Lesson from the pastThe chart below shows the survival rates – the percentage of the population that lives to a certain age – for men in England and Wales from 1860 to 2010.
In the 1860s, more than 20% of children died at birth or soon after. On average, men’s health started to decline around the age of 30, and only about 20% of the population survived for more than 70 years.
By 1910, child mortality decreased, thanks to improvements in hygiene and better medical care. This meant more men lived past the age of 50. Circle A shows this reduction in childhood mortality between 1860 and 2010. But, as can be seen from Circle D, the gain towards the end was not significant. This is because only 30% of males passed the age of 70.
Fifty years later, after the discovery of penicillin and invention of more vaccines, 90% of English and Welsh men lived until 50, and more than half survived to 70. Arrow B marks this trend.
Today almost 80% of men live to the age of 70. Four times as many men reach 70 now than in 1860.
What accounts for the change? Between 1860 and 1960, the significant increase in survival rate was due to medical intervention. Since 1960, the survival curve has improved mainly due to reduction in smoking.
This trend is similar in many rich countries, including the US. Druin Burch, a physician and writer, says in his book Taking the Medicine, that eliminating smoking would provide more benefits than being able to cure people of every possible type of cancer.
Age gracefullyMany experts believe that human lifespan might actually have an upper limit of 125 years. The average may not increase much beyond 90. If we are to agree with them, this leaves little room for improvement.
But we have never concentrated on maximising human lifespan before. Most people believe human lifespan is finite, so all drugs being manufactured today are targeted towards certain age-related diseases such as diabetes and hypertension. They are not designed to extend human lifespan.
If this bleak outlook is indeed true, we should not practise naive interventionism because it is unlikely to help. As Nassim Nicholas Taleb describes in his book Antifragile, naive interventionism occurs when we try to fix a single thing, but end up disturbing a complex system.
In case of extending human lifespan, those naive interventions would include calorie restriction, antioxidant supplements or manipulating the protein NF-kB, as mentioned earlier. They also include the current obsession with replacing fat in foods with sugar, the health benefits of drinking red wine, or the use ofsurgery or supplements to “fight” ageing. This latter industry has grown in the past decade from being non-existent to an estimated worth of $88 billion today.
If intervening in the ageing process with current biomedical science has any positive effect at all, it will be far too small to worry about. It’s far more likely to harm us.
That is why I have decided to do nothing and follow a simple rule: unless I meet with an accident, or suffer from a terminal disease, I will not add anything to my life with the explicit purpose of extending it. To do anything else would do more harm than good.