Twenty years ago, seeing the letters "GF" on a menu could have been easily mistaken for “good food.” But today, it is the near-universally recognized shorthand for gluten-free. That’s in part a testament to the rapid rise in the number of people with the chronic autoimmune condition known as celiac disease, which affects as many as 2 million Americans — most of whom are women.
The reason why celiac disease has become so common is not entirely known, but it speaks to a bigger trend where autoimmune diseases are on the rise. Autoimmune diseases occur when the immune system mistakenly attacks healthy cells in a person's body. Other examples are multiple sclerosis, type 1 diabetes, asthma, eczema, lupus and rheumatoid arthritis.
