As for why it matters: having elevated levels of inflammation-causing bacteria long-term can cause health problems like heart disease, autoimmune conditions, and mood challenges, says Dr. Rajapaksa. “Our gut microbiome is linked to almost every health condition,” she says. Basically, it’s not something you’d want to neglect.

Juice cleanses promise detox and vitality but may disrupt gut health by eliminating fiber, the microbiome's essential fuel.

Many people go on juice fasts in the belief that doing so would rid their bodies of toxins. But juicing may be affecting gut health in unexpected ways.