More people are becoming conscious of implementing healthier choices into their everyday lives, leading them to try different diets, including fasting. A fast that has been around for some time and is gaining popularity again is juice fasting.
Also known as the “juice detox” or the “juice cleanse,” it has become a go-to solution for people to lose weight, improve their health, increase energy levels, and boost their immune system.
But is juice fasting all evidence-based and effective? We’ll discuss its benefits and risks so you can decide if it’s right for you.
What is Juice Fasting?
Juice fasting is a detoxification diet that involves consuming only juice from fruits and vegetables for a set period. Those doing a juice fast can drink homemade or premade fluids made from fruits, vegetables, herbs, and occasionally nut milk. You may drink tea, water, and sometimes clear broths while on a juice fast.
How Does Juice Fasting Work?
Juice fasting works by consuming raw, cold-pressed, organic juice. Drinking only the juice from fruits and vegetables and clearing the diet of refined foods, sugar, and caffeine is said to aid in the body’s natural detoxification process.
Juice Fasting Benefits
Here are some of the benefits of juice fasting supported by studies:
- Increased nutrients: Adults are often recommended to consume at least five servings of fruits and vegetables daily for a healthy diet (*). However, many people do not adhere to this due to the practicalities, inconvenience, and effort required to eat whole fruits and vegetables. A review posits that fruit juice is an excellent alternative since it allows people to consume fruits and vegetables more easily, providing them with more nutrients such as vitamin C, carotenoids, and polyphenols, which offer many health-related benefits (*).
- Improved gut health: The balance of bacteria inside the gut is essential for good health. A 2017 study found that a juice-based diet helped alter the gut microbiome due to a higher intake of vitamins, minerals, and anti-inflammatory compounds. Participants in the study were found to have altered intestinal microorganisms associated with weight loss following a three-day juice cleanse (*). They also rated their well-being as higher after the juice fast.
- Better cardiovascular health: Drinking vegetable and fruit juices is also associated with lowering blood pressure and improving blood lipid profiles, according to further research summarizing several recent studies (*). This led to anti-inflammatory effects and improvements in some aspects of the cardiovascular system.
- Elimination of toxins: Various fruits and vegetables are recognized as natural assistants in the detoxification process. Specifically, cruciferous vegetables and berries were found to be involved in the transformation and elimination of toxins in the body (*).
- Weight loss: In the same 2017 study mentioned above, the 20 healthy participants who consumed only juices for three days lost an average of 1.7 kilograms (*). During a follow-up two weeks later, their weight was still 0.91 kilograms lower on average.
Risks of Juice Fasting
While juice fasting has many benefits, certain risks should also be considered:
- Hunger: Juice fasting can lead to feelings of hunger since the body is accustomed to consuming solid food daily.
- Temporary weight loss: A review conducted in 2017 found that juicing and other detoxification diets achieved the desired weight-loss result by restricting caloric intake during the fast. However, weight gain occurs once the fasting individual’s normal diet is resumed (*).
- Increased sugar intake: Most fruit juices have a high sugar content, which is why some studies recommend the consumption of real fruit to combat diabetes instead of juice (*). Juice fasts can lead to increased sugar intake, which is why it is important to mix juiced fruit with an appropriate dose of vegetables to avoid too much sugar.
- Headaches and fatigue: Since most people are used to eating solid foods daily, going on a juice fast may cause symptoms such as headache and fatigue. This can be due to fluctuating blood sugar and a lack of fat and protein intake during the juice fast.
Types of Juices Used in Juice Fasting
There are several types of juice used in juice fasting, including fruit, green, and protein-based juices:
- Fruit juices consist primarily of juice from fruits, such as berries, oranges, and grapefruit.
- Green juices use green vegetables (spinach and kale are two popular options) along with other ingredients, such as ginger and apples.
- Protein-based juices use almond and other nut milk or pea protein powder.
Each type of juice offers different benefits, and the type of juice you choose when you fast depends on your individual needs and preferences.
For instance, green juices may be better for individuals who are looking to detox while increasing their intake of vegetables. Meanwhile, protein-based juice cleanses are more suitable for people trying to build muscle or maintain their protein intake even while on a cleanse.
How Long Should a Juice Fast Last?
A juice fast typically lasts for one day to ten days. It is typically preceded by the preparation stage, which takes three to five days, and the post-fast stage, usually two to three days.
How to Juice Fast Safely
Given its benefits and risks, juice fasting should be done safely. Here’s how:
- Drink enough juice daily: Drink at least six 16-ounce servings of juice daily to ensure you get enough calories to meet your body’s basic energy requirements. You can also drink as much water and tea as you want throughout the day.
- Add more vegetables: Make your juices mostly vegetables. Try greens like kale, spinach, cucumber, zucchini, and other low glycemic index vegetables. You can also aim for fruits with a lower sugar content and loaded with anti-inflammatory antioxidants, such as blackberries, blueberries, strawberries, lemons, and limes.
- Add fat and protein sources: If you find yourself getting hungry during the juice fast, consider adding some coconut milk or nut milk (almond milk or pistachio milk) to your juices.
- Avoid intense physical activity: Avoid strenuous physical activity such as HIIT workouts and other intense exercises to avoid becoming dizzy and fatigued.
Is Juice Fasting Safe for Everyone?
No, juice fasting is not suitable for everyone. It is generally recommended that young children, pregnant women, older adults, and those with blood sugar-related conditions avoid juice fasting.
There are also bigger health concerns for individuals with kidney issues. Many green juices have high levels of oxalate (*), which the kidneys are responsible for removing. Individuals with kidney issues should avoid juice fasting.
Frequently Asked Questions
Can I still consume water during a juice fast?
Yes, it is highly recommended to keep your body well-hydrated during the juice fast. You can try drinking lemon water to stave off hunger between juices.
Can I exercise while on a juice fast?
Yes, you can exercise during a juice fast. Remember to keep the activity light to avoid burning out or experiencing symptoms such as dizziness and fatigue.
Can I continue taking medications while on a juice fast?
Yes, you can continue taking medications while on a juice fast. If you take prescription medication, then it is best to consult with your physician before starting a juice fast.
The Bottom Line
Going on a juice detoxification diet can be beneficial in that it promotes some health benefits, such as improved gut and cardiovascular health as well as increased nutrition intake.
However, it should not be a substitute for consuming whole foods. It can be a good way to kickstart your weight loss goals, but it should not be used as a long-term method for losing weight, especially for improving your health.
By learning some of the benefits and risks, you’ll know whether going on a juice fast is right for you and how to do it safely. There is still much information to be gained about juice fast detoxification diets through research.