Food preservatives are an everyday norm for many consumers, and feature in a huge array of products in order to extend their shelf lives and prevent spoilage.
Where food preservation was once crucial to human survival, it has now become a massive global industry that is fuelled by growing demand for convenience foods and products that last longer.
But recent research has shown that some types of food preservatives could affect our health and wellbeing, including our gut health.
Whether food preservatives are definitively bad for our gut health has not been shown, but a recent study suggests that one common preservative could interfere with a healthy gut microbiome.
Nisin, a type of lantibiotic that has been widely used in the food industry over the last few decades. It is often found in processed cheese, as well as meats, alcohol and tinned food, like tinned potatoes, peas, and soups.
It was first discovered in England in 1928, but began being used as a food preservative in the Fifties.
A study conducted by researchers at the University of Chicago and the University of Illinois at Urbana-Champaign found that nisin can have a potent effect on both pathogens – which helps stop food from spoiling – but also on gut bacteria that promotes health and wellbeing.
Zhenrun Zhang, PhD, one of the study’s authors, said: “Nisin is, in essence, an antibiotic that has been added to our food for a long time, but how it might impact our gut microbes is not well studied.
“Even though it might be very effective in preventing food contamination, it might also have a greater impact on our human gut microbes.”
The researchers analysed the effect of lantibiotics like nisin on pathogens and commensal gut bacteria. Commensal gut bacteria help the body break down nutrients, produce metabolites and protect against pathogens.
But if too many commensal bacteria are killed off by food preservatives, it is suggested that more aggressive pathogens could take the opportunity to wreak havoc on the gut.
Even though different lantibiotics had different effects, the researchers found that they killed both pathogens and commensal bacteria indiscriminately.
“This study is one of the first to show that gut commensals are susceptible to lantibiotics, and are sometimes more sensitive than pathogens,” Zhang said.
“With the levels of lantibiotics currently present in food, it’s very probable that they might impact our gut health as well.”
