Two years ago, I lay paralysed in a hospital bed, unable to use my arms or legs, to hug my young son or daughter, or to type a word to meet an impending book deadline. Autoimmune diseases, a group of about 100 conditions in which the body's immune system turns on the body itself, are reaching epidemic proportions. In the past decade, 15 top medical journals have reported rising rates of lupus, multiple sclerosis, scleroderma, Crohn's disease, Addison's disease and polymyositis in industrialized countries worldwide. Over the past 40 years, rates of Type 1 diabetes have increased fivefold; in children 4 and under, it's increasing 6 percent a year. My paralysis was caused by Guillain-Barre syndrome, in which body's immune system destroys the nerves' myelin sheaths, short-circuiting messages from the brain to the muscles. I've been paralysed twice in the past seven years. Months of rigorous physical therapy and treatment have enabled me to walk again. But remnants of the disease