It Surprised Me to Learn That Our Bodies Have Hydrogen Peroxide in Them

Hydrogen peroxide is produced by reactions in our bodies. If it were allowed to build up it would kill us. Fortunately we have an enzyme in the cells in our bodies where hydrogen peroxide is produced called catalase. This enzyme catalyses the breakdown of hydrogen peroxide into harmless water and oxygen. Catalase is an antioxidant enzyme that, like superoxide dismutase (SOD) and glutathione peroxidase, is produced naturally within the body. It helps the body to convert hydrogen peroxide into water and oxygen, thus preventing the formation of carbon dioxide bubbles in the blood. Catalase also uses hydrogen peroxide to break down potentially harmful toxins in the body, including alcohol, phenol, and formaldehyde. We need oxygen to live, yet when our bodies use oxygen they produce free radicals that damage cell membranes, proteins, and DNA. Free radicals are chemically unstable atoms or molecules that cause other atoms and molecules in the body to become unstable as well, a process that causes extensive damage to cells and tissue, and could lead to a depressed immune system, infection, cardiovascular disease, joint disease, and mental decline. Free radicals are also thought to be a key component of the aging process. Catalase works closely with superoxide dismutase to prevent free radical damage to the body. SOD converts the dangerous superoxide radical to hydrogen peroxide, which catalase converts to harmless water and oxygen. Catalases are some of the most efficient enzymes found in cells; each catalase molecule can convert millions of hydrogen peroxide molecules every second. Hydrogen peroxide is a naturally occurring but destructive waste product of all oxygen-dependent organisms. It is produced in the human body when fatty acids are converted to energy, and when white blood cells attack and kill bacteria. Catalase, which is located in the cell’s peroxisome, prevents this naturally occurring hydrogen peroxide from harming the cell during these processes. It also helps prevent the conversion of hydrogen peroxide to hydroxyl radicals, potentially dangerous molecules that can attack and even mutate DNA. It has been theorized that one of the primary reasons cells age is the damage to DNA caused by free radicals and oxidizing agents such as hydrogen peroxide, and that elevating levels of the body’s natural free-radical fighters—SOD, catalase, and glutathione peroxidase—could both improve human health and increase human lifespan. Dr.Martin Chalfie and his colleagues at Columbia University found new evidence supporting this theory, when they recently discovered and isolated a gene in nematodes that uses catalase to neutralize free radicals and protect cells from oxidative damage. Mutating this gene to turn catalase production on and off increased and decreased the lifespan of the nematode accordingly. It may be that human aging, like that of the nematode, is a result of exposure to free radicals rather than the passage of time. Catalase, superoxide dismutase, methionine reductase, and glutathione peroxidase are all manufactured in the body. However, if you want to try to combat the effects of aging or ward off serious illness, you may want to supplement these enzymes.