What is the role of nutrients: 1. Nutrients provide materials for growth and repair. 2. Nutrients provide energy to keep your cells alive. 3. Nutrients provide vital elements and compounds to maintain the chemical reactions in your cells. Nutrients A nutrient is a substance needed by organisms to stay alive and healthy. A healthy human diet involves seven different kinds of nutrient: nutrient: carbohydrates proteins lipids(fats and oils) minerals vitamins dietary fibre water Some foods are particularly rich in certain nutrients. The table shows why we need each nutrient, and some good sources of each one: