White bread boosts good gut bacteria

White bread seems to have gained a bad reputation in recent years - but scientists say this reputation may not be totally deserved.

A study in the American Chemical Society’s Journal of Agricultural and Food Chemistry reports that white bread appears to encourage the growth of beneficial gut bacteria.

They also note that when looking at the effect of food on the human microbiome, it’s critical to consider the whole diet, not just individual ingredients.

Author Sonia González and her colleagues investigated the role of polyphenols on gut bacteria - specifically, how polyphenols and fibres together help balance gut microbes.

The surveyed 38 healthy adults about their diets and assessed the bacteria present in participants’ stool samples. They found that, surprisingly, white bread boost Lactobacillus, a group of beneficial bacteria.

Their analysis also showed that pectin, a compound in citrus fruits, lowers the level of some helpful bacteria. This finding directly contradicts previous research that has analysed pectin in isolation. González and colleagues suggest that pectin interacts with other substances in oranges, leading to this unexpected effect.