This is the Guardian. Hi Ian Sample here. If you heard Tuesday's episode you'll know that the Science Weekly team are off on their summer break

So for a couple of weeks we're running some of our favorite episodes from the year so far

Today it's one of mine on how Western lifestyles

might be contributing to rising rates of autoimmune disease delving into the

fascinating interactions between genetics, the environment and our immune systems.

I hope you enjoy it. Auto-immune diseases are on the rise around the world.

Auto-immune diseases are on the rise around the world.

According to the National Institutes of Health, one in 15 Americans suffer from an autoimmune disease.

In the Pacific Northwest, there is a greater prevalence of MS, irritable bowel disease, and

type 1 diabetes, all autoimmune related.

Many you will have heard of, like rheumatoid arthritis, type 1 diabetes, an inflammatory bowel disease.

In the UK, autoimmune diseases now affect more than 1 in 10 adults.

A busy personal trainer started to lose hair, gain weight, and her get up and go, got up and went.

She suspected something was wrong

Talia says medical test revealed she suffered from Hashimoto's an autoimmune

disease that attacks her thyroid and curiously some have begun to turn up in countries that have never reported cases before.

So what's behind the rising cases and could our modern lifestyle potentially be to blame?

From the Guardian I'm E insemble and this is Science Weekly.

To understand why autoimmune diseases are becoming more common around the world, I spoke to James Lee, a clinical science group leader at the Francis Crick Institute and a consultant

gastrointestinalologist at the Royal Free Hospital in London.

James, could you explain for us what an autoimmune disease actually is?

An autoimmune disease is a chronic usually lifelong condition and the way I like to try and to explain it to my patients when I'm seeing them in clinic is that essentially your immune system has got its wires crossed.

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