Freeze-dried bacteria from the guts of healthy people could be the key to tackling asthma, Alzheimer's, Parkinson’s disease and even cancer, experts believe.

British scientists have isolated several strains of friendly bugs which appear to have significant effects on the immune system, and hope they could replace harsh chemotherapy drugs or steroids.

The first trials have now begun to see if introducing just a single species of bacteria in pill form could benefit a huge range of diseases.

The human gut contains trillions of bacteria - known collectively as the microbiome, which has evolved with us over millions of years. But the overuse of antibiotics and hyper-cleanliness in everyday life can kill off helpful bugs, contributing to the rise of disease.

A recent study by University College London (UCL) found that a single course of antibiotics can alter the microbiome for at least a year, and poor gut health is now linked to the development of Alzheimer’s, Parkinson’s, Crohn’s disease, asthma, allergies, inflammatory bowel disorder (IBS), diabetes, multiple sclerosis, autism, cancer, and even HIV.

Duncan Peyton, founder and CEO of British company 4D pharma, which is launching the first trials into a new era of biotherapeutics, believes that replacing the missing bacteria could restore good health.