Can you go into ketosis on a juice cleanse?

Introduction

A juice cleanse is a type of diet that involves consuming only fresh fruit and vegetable juices for a set period of time, usually lasting anywhere from 3-10 days. Some people follow juice cleanses in an attempt to lose weight quickly or flush out toxins. Since juice cleanses are very low in calories and carbohydrates, some have claimed they can induce ketosis – the metabolic state where your body burns fat for fuel instead of carbs. But is this really the case? Let’s take a closer look at how juice cleanses work and whether they can actually cause ketosis.

What is Ketosis?

Ketosis is a natural metabolic state marked by higher-than-normal levels of ketones in the blood. Ketones are produced by the liver from fat when glucose levels are low. This occurs most often when carbohydrate intake is extremely low, such as when fasting or following a ketogenic diet.

During ketosis, the body adapts to using fat and ketones rather than glucose for fuel. This causes fat stores to be broken down, leading to weight loss. Ketosis may also have other health benefits, such as reducing seizures in people with epilepsy.

Ketosis is typically defined as having blood ketone levels above 0.5 mmol/L. Levels of 1.5-3 mmol/L indicate nutritional ketosis, which is considered safe for most people. Higher levels may occur in uncontrolled diabetes (ketoacidosis).

Ketosis occurs when:

• Carbohydrate intake is below 50 grams per day
• Protein intake is moderate
• Fat intake makes up the majority of calories

This extremely low carb, high fat intake “forces” the body to burn fats and enter ketosis.

Can a Juice Cleanse Induce Ketosis?

To induce ketosis, carbohydrate intake needs to be kept very low, generally under 50 grams per day. Most fresh fruit and vegetable juices contain significant amounts of carbs:

Juice	Carbs per 8 oz
Orange juice	21 grams
Apple juice	28 grams
Carrot juice	16 grams
Beet juice	18 grams

As you can see, even 8 oz of these common juices provides anywhere from 16-28 grams of carbs. Over the course of a full day on a juice cleanse, it would be very difficult to keep net carbs under 50 grams unless you strategically choose low sugar vegetables and avoid all fruits.

Some people have claimed that juice cleanses induce ketosis by lowering overall calorie intake. While severe calorie restriction does lead to some metabolic adaptations like reduced insulin, this alone does not induce nutritional ketosis.

The body’s main fuel source will still be glucose from the carbohydrates consumed. Ketone production remains low and fat burning will be limited on a juice cleanse.

Other Concerns with Juice Cleanses

In addition to being unable to induce ketosis, juice cleanses come with some other potential downsides:

• Loss of muscle mass – Lack of protein intake causes muscle breakdown.
• Extreme hunger – Juices are low in fiber and protein which provide satiety.
• Nutrient deficiencies – Long-term restrictions lead to vitamin, mineral and electrolyte imbalances.
• Yo-yo dieting – Any weight lost is often rapidly regained after the cleanse.

For these reasons, most health authorities do not recommend juice cleanses and consider them a fad diet without long-term benefits.

Safe Ways to Achieve Ketosis

While juice cleanses may sound appealing for fast weight loss, they should be avoided. There are safer, more effective ways to get into ketosis:

• Ketogenic diet – Very low carb (under 50g), high fat, adequate protein.
• Intermittent fasting – Alternating fasting and eating windows throughout the week.
• Extended fasting – Going without food for 24-48 hours. Should be done cautiously.

The key is limiting carbohydrates consistently, not extremely restricting calories or avoiding whole foods. A well-formulated ketogenic diet tailored to your needs is ideal for long-lasting nutritional ketosis.

The Bottom Line

While juice cleanses may sound tempting, they are unlikely to induce ketosis due to their high carbohydrate content. They come with health risks and should be avoided. Sticking to a proper ketogenic diet with whole foods is the best approach.

If your goal is ketosis for health and weight loss, focus on limiting carbohydrates to under 50g per day while keeping protein and fat intake adequate. This safe nutritional approach will get you into ketosis without the drawbacks of a juice cleanse.

References

1. Volek, J. S., & Phinney, S. D. (2011). The art and science of low carbohydrate living: an expert guide to making the life-saving benefits of carbohydrate restriction sustainable and enjoyable. Beyond Obesity, LLC.
2. Paoli, A. (2014). Ketogenic diet for obesity: friend or foe?. International journal of environmental research and public health, 11(2), 2092–2107. https://doi.org/10.3390/ijerph110202092
3. Kossoff, E. H. (2014). The ketogenic and Atkins diets: recipes for seizure control. Practical gastroenterology, 38(6), 32–41.
4. USDA FoodData Central. https://fdc.nal.usda.gov/
5. Harvard T.H. Chan School of Public Health. The Truth About Juice Cleanses. https://www.hsph.harvard.edu/nutritionsource/healthy-drinks/juice/