What Exactly is a "Free Radical" and What They Do to Your Skin

Many of the subjects regarding you skincare are scientific and medical based and at their best are difficult to understand. Dr Gary Weinberger, our Executive Director will attempt here to explain one of those issues – free radicals.


These free radicals have many of the characteristics exhibited by substances known to cause cancer and possibly contributing to the initiation of the processes resulting in cancer. For example, ROS/NOS can cause alteration of DNA. DNA is the building block of our genetic material and simply put the ROS and NOS free radicals can cause genetic damage by causing base pair (genetic) mutations, gene deletions and rearrangements, insertions and sequence amplifications. ROS can cause gross alterations to the genes at specific locations on certain chromosomes. This type of alteration may result in the inactivation of a “suppressor” gene, those genes that block the formation of certain cancer cells, allowing for expression of the tumor phenotype. Lastly, ROS/NOS can change the activity of proteins and genes that respond to environmental stress which then alter the genes that are related to cell proliferation and to normal cell death (apoptosis). No longer under the influence of these control genes, cells would no longer die a normal death but instead live longer and multiply abnormally (cancer cells). This understanding of free radicals, hopefully, will help the consumer to better understand the beneficial role of antioxidants like, lycopene , in protecting their skin from the harmful effects of environmental free radicals like pollutants in the air and the sun’s UV rays.

It is well known that “free radicals” may play a key role in the development of human cancer. The role of antioxidants in preventing or delaying the onset of some of these cancers is growing within the scientific community. There are two major groups of free radicals that have been implicated as playing a key role. The first is a group is composed of the reactive oxygen species or ROS and the second group is the lesser known but no less important reactive nitrogen species or NOS. The term ROS is a term used by biologists and includes oxygen radicals [superoxide (O2-), hydroxyl (OH-), peroxyl (RO2), alkoxyl (RO)] as well as certain non-radicals that are either oxidizing agents and/or easily converted into radicals, such as HOCL, ozone (O3), peroxynitrite (ONOO-), singlet oxygen (O2), and H2O2. Basically, these are oxygen containing molecules that are highly reactive with other compounds. The easiest way to imagine this chemical reaction is to think of the formation of rust. Oxygen in the air combines with iron molecules (Fe+) in the metal to form rust or iron oxide. This kind of reaction also happens in biological systems with the resulting oxidized molecules causing damage to the body’s cells and organ systems. Similarly, RNS is a term coined by biologists that includes nitric oxide radical (NO), ONOO-, nitrogen dioxide radical (NO2), other oxides of nitrogen and products that result when NO reacts with O2-, RO, and RO2. These molecules will combine in a fashion similar to oxygen creating new compounds that also have the ability to do cellular damage. Many of these ROS and NOS compounds are found in the environment as a result of pollution.