Out of the following is not the physiological function of food:

Question

Accepted Answer

The correct option is 2:

"To provide mental peace" is the option that is **not** a direct physiological function of food; rather, it is classified as a psychological or emotional function. The science of nutrition defines food's physiological role by its direct impact on the physical, chemical, and anatomical workings of the body: providing energy, building and repairing tissues, and regulating life processes. Mental peace, which is a subjective state of mind, falls under the category of how food meets emotional needs, such as providing comfort, security, or a sense of well-being through familiar tastes or social contexts. While a balanced diet is necessary for optimal brain function, and certain nutrients can indirectly affect mood, "mental peace" is not a core, measurable biological mandate of the macronutrients and micronutrients that constitute food.

The incorrect option is 1:

"Provide energy to the body" is the most fundamental and primary physiological function of food. Our bodies are essentially machines that require continuous fuel to operate, and this fuel is supplied by the energy stored in food. This energy is primarily derived from the breakdown and metabolism of the macronutrients: carbohydrates and fats, and secondarily from protein. These nutrients are chemically converted into Adenosine Triphosphate (ATP), the molecule that powers all cellular activities, including breathing, blood circulation, muscle movement, and maintaining body temperature. Without this energy function, life processes would immediately cease, confirming it as a central physiological role.

The incorrect option is 3:

"Growth and development" represents the plastic or body-building physiological function of food, which is essential throughout the lifespan. This function is predominantly carried out by **Proteins**, which are broken down into amino acids. These amino acids are then reassembled to create new tissues for growth, such as muscle and bone mass in children and adolescents. In adults, this function continues as a constant process of maintenance and repair, where proteins and other structural nutrients replace old or damaged cells in organs, skin, and blood. Therefore, serving as the raw material for the physical structure and development of the body is a critical physiological contribution of food.

The incorrect option is 4:

"Protective and regulatory work" is the crucial third category of food's physiological functions, handled primarily by **Vitamins and Minerals** (micronutrients), as well as water and fiber. The regulatory function ensures the body maintains a stable internal environment, a concept known as homeostasis. This includes controlling body temperature, balancing water and electrolytes, and regulating the speed of metabolic reactions through enzymes and hormones. The protective function involves providing necessary components for the immune system, acting as antioxidants to defend against cellular damage, and facilitating critical processes like blood clotting. These processes are vital for long-term health and the prevention of disease.