Detox Diets and Juice Cleanses

What is a detox/cleanse diet?

Cleanse diets can consist of a variety of dietary or lifestyle regimens such as fasting, food restrictions, liquid only consumption, use of enemas or laxatives, or a combination of these approaches. These diets generally last multiple days and are intended to rid the body of toxins, and/or support weight loss. Given the popularity of liquid only diets, also known as juice cleanses, it’s important to be aware of the potential health implications of these diets.

Why would someone start a juice cleanse?

Juice cleanse companies and advocates have claimed a multitude of health benefits from juice cleanses. Some say it is an effective weight loss method, allows you to experience more powerful workouts, boosts your immune system, provides immediate nutrient absorption, and increased energy. They also claim that completing a juice cleanse allows your body the time to heal its digestive tract and detoxify itself.

Are all these claims true?

The quick answer is no. There is no convincing scientific evidence that juice cleanse diets improve overall health. Why not?

Weight loss & detox diets:

When it comes to weight loss, these diets may be effective in producing quick results, however, sustained weight loss is unlikely given the restrictive nature of a juice cleanse. Weight loss may be attributed to the sheer lack of calories provided by juices. It’s important to note that such low caloric intake can result in fatigue, faintness, headache, and difficulty concentrating.

Powerful workouts:

Along with weight loss, juice cleanse companies claim that this regime will allow you to experience more powerful workouts. This would be unlikely given the effects a low-calorie diet like a juice cleanse would have on the body. Completing an effective workout while already tired and lacking energy is extremely difficult and likely ineffective. Additionally, it’s important to consume a well-balanced meal with carbohydrates and protein after a workout to re-fill the body’s energy stores and promote muscle repair. Juice cleanses generally consist only of fruit and vegetable juices, meaning protein consumption is significantly lacking.

Immune boosting effects from extra vitamins and minerals:

As juice diets generally consist of fruit and vegetable juices, they may be dense in micronutrients including vitamins and minerals. However, the average person consuming a well-balanced diet, including fats, carbohydrates, proteins, and lots of fruits and vegetables, should already be meeting all of their nutrient requirements. While antioxidant vitamins found in fruit and vegetable juices may be seen as beneficial, it’s important to know that just because a nutrient has health benefits at a certain dose, it does not mean it has greater benefits beyond the recommended dose. Antioxidant compounds can in fact become pro-oxidants at high doses, causing detrimental health effects including the promotion of inflammation. Moreover, excess intake of fat-soluble vitamins A, D, E and K get stored in the body and can result in toxicity and serious health consequences.

Immediate nutrient absorption:

Fruit and vegetable juices may provide immediate absorption of some nutrients; however, this is not necessarily a good thing. Juices provide a large dose of sugar and lack fibre. Due to the absence of fibre in a juice, spikes in blood sugars and subsequent sugar crashes are common with juice diets. Whole fruits and vegetables, on the other hand, provide both nutrients and fibre. Fibre has a multitude of health benefits including bowel regularity, gut health, cardiovascular health, and blood sugar regulation. The lack of fibre in juices is especially important to consider for people with diabetes who may be at risk of more severe consequences from dramatic blood sugar fluctuations. Someone with diabetes should follow the diet recommended to them by their health care team. In general, people who consume whole fruits are at a lower risk of developing type 2 diabetes, whereas those who consume fruit juices are at a higher risk of developing the disease. Overall, immediate absorption of nutrients is not always beneficial and, in fact, it can often be detrimental to health.

Giving your GI tract a break and detoxifying your body:

The body is made to ingest and digest whole foods. It is specifically designed with all the mechanisms needed to break down whole foods and allow nutrients to be absorbed. The gastrointestinal tract does not need a break from whole foods as a nutritious and balanced diet does not cause damage to it. Generally, if someone has a damaged digestive tract, it is because they are suffering from an underlying health condition such as Celiac disease or Crohn’s disease where their intestinal lining is being damaged by specific triggering foods. In this case a therapeutic diet prescribed by a health care professional should be followed, rather than a juice cleanse. The body is also designed to rid itself of toxins. The digestive system, kidneys, liver, and lungs all contribute to toxin elimination. It’s important to consume a nutritious diet to allow your body to maintain optimal functions and therefore be able to clear toxins efficiently. A juice cleanse will not directly clear toxins or help your body do so.

Additional risks associated with detox diets and juice cleanses:

There are other risks associated with juice cleanses. For example, some juices may have high concentrations of a group of compounds called oxalates. These compounds can be found in foods such as beets, berries, cranberries, and dark green vegetables, which can contribute to the formation of kidney stones. Moreover, if a juice cleanse is paired with other cleansing strategies such as bowel stimulation (i.e. laxative use), there is a risk of dehydration and electrolyte imbalances resulting from excessive nutrient loss through the stool.

Final Recommendations for detox diets and juice cleanses::

Overall, I would not suggest anyone participate in a juice cleanse. Ideally, one should reach their nutrient requirements by consuming a well-balanced diet that includes healthy fats, proteins, carbohydrates and is high in fruits and vegetables. Juice cleanse diets are associated with a variety of negative health effects including dramatic blood sugar fluctuations, unsustainable weight loss, ineffective workouts, fatigue and many more.

Questions about your diet and nutrition needs? All University of Guelph students have access to Student Wellness Services nutrition services (free and fee-based options are available). Students can access these services in three ways: