Billy Bob Thornton, the Landman actor, has revealed that he has a rare health condition that restricts his diet. Thornton, who is allergic to wheat, dairy, and meat, has type AB-negative blood, which is the rarest type in the world and is less than 1% of the population of the world. This type of blood type causes stomach issues and leads to less digestive enzymes. Despite this, Thornton maintains his strict diet and has stated that he is not a vegan who cheats but doesn't cheat so bad. He first learned of his rare blood type in late '80s and has since eliminated wheat, Dairy, red meat, and more from his diet, according to Mashed.