Which substance is included in the non-nutrient class?

Fiber is classified as a non-nutrient substance despite being a crucial component of a healthy diet. While it plays significant roles in digestion, including promoting regular bowel movements and contributing to feelings of fullness, fiber is not considered a nutrient in the traditional sense. Nutrients typically refer to substances that provide essential energy or building blocks for the body, such as carbohydrates, proteins, fats, vitamins, and minerals.

Fat, protein, and minerals, on the other hand, are classified as macronutrients or micronutrients that the body requires in varying amounts for growth, energy production, and overall metabolic functions. These substances have specific roles, such as providing energy (fats and proteins) and facilitating numerous biochemical processes (minerals).

In contrast, while fiber is beneficial and essential for health, it does not provide energy (calories) and is not absorbed in the same manner as other nutrients. This distinguishes it in the context of nutrition, affirming that fiber falls into the group of substances that, while important, are not classified as essential nutrients.