Life expectancy in India has crossed 70 years. It is slightly higher for women and lower for men. However, many older people complain that “they do not want to live any more”. They feel they are a burden on their families, or their health is terrible, and each dull day feels like a million years.

There is a lot of information in the media about how to live beyond 100 years. Supplements are advertised, diets are encouraged and oils, hot baths and massagers are sold. It is a very profitable industry.

More importantly, we all age; we must try to age healthily. If you do these things, you will not feel the years creeping up on you.

It makes sense to try and postpone or hopefully, prevent lifestyle and age-related diseases like diabetes, hypertension, heart disease, dementia and even certain cancers. But is this possible?

Our genetic makeup is inherited from our ancestors and present from conception. However, as we grow and age, our cells are not static. Cells die and replicate. And as they do so, the genetic DNA is passed on from one cell to another. For example, when we copy and paste on the computer, a letter or two may be inadvertently missed, or the alignment may differ. When cells divide, the ends of some of the chromosomes may break off, and some may be imperfect or incomplete.

Environmental poisons may aggravate and hasten many of these defects. Exposure to ultraviolet rays (avoid excessive sunlight exposure), microplastics in food and drink, cigarette smoke, alcohol, trans fats in food and pesticides act adversely on cells.

Imperfect cells may be responsible for tumours and cancers. The body usually removes bad cells to prevent this, but the efficiency of the process decreases with age. So many damaged cells may be produced if the body’s defence mechanisms are overwhelmed.

Sometimes, the DNA becomes so damaged that the cell population itself decreases, like when hair stops producing pigment and turns grey or baldness sets in. Our skin also tends to become dry and lose its elasticity, bones become shorter, and nails grow more slowly.

Cells function because of enzymes and proteins. As genes become faulty, these products also get affected, and “bad, defective and non-functional” proteins build up in cells and the body. Only small amounts of these proteins are formed in young people, and the body disposes of them. This process is less efficient in older people. These proteins build up and cause age-related diseases like Alzheimer’s.

Research is being done on medications to prevent these processes. So far, medication has only been tested on worms and mice. It will be many more years before the results can be projected onto humans.

The writer has a family practice at Vellore and is the author of Staying Healthy in Modern India. If you have any question on health issues please write to yourhealthgm@yahoo.co.in