lisbeth hasselbeck like millions more has celiac disease, a genetic disorder that makes a person intolerant to gluten. dana vollmer, like more and more peel, feels better when she stops eating foods containing gluten. what is gluten? a protein found in wheat, rye, barley, and other grains, and many processed foods. soups, salad dressings, sauces, too. >> i think everybody should be off gluten. >> reporter: this doctor is a practitioner of a functional approach to healing, and a prophet of going gluten-free. >> most people, when they stop gluten, lose weight, are energized, aches and pains free up. they have more energy and they sleep better. it affects every system in the body. >> reporter: buffett doctor's biggest fans, tabatha coffey. >> i'm done. >> reporter: star of "tabatha takes over" on bravo. >> i am tabitha and i hate it when things give me a hard time. glueden was giving me a really hard time so i had to tell it to [ bleep ] off. >> reporter: lisbeth hasselbeck had to agree, a bit more demurly. >> i feel like my name should be in here. i hang out here. >> reporter: we talked to he