How We Grow Old
The air we breathe contains essential oxygen in a mixture of other gases. The lung is the organ which separates oxygen. But before it ultimately gets absorbed into the blood, it passes through a lesser known phase called the redox state. Any disturbance or imbalance during this process can lead to a harmful state called oxidative stress. Substances called antioxidants present in our body ensure that this state is always in check. When with the passage of time, the production of these substances declines, oxidative stress leads to aging in humans. This article tries to understand how we age.
Basics required to understand the aging process:
What are Chemical reactions?
We are all, being part of nature, made up of atoms and molecules. Collections of atoms form a molecule. An atom has a nucleus at its center. Inside the nucleus, there are particles called protons. Another particle called an electron, exactly equal in number to the proton, resides outside the nucleus. Protons are all inside the nucleus. Electrons revolve around the nucleus. We can imagine the atom to be like our solar system, the nucleus being the sun and the electrons revolving around the nucleus like the planets. Chemical reactions are primarily the exchange of the electron particles from one atom to another reacting atom.
What happens when we inhale oxygen?
When oxygen is inhaled it interacts with the atoms and molecules present in our body. The interaction can take place in two ways. An atom can combine with the oxygen, by giving up its electrons to the oxygen as part of the chemical reaction. This is called the oxidation process. Similarly, it can lose the oxygen atom by gaining electrons from the oxygen. This is called the reduction process. Oxidation-reduction reactions together are called redox reactions. Ultimately, the substances involved share the electrons in such a manner that the number of electrons lost by one substance is equaled by the number gained by another substance. Molecules called enzymes present in the body help in carrying out this process.
The Process of Aging:
What is Oxidative Stress? Any disturbance during the transfer of electrons during redox reactions can lead to the availability of unclaimed electrons and positive ions. Atoms that no longer contain equal numbers of protons and electrons in them turn into ions. The loss of electrons from the atom increases the number of protons in the atom, turning it in to a positive ion. Positive ions and unclaimed electrons that occur during redox reactions are called free radicals. They can cause harmful effects to our bodies by damaging body cells. A condition where free radicals grow at an uncontrollable rate is called oxidative stress. It causes heart failure, Parkinson’s disease, Alzheimer’s disease and chronic fatigue syndrome to name a few.
Antioxidants and their role in Oxidative Stress:
An antioxidant is a molecule which can prevent the process of oxidation. These molecules do not allow the transfer of electrons from an atom to an oxygen atom. In this way the cascade of free radical production is terminated. The natural antioxidant in our body is the “superoxide dismutase (SOD)”. Its primary aim is to protect the cells of our body when they are exposed to oxygen. As we grow older, the production of this vital antioxidant molecule decreases. Low levels of antioxidants enhance the process of oxidative stress leading to aging.
The fruits and vegetables we eat contain antioxidants. So, the natural decaying of antioxidants in our body can be deferred by the regular intake of fruits and vegetables. This further delays aging.