Molecular oxygen is the foundation of life on earth. The challenge is that the electrons in oxygen have a tendency to become unstable and reactive. When reactive oxygen comes into contact with biological systems, it triggers reactive oxygen species (ROS), also called free radicals. These damage cell components and lead to disease.

In order for life to evolve in a high oxygen environment, species had to develop antioxidants, which would help reduce the oxidation. Superoxide Dismutase (SOD) is the original enzyme with antioxidant powers that helped push evolution forward. Today science has discovered a connection between this important enzyme and multiple genetic and chronic illnesses.

Billions of years ago- Oxygen appears in the atmosphere leading to oxidation caused by free radicals. The ability to reduce oxidative stress was therefore required for life to exist. Free radical-fighting enzymes, like superoxide dismutase (SOD), are believed to have allowed for life as we know it to evolve.


The field of free radical biology was born with the discovery of SOD by two scientists named Joseph McCord and Irwin Fridovich.


The new understanding of the process of oxidative stress and antioxidants like SOD, trigger new scientific inquiry. Researchers began to study the impact of oxidative stress on toxicity and chronic disease.


SOD is established as the primary mechanism for scavenging superoxide radicals in the body and is named "SOD".


Dr. Daniele Toutai published a paper detailing her ability to isolate the SOD gene from a bacteria called Desulfoarculus baarsii. This led to the development of an understanding of the SOD genes found in certain types of single-cell organisms.


Exploration began with the SOD gene. Animal studies found a connection between SOD dysfunction, illness, and infertility.


More is learned about the role of SOD in the cells and its ability to protect against oxidative stress. Researchers begin to understand the fine balance of SOD that single-cell organisms require to reduce oxidative stress without toxicity.


A paper is published in the Journal of Biological chemistry reporting the details of the activity of SOD.


Research begins to focus on the impact of SOD on disease. People with the familial form of amyotrophic lateral sclerosis (ALS) have mutations in one of the SOD genes.


A comprehensive list of how SOD-type enzymes work was published in the Journal of Inorganic Chemistry which helped guide future directions for research.


The connection between an imbalance of SOD and trisomy 21 or Down syndrome is elucidated. People with this genetic condition have an over-expression of pro-oxidant genes and mitochondrial dysfunction, linked to a dysregulation of how the body uses SOD.


Research finds SOD may be linked to the development of cancer and some cardiovascular diseases.

2015 and beyond

Interest in the science of free radicals and SOD continues. SOD is found to be linked to heart disease, inflammatory conditions, neurodegenerative disease, and aging.

This page is for educational purposes only and is not intended to diagnose, treat, cure or prevent any disease. Individuals with health concerns or on medication should check with their health care practitioner before trying any new type of eating plan.