Scientists from the Francis Crick Institute in London say that more people are suffering because their immune systems are unable to differentiate between healthy cells and outside micro-organisms that have invaded the body.
James Lee and Carola Vinuesa, both group leaders at the biomedical research institute, are leading two separate research groups that are aiming to help identify what the exact causes of autoimmune disease are.
Autoimmune diseases occur when the body’s natural defence system becomes confused and mistakenly attacks normal cells. There are more than 80 types of autoimmune disease, ranging from rheumatoid arthritis to inflammatory bowel disease (IBD), type one diabetes and multiple sclerosis.
These lifelong conditions are incurable and often develop in young people. They affect approximately four million people in the UK.
Previous studies have suggested that the prevalence of autoimmune disease has been rising over the past 40 years, with a 2018 report showing some illnesses increased by nine per cent each year.
He added: “Human genetics hasn’t altered over the past few decades. So something must be changing in the outside world in a way that is increasing our predisposition to autoimmune disease.”
Vinuesa, who backed Lee’s hypothesis, pointed towards Western diets becoming more widespread across the world and more people buying fast food.
She said that the lower nutritional value of fast food could affect a person’s microbiome, which refers to micro-organisms that exist in the gut and play an important role in ensuring bodily functions operate as they should.
But diets that are heavy in fast foods could be leading to changes in the microbiome, which could be responsible for “triggering autoimmune disease”, Vinuesa said, adding that there is “not a lot we can do to halt the global spread of fast food franchises”.
But some people carry “certain genetic susceptibilities” that could make them more vulnerable to autoimmune disease. The scientists are setting out to try and understand the “fundamental genetic mechanisms that underpin” these conditions in order to tackle the issue.
They are doing this by using new techniques to identify small DNA differences among large groups of people, which in turn will help identify common genetic patterns among autoimmune disease sufferers.
The researchers hope this will help develop targeted treatment, particularly for diseases that have different versions caused by different genetic pathways.