Lamb is a rich source of protein. Protein is an essential macronutrient that is required for growth, repair and maintenance of tissues in the body. Lamb contains all the essential amino acids required by the body, making it a complete protein source. Additionally, lamb is also a good source of other nutrients such as vitamin B12, zinc, and iron. These nutrients are important for maintaining a healthy immune system and supporting various metabolic processes in the body. However, lamb is not a significant source of carbohydrates or vitamins.