The term NOURISHING SUBSTANCE can be broken down into two crossword solutions: NUTRIENT (8 letters) and FOOD (4 letters). Nutrients are substances found in FOOD that are essential for the body to function properly. They provide energy, build and repair tissue, and regulate bodily processes. FOOD is any substance consumed to provide nutritional support for an organism. It is usually of plant or animal origin and contains essential nutrients, such as carbohydrates, fats, proteins, vitamins, or minerals.