For Akkermansia he said pomegranates, dried cranberries, concord grapes, either whole or juiced, chilis, black raspberries and Chinese black vinegar were good options.

‘These are achievable ways to actually cultivate this one bacteria,’ he said.

For the other three bacteria, Dr Li recommended people store cooked carbohydrates, like rice, potatoes pasta, overnight in the fridge to turn them into the resistant starch the microorganisms needed to thrive.

He explained this cooling process causes a reaction in the food which makes slower to digest to the better of positive bacteria growth in your digestive system.