Juice fasting or water fasting?
|
|
Time to read 6 min
Introduction
Juice fasting or water fasting, which form is right for you? Both involve going without solid food for a few days, yet they are worlds apart. With one, you only drink water and tea; with the other, you get some energy from juices. This changes how the days feel and how much support you need.
When looking at juice fasting versus water fasting, we consider energy, muscles, safety, and daily life. You will learn about the strengths and weaknesses of both forms and which one we recommend for getting started.
Good to know
With water fasting, you consume no calories. Classic therapeutic fasting according to Buchinger ranges from 250 to 500 kilocalories per day. A juice cleanse like the BESSERE SAFTKUR PLUS provides 731 to 885 calories, according to nutritional information.
Juice fasting or water fasting? The short answer
For most healthy people, juice fasting is the easier way to start. You get some energy, vitamins, and fluids, and you can fit the cleanse into a calm daily routine. Water fasting is the strictest form of fasting. Because of the risks, it should be done under medical supervision and fits better into a clinic stay than a normal work week. So, when it comes to juice fasting or water fasting, it is less about which is better or worse; it is about the framework and the experience.
In between lies therapeutic fasting according to Buchinger with juice, broth, and a little honey. The Medical Association for Fasting and Nutrition (ÄGHE) recommends a maximum of about 500 kilocalories per day for this (ÄGHE, 2025).
| Feature | Juice Fasting | Water Fasting |
|---|---|---|
| Daily energy | approx. 500 to 900 kilocalories | none |
| What you drink | vegetable and fruit juices, water, tea | only water and unsweetened tea |
| Support | possible alone for healthy individuals; medical supervision for pre-existing conditions | medical supervision recommended |
| Daily life | calm days are sufficient | rest or clinic |
| Typical duration | three to seven days | several days under supervision |
| For whom | beginners and experienced | experienced individuals with support |
What matters in the comparison
Energy and nutrients
The clearest difference is energy. During water fasting, your body relies entirely on its reserves. In the first 24 to 48 hours, it depletes glycogen stores, after which it shifts more strongly to fat reserves (Swiss medical journal, 2022). With juice fasting, you get some sugar from the juices throughout the day, plus vitamins and minerals. This makes the transition smoother. The German Nutrition Society (DGE) sees exactly this as the difference. In therapeutic fasting, the body still receives a little energy, while in total fasting, it receives none (DGE, 2018).
Our preliminary assessment 👈
If you are fasting for the first time, do a three-day juice fast. Water fasting is not for beginners, but for experienced individuals with medical supervision.
Muscles and protein
When it comes to juice fasting or water fasting, this is a point that many comparisons omit. Anyone who eats nothing loses more than just fat. A 2024 review evaluated eight studies on prolonged water fasting. About two-thirds of the weight lost was water and muscle, with only one-third being fat (Ezpeleta et al., 2024). At the beginning of a total fast, the body breaks down up to 75 grams of protein per day (Swiss medical journal, 2022). There is hardly any data on this for juice cleanses. This is another reason why short cleanses are the safe choice.
Support and safety
The same paper mentions common complaints during water fasting, such as poor sleep, fatigue, dizziness, dry mouth, and headaches. Serious consequences, such as acidic blood or fluid retention, were rare (Ezpeleta et al., 2024). A large study of 1,422 fasting participants shows how much support matters. They were monitored by doctors daily and received 200 to 250 kilocalories per day. Serious side effects occurred in less than one percent (Wilhelmi de Toledo et al., 2019). That is why water fasting belongs in experienced hands. Limits also apply to juice fasting. Pregnancy, breastfeeding, being underweight, eating disorders, and severe liver or kidney disease exclude anyone from fasting (ÄGHE, 2025). Anyone taking medication should never fast alone. You can find the exact checklist in our article on who a juice cleanse is suitable for.
Both forms in direct comparison
Water fasting: advantages and disadvantages
Anyone weighing up juice fasting or water fasting should know the stricter form well. Water fasting is the oldest and strictest form of fasting. You drink only water and unsweetened herbal tea and consume no calories. In clinics, it is performed under medical supervision with regular checks. The appeal lies in the simplicity; the price is the burden on the body.
Advantages:
- Maximum simplicity: You need nothing but water and tea.
- No calories: Weight drops faster in the first few days than with any other form.
- Clear rules: There is no question about what you are allowed to drink.
- Well researched: There are more studies on supervised fasting than on juice cleanses.
Disadvantages:
- Significant muscle loss: About two-thirds of the weight you lose is water and muscle.
- Common complaints: Dizziness, fatigue, and poor sleep are often present.
- Requires support: It is not advisable for many without medical supervision.
- Hardly suitable for daily life: Work and appointments do not mix well with zero calories.
Juice Fasting: Pros and Cons
During a juice fast, you drink several juices throughout the day, along with water and tea. Whether a juice fast or water fast feels easier usually becomes apparent on the second day, where a juice cleanse has a clear advantage. However, there is a catch you should be aware of: juices contain sugar and hardly any fiber. A small study found changes in oral and gut flora after three days of juice-only consumption. Researchers identified sugar and a lack of fiber as the causes (US study, 2025). This makes a strong case for short, vegetable-based cleanses.
Pros:
- Gentler start: A bit of energy makes the first few days significantly easier.
- Vitamins and hydration: Vegetable juices provide vitamins that are lacking in water fasting.
- Suitable for daily life: You can continue to work normally on quieter days.
- Doable alone: No clinic is necessary for healthy adults without pre-existing conditions.
Cons:
- Sugar in a glass: Fruit-heavy juices deliver a lot of fructose, so vegetables are a must.
- Hardly any fiber: It stays behind in the pulp during pressing.
- Less research: There is significantly less research on juice cleanses than on supervised fasting.
- No shortcut: A portion of the weight often returns after the cleanse here as well.
Our article on calories and sugar in a juice cleanse shows how much sugar is in each juice.
Juice Fasting vs. Water Fasting in a Nutshell
Water fasting is the strictest form and requires medical supervision.
Around two-thirds of the weight lost during water fasting is water and muscle mass.
Juice fasting is gentler and fits into quieter days.
With juice fasting, the vegetable content determines the sugar level.
For beginners, a vegetable-focused three-day juice cleanse is ideal.
What is the difference between juice fasting and water fasting?
During water fasting, you only consume water and tea with zero caloric intake. Juice fasting involves adding juices, which provide some energy, vitamins, and minerals.
Which is better, juice fasting or water fasting?
For beginners, juice fasting is usually the better choice because it is gentler and easier to integrate into daily life. Water fasting is more restrictive and should be done under medical supervision.
Do you lose muscle during water fasting?
Yes. Studies on prolonged water fasting show that about two-thirds of the weight lost consisted of water and muscle.
Do you lose weight faster with water fasting?
In the short term, yes, because no calories are being consumed. However, a large part of this is water and muscle mass, and without lifestyle changes afterwards, the weight often returns.
Can I do water fasting on my own?
This is not advisable for many people. Water fasting should be done under medical supervision, especially if you take medication or have pre-existing conditions.
Is juice fasting too sweet?
That depends on the juices. Fruit-heavy cleanses provide a lot of fructose, while vegetable-focused ones contain significantly less. Always check the ingredients list.
Who should not fast at all?
Fasting is not suitable during pregnancy or breastfeeding, or for those with underweight, eating disorders, or severe liver or kidney disease.
The author: David J Kugler
Founder and Managing Director of DALUMA. Writes about nutrition, juice cleanses, and holistic self-care.
