Free Radicals and Aging

Our bodies contain numerous antioxidant enzymes that defend against free radicals. Free radicals are chemicals with extra or unstable electrons, and these unstable electrons can wreak much havoc if they leave the free radicals for surrounding cells of the body. A free radical is kind of like an evil santa clause that gives away presents that contain time bombs. Antioxidants are like the bomb squad. Over time, it is inevitable that free radicals progressively damage many tissues and cells in the human body, and this is thought to be a possible cornerstone of aging. Free radicals are a necessary part of biological metabolism. Our mitchondria employ them in the process of turning our food into energy, and free radicals inevitably "leak" out to damage tissues. While our natural antioxidant enzymes and other proteins, such as glutathione, superoxide dismutase, and catalase, are capable of preventing many of these evil santa clauses from doing a lot of damage, they are incapable of preventing the damage all the time. In the same fashion that christmas day is inevitable, when explosives hang under the mistletoe, also inevitable is the use of free radicals in mitochondria when food molecules are converted into storable energy. Thus, in order to reduce oxidative damage that free radicals wreak, getting antioxidants to neutralize those that roam outside their metabolic zones has been a major focus of research.

It is thought that compounds that either boost the activity of natural internal antioxidants, or that act as good antioxidants themselves, could perhaps lessen the damage our bodies continually incur from free radicals. Depending on the specific involvement of free radical species involved in aging and how well these antioxidants do their job, it is thought that antioxidants can significantly extent lifespan.

It is important to keep in mind that not all antioxidants are created equal. Within the natural antioxidants produced in our bodies, they all have completely different ways of going about deactivating free radicals. Additionally, some specifically target only one type of free radical out of many. It's kind of like some members of the bomb squad are capable of diffusing your average C4 bomb, while others can only diffuse nuclear bombs.

It is thought that the Eukarion compounds discussed below are better at scavenging free radicals than our native enzymes, and this is thought to be the reason why they extend lifespan. The daf-2 family of genes discussed below are thought to boost our native antioxidant systems, and the increased free radical capturing is thought to be at least partially responsible for the daf-2 mutation increasing longevity.

by Chris Smelick at