Catabolism: What is it? Activity, Relationship with Anabolism, Cells and ATP Molecule

It is a series of chemical reactions (through metabolic pathways in the body) that break down complex molecules into smaller units and release energy.

This released energy is stored inside the molecule of adenosine triphosphate (ATP). The metabolism is divided into two processes: Anabolism and catabolism.

Catabolism, destructive metabolism, produces the energy necessary for physical activity from a cellular level to any movement of your body.

Catabolism is the process involved when your body breaks down larger molecules into smaller molecules, and it is one of two chemical processes and reactions that form your metabolism.

The other half of the equation that makes up your metabolism is called anabolism—catabolism releases energy during the decomposition process of organic nutrients stored within the adenosine triphosphate molecules.

Energy is stored as chemical bonds with high energy, and these bonds are found between the second and third phosphate molecules.

This energy is the fuel for the anabolic reactions used by the cells, so the hormones, enzymes, sugars, and other molecules needed by the cell can be synthesized. The cell can grow, reproduce and maintain itself.


The ATP that stores energy is used to synthesize more complex cell components from small, simple building blocks.

To transport substances through the cell membrane and for the movement and contraction of cells.

Adenosine triphosphate releases energy when the chemical bond is broken, and this results in the molecule becoming adenosine diphosphate, or ADP after the stored energy is released.

Catabolism can co-occur as anabolism in the cell, but these two metabolic processes operate independently and use different pathways.

Catabolism is also known as destructive metabolism, and this process never ends. This part of the metabolism produces the energy necessary for physical activity from a cellular level to any movement of your body.

Catabolism activity

It also releases the energy necessary for your body to maintain the correct temperature and helps break down complex molecules and chemicals into simple units.

These units are waste products and can be excreted from the body through their organs, including the intestines, kidneys, skin, and lungs.

It is part of the process that determines whether you gain or lose weight or maintain your weight. If more energy is released from the cells than it is absorbed, this will cause a loss of weight.

If you consume more energy, in other words, calories than what is released through catabolic action, you will gain weight gain.

The cells use ATP to:

  • Synthesize cellular components.
  • Contraction and movement of the muscle of power.
  • Substances of transport through cell membranes.

Catabolism is the opposite of anabolism, which is the process of creating more significant and more complex molecules through metabolic pathways.

Examples and types of catabolism

The types of large molecules typically decomposed by catabolism include:

  • Polysaccharides (starches and glycogen).
  • Lipids (fats)
  • Nucleic acids.
  • Proteins

These large molecules are broken down into smaller units like:

  • Monosaccharides (simple sugars such as glucose, fructose, and galactose).
  • Fatty acids.
  • Nucleotides (which are chemical energy sources for ATP and guanosine triphosphate) and cofactors of enzymatic reactions).
  • Amino acids.

How catabolism and anabolism are related to metabolism

Catabolism and anabolism are the two fundamental metabolic processes in the body that maintain life. Catabolism breaks down organic material to “produce” energy.

Anabolism uses that energy to build critical cellular components such as nucleic acids and proteins; therefore, catabolism is often considered “something bad.”

It is a prerequisite to produce the chemical energy that the body needs to create new cellular material and tissue, as well as to repair, grow and maintain existing tissue.

When the rate of catabolism exceeds the rate of anabolism (for example, when a person is in a calorie deficit), net tissue is lost.

When anabolism is more significant than catabolism (i.e., a state of excess energy), a net gain of tissue is obtained. When catabolism and anabolism are in a state of relative equilibrium, the results of balance and net tissue levels remain constant.

What controls catabolism?

Catabolism is controlled through signals sent from hormones in the body.

These hormones usually include cortisol (which the body produces under physical or mental stress), glucagon, adrenaline, cytokines, orexin, and hypocretin.