What is Metabolism?

Metabolism is the sum of all chemical reactions that occur inside living cells to maintain life. It includes processes that break down nutrients to produce energy (catabolism) and processes that build complex molecules needed for growth and repair (anabolism). Every living organism, from bacteria to humans, depends on metabolism to survive.

Catabolic reactions, such as digestion and respiration, release energy by breaking large molecules like carbohydrates and fats into smaller ones. Anabolic reactions, like protein or DNA synthesis, use that energy to build essential components of the body. Together, they keep the organism functioning smoothly.
The energy released is stored in molecules like ATP (adenosine triphosphate), often called the energy currency of cells. Factors like age, diet, hormones, and physical activity influence metabolic rate.

A fast metabolism burns energy quickly, while a slow one conserves it. Maintaining balanced metabolism is vital for health—it controls body temperature, repair mechanisms, and overall energy use. In essence, metabolism converts food into fuel and materials your body needs to grow, heal, and perform daily tasks efficiently.