What you need to know about juice diets

January 9, 2020


When the new year starts and healthy living is top of mind, it’s easy to get caught up in fad diets and so-called “juice cleanses.” But what do these “detoxifying” juice diets do to your body? Are they safe? Are there benefits to juicing—and what are the risks?

To juice or not to juice

Maren Stein, MS, RD, is a clinical dietitian at Adventist Health Simi Valley and she’s here to answer all our questions about juice diets.

Is it actually good for your body to stop eating solid food and drink juice instead?

Our bodies are meant to break down food for digestive purposes, first through the action of chewing, then through the digestion and absorption of our nutrients. While we can still get some nutrients through juices, this diet is low in fiber, protein and fat, which are essential for our diets.

Who should and shouldn't juice?

Juicing, in the sense of only drinking juices and nothing else, is not a very sustainable way of eating—so I don’t believe that anyone should follow this kind of diet. But people with diabetes should be especially careful of this diet since it can raise blood sugar without having the benefit of fiber, protein and fat to slow down digestion of glucose.

What health benefits come from juicing?

While increasing fruit and vegetable intake can be beneficial if someone doesn’t usually consume those foods, juicing is not the optimal way to eat fruits and vegetables because of the lack of fiber, protein and fat in this diet.

In addition, there’s no scientific evidence to the claims that juicing can help detoxify the body or increase energy. It can lead to weight loss, but this is mostly due to an inadequate amount of calories. Once solid food is introduced back into the diet, the weight that was lost would most likely be regained.

What health risks come from juicing?

Juicing can lead to low intake of two major macronutrients: protein and fat. Protein is made of amino acids, which are the building blocks of our bodies and maintain everything from hair, nails, collagen in our skin and muscle mass—among many other things. Fat is a key part of any diet because it helps the body absorb fat-soluble vitamins A, D, E and K. Without fat, you can’t absorb those vitamins, leading to nutritional deficiencies.

Also, fiber is lacking on this diet, which is important to help stabilize blood sugar, lower cholesterol and keep the digestive system working properly. So just drinking juices without eating any solid food can cause digestive issues for the body.

What consequences are there to such a restrictive diet like juicing?

Other than what I already mentioned, being on any restrictive diet can lead to a cycle of restriction, followed by obsessing about the restricted foods, overeating or bingeing, then feeling guilty about having that food, then restricting again.

This can lead to a cycle of weight loss and weight gain, which research shows is harmful to our overall health. It is more beneficial to follow an eating pattern that contains a variety of fruits and vegetables, healthy fats such as avocado and olive oil, lean protein from plant and animal sources, and starches and grains. This eating pattern is most likely to be sustainable over a longer period of time.

Got more questions?

Many of us may need help figuring out what and how much food to put on our plates. A registered dietitian can help. Learn more about what a registered dietician can do for you.