I was very surprised to see that Lean Treats contain High Fructose Corn Syrup and corn, neither of which is recommended for diabetic dogs! According to Entirely Pets, which lists the ingredients, they are:
Chicken Liver, Skinless Chicken,Corn, Chicken By-Product Meal, High Fructose Corn Syrup, Wheat Flour, Glycerin, Phosphoric Acid, Salt, Potassium Sorbate and Calcium Propionate, and BHA, Citric Acid (Preservatives), Propylene Glycol, Iron Oxide.
Corn is the 3rd biggest ingredient and HFCS the 5th. They also contain wheat flour. I try to give my diabetic dog grain free treats, and I don't think these would be good. The recent newsletter from Dr. Sutton recommended them for diabetic dogs!