Physiological Aspects of Food:
The physiological functions of food include energy- giving, body- building, protective and regulatory functions.
Energy-giving:
What is energy?
It is the power derived from the utilization of chemical resources derived from food intake. It is the strength and vitality required to sustain physical and mental activity. In simple words energy is the capacity to do work. We need energy to perform functions such as growth, maintaining balance, repair, reproduction, movement and defense etc.
How do we acquire energy?
Energy comes from the food we eat. Our bodies digest the food we eat by mixing it with various fluids such as acids and enzymes and break down the complex food substances into simple substance.
We require energy for every action we do voluntarily and involuntarily. Voluntary actions include using your hands for writing, legs for walking and running, exercising, talking etc and involuntary actions that we are both aware and unaware of include blinking of eyes every 6 sec, pumping of the heart, gastro intestinal peristaltic movements etc. the energy giving function is performed majorly by two nutrients carbohydrates and fats. These nutrients are referred to as “body-fuels”.
Body- building, growth repair– Our body is made up of millions of cells. When growth takes place new cells are added to the existing ones and the existing ones also increase in size. Cells also get worn out and die and these cells have to be replaced. This process is called repair. For both growth and repair proteins are necessary. The growth curve should substantially increase from new born to adult life which is not possible without proper protein intake.
In other words the fuel to growth of our body and mind is achieved by taking the right food in right quantity. Not only the quantity of food is important but also the quality that determines the size, shape and contours of our body in addition to genetic influence.
Protective and regulatory function- Protective refers to the role in preventing infections by ensuring proper functioning of the body systems responsible for fighting infections. Regulatory function refers to the role of food controlling body processes such as beating of heart, contraction of muscles etc. This is achieved by specific nutrients namely vitamins, minerals and proteins. So does water.
Water is also an essential nutrient to maintain fluid and electrolyte balance. It is the major component of all cells and tissues of the body. It accounts for 60-70 percent of the total body weight. It plays a key role in elimination of body wastes and regulation of body temperature.
Thus foods contain a wide variety of nutrients that our body converts into energy for physical and mental activities. It provides nutrients to the body required for activity and growth. People who eat healthy and balanced diet are likely to have plenty of energy to work, fewer infections and other illnesses.