxatives like senna or senna leaf.

“The reason you might see a short-term dip in the scale is because they’re dehydrating. But once you consume enough liquid, your weight will go right back up. And used to excess, laxatives can be dangerous,” warned Umansky.

Detox teas are considered dietary supplements and are regulated much more loosely than traditional medications. That means what’s listed on the label isn’t always reliable.

And if weight loss is your goal, there are better, safer and proven strategies.

“It’s good to keep an eye on your portions and keep those under control. Get plenty of fibre, which you’ll find in whole grains and in produce. And step up your physical activity if you’re not so active,” Umansky said.

If you’re still thinking of a teatox, talk to your doctor or pharmacist first to make sure what’s in the ingredients won’t conflict with any medication you are taking.

And if you prefer traditional tea, go ahead and enjoy a cup or two a day. It’s a reasonable part of a healthy diet and may have some small weight loss benefits.