Billy Bob Thornton explains reasoning for 'very restricted' diet Billy Bob Thornton has a "very restricted" list of foods he can eat due to various health issues. 10 May 2026 Billy Bob Thornton's diet is "very restricted" due to rare health issues. Billy Bob Thornton has a restricted diet The Landman actor has a number of food allergies and believes his rare blood group has led to additional stomach issues, despite no studies definitively showing a clear link between blood type and help. Speaking on the Howie Mandel Does Stuff podcast, Billy Bob explained: "Well, I'm allergic to wheat, dairy.