What is a nutrient?

A nutrient is a substance that an organism needs to live or grow. This definition underscores the vital role nutrients play in biological processes, as they contribute to growth, reproduction, and overall health. Nutrients can be categorized into macronutrients and micronutrients, including carbohydrates, proteins, fats, vitamins, and minerals, which are consumed in various forms through diet. These substances are essential for energy production, immune function, and cellular repair.

In contrast to the incorrect options, a chemical that damages body cells does not describe a nutrient but rather a toxin or harmful substance. An element that has no effect on health does not fulfill any biological purpose, so it cannot be classified as a nutrient. Likewise, a type of waste product refers to substances that the body eliminates, rather than those it requires for essential functions. Overall, the concept of nutrients is fundamental to understanding health, nutrition, and biology as they are crucial for sustaining life and promoting growth.