The primary roles of the major nutrient types in human health include providing energy, supporting growth, and regulating bodily functions. Carbohydrates serve as the main energy source, while proteins are essential for muscle repair and growth. Fats play a crucial role in hormone production and cellular integrity. Vitamins and minerals are vital for metabolic processes and maintaining immune function. Consuming a balanced diet rich in these macronutrients and micronutrients ensures that the body operates optimally and supports overall health.