The Contribution of Antioxidants and Phytochemicals

Early bacteria living in Earth’s oxygen-poor atmosphere learned to extract energy from the sun — by combining the energy with carbon dioxide from the air and water from the ocean, they were able to form the glucose they needed for their cells to function. This process, known as photosynthesis, gave these bacteria a huge advantage over competing species, but created a problem: the oxygen they produced as a byproduct of this chemical reaction threatened to destroy them through oxidation of their DNA. So, they developed specialized antioxidants called phytochemicals, which have properties that enable them to absorb the extra electrons found on oxidized chemicals and oxygen radicals. Phytochemicals are truly sponges for oxygen radicals.

In the human body, different types of antioxidants are found in specific locations where they can be most effective. For example, some act only in the oily environment of fat cells while others act in the liquid, water-like environment of muscle cells. This latter adaptation is particularly important, as the primary energy producers within muscle cells, the mitochondria, also leak oxygen radicals in oxygen-poor environments. The ability of antioxidants to mop up these radicals enables them to play an important role in the fight against cell damage and the development of cancer. This is where exercise can be particularly useful — exercise increases the levels of many antioxidants in the muscles, thus reducing the levels of dangerous free radicals.