Chewing ice is a diet fad that has gained attention thanks to gastroenterologist Dr. Brian Weiner and his e-book, The Ice Diet. Weiner claims it is a way to snack guilt-free and burn some calories while doing so. Others disagree with the doctor’s recommendations, arguing that besides making your mouth cold and not helping very much with weight loss, chewing ice may actually be bad for your health.

According to Weiner, he came up with the diet idea when he tried to lose a few extra pounds by replacing ice cream with Italian ice. The Italian ices Weiner consumed contained about 100 calories per serving. "One evening, in a burst of insight, I realized that this calculation was incorrect. The manufacturer of the ices did not calculate the energy required to melt the ice and did not deduct this from the calorie calculation," Weiner explained to The Atlantic. In other words, Weiner believes that because the body uses energy to melt ice, ice not only contains zero calories but also helps an individual burn calories, precisely 160 calories per liter of ice consumed. Weiner delves into the details in his e-book.

The problem with Weiner’s diet is that although it is true that the body uses energy to melt ice, as Andrew Zimmerman Jones, physicist and author of the book String Theory For Dummies puts it, eating ice is “not exactly the most efficient diet plan.” According to Zimmerman, consuming a pound of ice a day would result in losing a pound of weight every two months. This little amount of actual weight loss is due to a combination of the sheer high amount of calories (3,500) that one needs to burn to lose a pound and the fact that thermal energy used to melt ice isn’t always a result of a metabolic process.

What’s even more alarming is the harm that ice has already been proved to cause, particularly to oral health. Ice is rather hard. Just ask anyone who’s fallen while attempting to skate on the substance. Bashing it around our mouth can cause tooth fractures, cracking and chipping. OUCH! Chewing ice is also known to: wear down tooth enamel, increase sensitivity to hot and cold foods, and make teeth more vulnerable to decay. Even Weiner himself warned that earting more than a liter of ice would be “toxic” and causing organs to become too cold to function, The Daily Lounge reported.

For those who have cravings to consume ice for reasons other than the Ice Diet, this may be a sign of iron deficiency, or anemia. Although the link between iron deficiency and the desire to eat ice is not fully understood, it does have a name: pagophagia. Some doctors suspect that the body unconsciously desires to eat ice to relieve the inflammation in the mouth caused by the vitamin deficiency, The New York Times reported.