Juice cleanses can be harmful

Contrary to popular belief, juice cleanses may do more harm than good―even in as little as three days.

 

A US study published in Nutrients found that a vegetable and fruit juice-only diet can disrupt the gut and oral microbiome, triggering an increase in bacteria linked to inflammation and cognitive decline. “Most people think of juicing as a healthy cleanse, but this study offers a reality check,” cautioned the author.

 

To examine the health impact of juicing, researchers studied three groups of healthy adults, aged 18 to 35. For three days, one group consumed only fruit and vegetable juice, another had juice along with whole foods, and a third group ate only whole plant-based foods.

 

The researchers collected saliva, cheek swabs and stool samples before, during and after the diets to analyse bacterial changes. The juice-only group experienced the most significant increase in bacteria associated with inflammation and gut permeability, often referred to as "leaky gut." The juice-plus-food group showed some bacterial changes, but not to the same extent. In contrast, the plant-based whole food group showed more favourable microbial changes. The juice-only diet also caused significant changes in the oral microbiome, reducing beneficial bacteria and increasing bacteria linked to inflammation.

 

The researchers attribute these changes to the high sugar and low fibre content of juices. Reduced fibre intake can adversely impact metabolism, immunity and even mental health.

 

The lead author warns, “Consuming large amounts of juice with little fibre may lead to microbiome imbalances that could have negative consequences, such as inflammation and reduced gut health."

Health