Almost everyone’s serving a new diet nowadays. As a result, it can be hard to keep track of what’s an unhealthy fad versus sound nutritional advice. But knowing the difference can be vital in helping patients nourish their bodies in healthy ways—and gain, lose, or maintain necessary weight.

One of these trending diets is the “One Meal A Day” diet, also known as OMAD. Like its name implies, OMAD involves eating a single meal—and nothing else—each day. Dietitians have different takes on the safety and effectiveness of the diet, but what they seem to agree on is that it’s not one-size-fits-all.

OMAD diet and weight loss

The OMAD diet promotes weight loss primarily through calorie restriction. With one meal a day, people have limited time and space to consume their daily calories. This can lead to weight loss for some people, but whether or not it leads to healthy weight loss isn’t so definitive.

While some studies have found eating one meal a day to promote weight loss and reduced body fat, studies have also found the diet can induce higher blood pressure, higher HDL and LDL cholesterol, increased hunger, and decreased fullness, among other negative impacts. Researchers also note that more research is needed to confirm the positive or negative impacts of extreme fasting.