Low grade, controversial or vague ingredient we usually recommend avoiding
Lysine in dog food
L-Lysine is a necessary building block for all protein in the dog's body. It is an essential amino acid which means that it cannot be made by the dog and so must be eaten. Lysine is present in a wide range of foods, particularly meats, and so is present in all dog foods. Nevertheless, some dog food manufacturers top up the lysine levels with a nutritional supplement.