What is a juice cleanse?
A juice cleanse consists of consuming only juice from fruits and vegetables for a short period of time (anywhere from 2-14 days is what I have seen). It's usually promoted as a detoxification diet, or a way to eliminate toxins that have accumulated in the body, while also kick-starting weight loss. While there may be potential benefits in doing a juice cleanse, the support is mostly from anecdotal evidence (personal testimony) lacking scientific proof. You've probably seen this all over social media profiles of celebrities or so-called "health enthusiasts" posting attractive photos with hashtags like #detoxify, #cleanseyourbody, #juicecleanse, or #itreallyworks...
Juicing is different than blending because it involves the process of removing and separating the pulp (or fiber) of fruits and vegetables from the juice. Yes–this can serve as a concentrated source of vitamins/minerals and help you consume more fruits and vegetables altogether. However, by definition, you’re significantly reducing the amount of fiber you take in. Different types of fiber help promote a healthy digestive tract, regulate bowel movements, reduce cholesterol, manage blood sugar spikes, and help you feel fuller for longer. Unless you need to follow a special diet for medical reasons, fiber is generally beneficial.
Juice cleanses can lead to weight loss because you’re limiting yourself to consuming only juice. The amount of calories taken in while following this particular diet varies but it is generally much less than what you’d typically consume, so it’s no surprise you might lose weight. However, weight loss from a juice cleanse is oftentimes related to a reduction in water weight often due to the use of food or supplements with a laxative-like effect. Not only would this make it easier to re-gain weight after reintroducing real foods, but it’s risky and can cause potentially dangerous side effects including dehydration and electrolyte imbalances such as hyponatremia (low sodium level in the blood). Side effects of hyponatremia may include headaches, fatigue, weakness, dizziness or fainting, and nausea.
Moreover, very low calorie cleanses cause your body to shift into starvation mode. This may be counterproductive by causing an increase in cortisol. Often referred to as the “the stress hormone”, cortisol is released in response to stress to help your body maintain homeostasis and survive. Research suggests an increased cortisol level is likely a response to the psychological and physiological stress of dieting and calorie restriction. Increased levels of this hormone have been been associated with weight gain, partly due to its role in stimulating appetite and facilitating fat storage. Researchers have also found increased cortisol levels can persist after transitioning back to eating real foods which could make it harder to continue losing weight or keep lost weight off. (FYI: references can be found at the end of this post)
Juice cleanses and other detox diets are often promoted after a period of overeating or unwanted weight gain (after the holiday season, at the start of a new year, “summer body goals”, etc.). I advise caution as this could create unhealthy habits like using food as reward or punishment.
IMO: the potential risks outweigh the potential benefits. You don’t need a special diet to detox your body — your liver and kidneys run a tight ship to filter and eliminate toxins.
If you want to include juicing as part of your healthy lifestyle, I suggest the following:
For other resources to help you plan meals, I suggest checking out What’s Cooking? by the USDA for tools, recipes, budget tips, and more. Also, the American Institute for Cancer Research has a recipes database with everything guaranteed to fit nutrition guidelines for cancer prevention and reducing your individual risk. More on that to come!
I'm Gabbie, a registered dietitian nutritionist (RDN) based in Texas! I think eating well should be simple and enjoyable, and I love helping other busy adults feel empowered to lead healthier lives!