Are juice cleanses good for you and help you lose weight?

Last Updated : 03 July 2025

Key takeaways

• The term “detox” sounds scientific, but most juice cleanses don’t explain what toxins they’re removing or how they do it. Juice cleanses aren’t scientifically proven to improve health.
• Whilst the so called “detoxifying diets” may be an effective method for short-term weight loss, this is simply due to a caloric restriction. Any weight lost is likely to come straight back upon returning to previous dietary habits.
• Significant caloric restriction and elimination of foods in juice cleansing diets can be dangerous as such diets don’t provide a sufficient energy intake or the nutrients required for general health and well-being, potentially impairing physical and mental health.
• Juice-only diets eliminate essential nutrients like protein, healthy fats, and fibre, increasing the risk of adverse effects like fatigue, muscle loss, and nutrient deficiencies.
• Sustainable, gradual lifestyle changes (including being physically active) are far more effective and safer for long-term health and weight management than quick-fix diets.

Juice cleanses are often marketed as a quick fix to drop weight, flush out toxins, and give your body a “reset.” You’ve probably seen influencers or celebrities sipping colourful juices and promising results in just a few days. It sounds tempting – but do these claims hold up? We’ll start with the facts, then look at the myth, and finally explain why the myth doesn’t hold up.

Fact: your body doesn’t need juice cleanses and they’re not a healthy way to lose weight.

The most effective diets for health and weight loss are balanced, incorporating a variety of food groups, not relying on fruit and vegetable juices only. Research consistently shows that diets rich in a variety of fruits and vegetables (minimum 400 g/day), legumes, nuts and seeds, and whole grains help lower the risk of chronic disease while also promoting healthy weight control. At the same time, it’s important to limit added and free sugars, total fats to below 30% of total daily calories, saturated fats to under 10%, and salt intake to no more than 5 g per day.¹

Juice cleanses, especially those based on fruit juice, are often high in free sugars. This goes against dietary guidelines, which recommend limiting added and free sugars for better health.

Although it’s great that some of these juice cleansing diets promote eating lots of fruits and vegetables, individually, no fruit or vegetable can provide us with all the nutrients we need to maintain optimal health. In other words, eating one type of fruit or vegetable cannot provide us with all the nutrients that we need.

Compared to whole fruits and vegetables, juicing removes most of the insoluble fibre, which may diminish their health benefits.² Drinking only juices also removes essential nutrients from your diet, such as proteins and fats, which are crucial for maintaining overall health. Proteins are necessary for muscle repair and growth, fats are vital for hormone production and brain health, and fibre aids in digestion and keeps you feeling full, amongst other functions.

Additionally, juice-only diets often lack critical vitamins and minerals like vitamin B12, (haem) iron, calcium, and zinc, which are predominantly found in animal-based foods, dairy, or fortified products. These nutrients are essential for energy production, bone health, and immune function. As a result of drinking only juices, you may experience muscle loss, fatigue, weakened immunity, and digestive issues. Also, when your body is deprived of these key nutrients, it becomes more susceptible to infections and illnesses.

Juice cleanses often fail to provide sufficient energy and can lead to extreme caloric deficits. This can make it harder to maintain weight loss in the long term. Additionally, the lack of solid food can lead to feelings of hunger and irritability, making it challenging to stick to the cleanse.

Myth: juice cleanses help you lose weight and “detox” your body.

There is no evidence for the effectiveness of “detox diet” on weight loss or toxin elimination.³ The human body already has a powerful built-in detox system: your liver, kidneys, lungs and digestive system work around the clock to eliminate waste products and harmful substances. The skin can also eliminate waste products through sweat. There is no scientific evidence that special diets or “detox” products are needed to support this process in healthy individuals. The EU has also refused authorisation of detoxification health claims for multiple foods or ingredients due to the lack of evidence.⁴

Most juice cleanses only lead to temporary weight loss. That’s because they’re often extremely low in calories, protein, and fibre. Several juice cleansing programs recommend drinking only juice for 10-21 days, often amounting to below 1000 kcal per day.³ This is well below the recommended daily energy intake for adults in Europe, which the European Food Safety Authority (EFSA) sets at around 2000 kcal/day for women and 2500 kcal/day for men.⁵ Experts recommend that an appropriate caloric deficit for weight loss is approximately 500-750 kcal per day.⁶ Going well below this, like during juice cleanses, without medical supervision can lead to fatigue, headaches, muscle loss, nutrient deficiencies, and other adverse effects. A high risk of binge eating has also been reported.⁷ Juice cleanses may also have a harmful effect on the gut microbiota due to the low fibre intake.²

Fallacy: misleading simplicity and appeal to “natural detox”

One of the appeals of juice cleanses lies in its simplicity and promise of fast results. It presents weight loss as something that can be done quickly and easily – drink juice, lose weight. But the body doesn’t work that way. When you start a crash diet or extreme fast, you often see the number on the scale drop quickly, but most of that early weight loss isn’t body fat – it’s water and glycogen, the stores form of carbohydrate in your muscles and liver. Each gram of glycogen is stores with approximately 3 grams of water, so when your body taps into these reserves for energy, it also sheds that water, causing a rapid but temporary drop in weight. However, this isn’t the same as fat loss and after a few weeks weight loss will plateau. When you start eating normally again, the weight usually comes back.⁸Only when the glycogen stores are used up, does weight loss slow down and you begin losing fat at a more gradual, sustainable pace. Shortcuts to weight loss, like juice cleanses, usually come with a cost such as nutrient deficiencies and yo-yo weight regain. There are many alternative diets that provide sufficient protein and micronutrients while also promoting weight loss, such as the Mediterranean diet, which has been shown to benefit both weight management and overall health.⁹

Another fallacy is that the term "detox" sounds scientific, but most juice cleanses don’t explain what toxins they’re removing or how they do it.⁷ This vagueness makes “detox” diets seem appealing by allowing broad and unverified claims about their benefits. Promoting juice cleanses as “detoxification” methods can further mislead people into thinking they’re scientifically proven ways to improve health. Imagine feeling excited about a new juice cleanse – only to find yourself after a few days fatigued, battling constant headaches, feeling nauseous after every sip, struggling to fall asleep at night, gripped by sudden waves of anxiety, and dealing with shakiness that makes even simple tasks feel overwhelming.³ Companies often claim these symptoms are due to “bad stuff leaving the body.” However, this explanation distracts from the real cause, which is often the restrictive nature of the cleanse and lack of essential nutrients.

Another common technique used to promote juice cleanses is celebrity endorsements. Companies that sell juice cleanses often showcase fit and glamorous celebrities or influencers who claim that their health, glowing skin, or slim figures are thanks to juice cleanses. This creates the illusion that simply drinking these juices will lead to similar results for anyone. However, what these promotions rarely mention is that celebrities often have access to personal trainers, private chefs, nutritionists, and cosmetic treatments – all of which play a major role in their appearance. Many of these endorsements are also paid partnerships. Someone who is trying to sell you something may present biased or exaggerated information, which is not necessarily based on scientific evidence. Relying on these endorsements can lead to unrealistic expectations and disappointment.