Fasting has become a popular way to lose weight, and there are many other benefits of the practice (when done right) including things like lower blood-sugar levels, lowered cholesterol, and increased cognitive function. But a trend called "dry fasting" has emerged that has health experts concerned.
Typically, fasting is defined as willingly going for a period of time without consuming any food. Intermittent fasting involves cycling between eating and not eating over a 24 hour period — for example, eating for eight hours of the day and fasting for the other 16. Another method of fasting is called alternate-day fasting, which means eating on one day and then fasting for the next. Fasting practices don’t typically restrict water, but encourage drinking H20 to help stimulate digestion and the elimination of toxins.
Dry fasting, which calls for going without both food and water, is a whole different ball game. Some influencers and health bloggers are claiming that dry fasting has even more benefits like improved skin conditions, better immunity, and more weight loss. However, since there haven’t been studies on fasting without any water or liquids, there is no evidence of that.
Experts are also warning about the side effects of dry-fasting. Dr. Pauline Yi, a physician at UCLA, told the LA Times that dry fasting is dangerous because when your body isn’t getting energy from calories, it begins to break down muscles and fat. When muscle and fat cells get broken down, toxic byproducts are released that require water to flush them out of the body. That means that if you’re already not eating food, your body needs more water — not less. She also states that when the body isn’t getting water, it automatically shifts to retaining water. “Your body likes homeostasis,” said Yi. “If you’re going to cut back on water, your body will produce hormones and chemicals to hold onto any water.” That’s not good.
Some side effects of dry fasting that may not be so harmful in the long term, like tiredness, hunger, irritability, poor focus, and decreased urination. But more serious side effects like dehydration, nutrient deficiencies, urinary problems, and kidney issues could have long-term health consequences.
Valter Longo, who has studied fasting, caloric restriction, and starvation in humans for nearly 30 years and developed the Fasting Mimicking Diet, also told the LA Times, “For sure, the body needs to reset, but there are safe ways of doing that, and dry fasting is not one of them. We require water.”
Though people are claiming that there are benefits of going long periods without water, we’ll go ahead and take it from the experts: This practice seems dangerous and is probably best avoided. For alternative ways to fast safely, check out this article on time-restricted feeding that has some actual, proven health benefits for more than just your waistline.
This content is not a substitute for professional medical advice or diagnosis. Always consult your physician before pursuing any treatment plan.