The number of people suffering from one or more autoimmune diseases has been rising steadily over the last 40 years. According to the Autoimmune Association, more than 24 million Americans are affected by an autoimmune disease and 80% of these are women. And now researchers say that one of the main causes of this growth could be the pervasiveness of fast food.

According to the New York Post, scientists James Lee and Carola Vinuesa at London’s Francis Crick Institute say that the typical Western diet lacks critical nutrients which can lead to autoimmune disorders.

“Numbers of autoimmune cases began to increase about 40 years ago in the West,” Lee said. “However, we are now seeing some emerge in countries that never had such diseases before.”

The immune system normally can distinguish invading pathogens from its own cells. However, immune cells can make a mistake and attack healthy tissues instead. This can lead to a variety of autoimmune diseases that can affect an organ, such a Hashimoto’s thyroiditis that involves the thyroid, or the whole body such as rheumatoid arthritis or systemic lupus erythematosus.

Type 1 diabetes, multiple sclerosis, vitiligo (loss of pigment in the skin), and myasthenia gravis, which affects muscle receptors, are other examples of organ specific autoimmune diseases.

Lee said that the number of cases of inflammatory bowel disease in Asia and the Middle East has been on an upswing coinciding with the boom of the fast food industry in these areas. “Before that they had hardly seen the disease,”

In the U.S., studies by the National Institutes of Health have shown an increase in autoimmune disorder biomarkers for those ages 12 and up from 22 million Americans between 1988 to 1991, to 41 million between 2011 and 2012, says the Post.

“Human genetics hasn’t altered over the past few decades,” said Lee. “So, something must be changing in the outside world in a way that is increasing our predisposition to autoimmune disease.”

Vinuesa supports the theory that our changing diet may be responsible for the epidemic of autoimmune disease.

“Fast food diets lack certain important ingredients, such as fiber, and evidence suggests this alteration affects a person’s microbiome — the collection of micro-organisms that we have in our gut and which play a key role in controlling various body functions,” she told the Guardian's Observer. “These changes in our microbiomes are then triggering autoimmune disease, of which more than 10 types have now been identified.

Gluten sensitivity is a common example of an autoimmune disorder that seems to be more prevalent today. Dr. Robert G. Lahita, director of the Institute for Autoimmune and Rheumatic Disease at St. Joseph’s Health, New Jersey, and the author of Immunity Strong, says that gluten becomes the antigen or trigger for the immune system.

“Autoimmunity happens in our body as a normal process,” Lahita tells Newsmax. “It is not a harmful thing until disease develops. But it is possible that autoimmunity is a major aspect of inflammation and consequently at the heart of most of our most common diseases like those affecting the heart, lungs and brain.”

The British researchers point out that not everyone who eats fast food will develop these autoimmune disorders.

“If you don’t have a certain genetic susceptibility, you won’t necessarily get an autoimmune disease no matter how many Big Macs you eat,” Vinuesa said, according to the Post.

Scientists hope to identify the genetic variants that may cause autoimmune disorders so that targeted therapies can be developed. Currently there are no cures for these diseases but hopefully with DNA intervention, they can be managed.

“Growing numbers of people face surgery or will have to have regular injections for the rest of their lives,” said Lee. It can be grim for patients and a massive strain on health services. Hence the urgent need to find new, effective treatments.”