5-ALA is close in form to other amino acids such as gamma-aminobutyric acid (GABA) and ornithine, but its origin go back far longer. 

It can be traced back to a common ancestor of all organisms on the Earth today that existed 3.6 to 4 billion years ago.

There is only one role for 5-ALA in the human body, and that is as a component of a substance called heme (haem). 

Heme, formed by a combination of eight 5-ALAs, is the key to a number of vital activities.
A familiar example of heme activity is the formation of red pigment (hemoglobin) in the blood, which distributes oxygen throughout the body. 

Oxygen and heme combine and separate depending on the surrounding environment, and oxygen is delivered from the lungs throughout the entire body.

In addition, heme is the central substance in the respiratory chain complex that produces energy from food and oxygen, which is the basis of our vital activities. 

Without 5-ALA we would not be able to gain energy or even move.
Chlorophyll, which plays a central role in plant photosynthesis, is also formed by combining eight 5-ALAs, and its structure is very close to heme.

Plants produce oxygen and cells by photosynthesis using light and carbon dioxide. 

Animals, including humans, consume oxygen and plants and exhale carbon dioxide, and plants grow again using that carbon dioxide. 

This is the energy cycle of life, which has been in operation since ancient times, and it cannot be achieved without its two axes—heme and chlorophyl— both of which are formed from 5-ALA.