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A few days of a juice only diet is viewed by many as healthy, and a good way to cleanse the body. But... a recent study found that this is not true for the gut microbiome (the community of fungi, bacteria, and viruses), which is so important to our health. A vegetable and fruit juice only diet, even if it's only for three days, is unhealthier than juice plus whole foods, or only whole-plant foods diet.
The juice only diet promoted the growth of bacterial species in the gut that are linked to gut permeability, inflammation, and cognitive decline. The juice only diet also resulted in changes in the saliva and cheek microbiota (microbiome), especially an increase in pro-inflammatory bacteria. The researchers thought these changes were due to the low fiber intake of the juice only diet.
This is because fiber feeds the beneficial bacteria (linked to good health) in the gut. Juices are low in fiber, but whole fruits and vegetables are high in fiber (as are whole grains, seeds, nuts, legumes).
Participants in the study were divide into 3 groups. Each group followed one diet (juice only, juice + food, or whole plant based foods only) for three days. Bacteria in the mouth (saliva and cheek swabs) and gut (through stool samples) were analyzed before, during, and after.
Before participants followed one of the 3 diets, they first followed an elimination diet for 3 days: organic fresh fruits, vegetables, gluten-free whole grains, eggs, and 8 glasses of water a day. No alcohol, caffeine, sugar, processed foods, dairy, red meat, and gluten (e.g., wheat, rye, barley, spelt). This diet also had beneficial changes in the gut microbiome with increased numbers of bacteria linked to good health, for example, an increase in the gut bacteria Faecalibacterium prausnitzii.
From Medical Xpress: Juicing may harm your health in just 3 days, study finds
Think your juice cleanse is making you healthier? A new Northwestern University study suggests it might be doing the opposite. The study, recently published in Nutrients, found that a vegetable and fruit juice-only diet—even for just three days—can trigger shifts in gut and oral bacteria linked to inflammation and cognitive decline. ...continue reading "A Juice Only Diet Is Not Good For the Gut Microbiome"