Promising the Moon: The Truth Behind the Werewolf Diet

Unlike the Paleo diet, which encourages you to eat like a cave man, the so-called Werewolf Diet doesn’t actually involve having the bloodlust of werewolves. But it is based on the cycles of the moon, and it’s the latest eating craze among some celebrities.

The idea is that the moon influences the water in our bodies in the same way that it impacts the tides of the ocean. According to the website Moon Connection, humans are made up of a lot of water (which is true), and when the moon is full or at a new phase, there’s a gravitational pull that can last for 24 hours and affect how much water weight you can gain or lose (questionable). Dieters can follow two plans, the basic moon diet plan and the extended version. The basic version is a 24-hour day of fasting in which you only drink water and juice during the full moon or new moon. That supposedly cleanses your body of toxins, and the website says you can lose up to six pounds of water weight that day (highly unlikely).

(MORE: For Successful Weight Loss, Forget Fad Diets and Pills)

The extended version starts with fasting at the full moon and then follows with specific eating plans for the various phases of the moon: full moon, waning moon, new moon, and waxing moon. For example, during the waxing moon, you’re supposed to eat less. ” You don’t have to starve yourself, but you need to be sure to stop eating your meals as soon as you begin to feel full—don’t overeat and don’t give in to cravings! Especially avoid thickeners (sweets, fats, etc.) in this phase,” the site recommends. (Sounds familiar, doesn’t it?) During the waning moon dieters are told not to eat after 6 p.m. when moon light starts to become visible.

While the solid foods the diet recommends — like vegetable soups and other veggies — aren’t so over the moon, most websites promoting the diet warn that it’s not safe to stay on the diet for more than six days. Technically, some juice cleanse diets are similar, but those also raise concerns among nutritionists. They say there is no solid evidence that anyone can lose six pounds in a day. Some people on juice cleanses report some slight weight loss, but that’s typically water weight that will pack back on once the dieter eats solid foods again.

Eating based on the phases of the moon is simply not sustainable, and could border on being unhealthy, say experts. “This diet makes me laugh. I don’t know if it’s the name or that people will actually believe it. Either way, it is nothing but another fad diet encouraging restriction. Restriction of food will of course lead to weight loss, but at what cost to the rest of your body?” says Keri Gans, a registered dietitian and author of The Small Change Diet. “If only celebrities, once and for all, would start touting a diet plan that makes sense and is based on science.”