When mice with human gut bacteria are given fructose plus a common food preservative called potassium sorbate, their intestines become more leaky than when they get fructose alone — meaning the preservative might make gut problems worse.

When mice with human gut bacteria were given a drink with 10% sugar (fructose) and a common food preservative (potassium sorbate) for 11 weeks, their livers got more fatty, inflamed, and scarred than expected—suggesting the two together are worse for the liver than either one alone.

When mice with human gut microbes were fed a mix of fructose and potassium sorbate, the fungi in their guts became less diverse, but the bacteria stayed the same—suggesting this food combo specifically hurts the fungal community.

Eating too much fructose, like the sugar in soda and candy, can damage the lining of your gut, letting harmful toxins leak into your bloodstream, which triggers body-wide inflammation and may lead to clogged arteries.