Free radicals are uncharged molecules with unpaired electrons in their outermost valence shell. Free radicals are by-products of chemical processes such as oxidation and all oxidation processes occur via a free radical mechanism. The body’s ability to release energy from the food we eat and the oxygen we breathe occurs by an oxidation process called oxidative phosphorylation. This all happens inside our cells in the mitochondria, which are the powerhouses that drive our metabolism and bodily functions.
The free radicals produced from oxygen are termed Reactive Oxygen Species (ROS). A small amount of ROS are good for our cellular function and are used as weapons by our immune system to fight off infections. However, they need to be kept to a low level, otherwise they will damage our own cells by causing oxidative stress. During oxidative stress, the ROS run rampant damaging all cellular components from nucleic acids (e.g. DNA), proteins and lipids. It is for this reason that every cell must have its own supply of glutathione. It is glutathione’s job to neutralise these ROS and prevent oxidative stress.
In many poisonings (e.g. heavy metals and acetaminophen overdose), the glutathione in our cells (particularly those in the liver) is rapidly (acutely) depleted. This occurs if our cellular capacity to produce glutathione is overrun by the onslaught of free radicals generated by the poison or overdose.
During ageing and in many chronic conditions, the affected cells have lost the ability to make enough glutathione to manage the free radicals to a safe level. This leads to progressively worse damage and ultimately the loss of physiological function, where we become ill and show the symptoms.