HOW LONG CAN WE LIVE?
The dream of immortality or at least extending life span is probably as old as humanity itself. While immortality evidently remains a dream, average life expectancy has improved over time. It is estimated that average human life expectancy was below 30 until about 30,000 years ago. But it would appear that until the 19th century, it was not much above 30 to 40 years. Only from the early 1800s did people (e.g. in Europe) on average live longer generation by generation.[1]
On a global level, the average life expectancy at birth currently sits at around 73 years (both sexes), while the highest life expectancy at birth can be found in Hong Kong, with over 85 years (both sexes).[2]
Yet, we all face the realities of the ageing process. The World Health Organization describes ageing as follows: “At the biological level, ageing results from the impact of the accumulation of a wide variety of molecular and cellular damage over time. This leads to a gradual decrease in physical and mental capacity, a growing risk of disease and ultimately death.”[3]
There are, of course, notable differences between individuals, and biological age does not necessarily mirror the chronological age of a person; however, the effects of growing older eventually catch up with everyone who lives beyond 30. That has been the common wisdom until recently.
Extending our lifespan
That is not to say that scientists did not spend time and energy on breaking the mold, trying to understand the phenomenon of ageing. The idea that interventions could change the lifespan of an organism came into play only in the last 100 years or so. One of the interventions is called Caloric Restriction, where it was shown that an organism’s reduced calorie intake results in a longer lifespan compared to unrestricted feeding. In the 1980s, studies demonstrated that genetic modifications, e.g. in worms, can activate certain pathways that impact longevity.
Also, some drugs, originally designed for other medical purposes (for instance Metformin and Rapamycin) have been studied with regard to their abilities to extend an organism’s life span.[4] But now science seems to start telling a markedly different story about the process of ageing. So, are we on the verge of an exponential increase in life expectancy, on an individual and population level?
Recent scientific progress
Recently published scientific evidence points towards pathways to significantly increase life expectancy by slowing ageing or even reversing the process of ageing. In addition, more scientific knowledge has been developed that tells promising stories about how we can avoid serious, life-threatening diseases such as cardiovascular disorders or malignant growths.
I am referencing chiefly two areas of scientific progress, represented by David Sinclair, a professor at Harvard Medical School and David Perlmutter, a neurologist and prolific medical writer. Sinclair, in his popular book Lifespan (Sinclair, David A, Lifespan: Why We Age, and Why We Don’t Have To, Atria Books 2019) explores ways of pushing the boundaries of longevity, based on laboratory findings and self-experiments. David Perlmutter in his recent book Drop Acid (Perlmutter, David, Drop Acid: The Surprising New Science of Uric Acid―The Key to Losing Weight, Controlling Blood Sugar, and Achieving Extraordinary Health. Little, Brown Spark, 2022) discusses the – in his view – underestimated role of uric acid in biochemical processes and the highly beneficial effects of keeping uric acid in our body at a desirable level.
Both these areas of research set their sights on reducing the risk of disorders typically encountered by an ageing individual. One comes more from a genomics-related angle, while the other puts metabolism at the center of the narrative.
In a nutshell, Sinclair argues that ageing is not an inevitable fate for human beings (or other living creatures for that matter) but should be considered a disease. This disease can be addressed by a mix of supplements, tackling the accumulative damage to our genome and epigenetic functions, and lifestyle changes. Sinclair likens the aged genetic information to a scratched CD and points out that these scratches can be repaired on a molecular basis, offering the necessary building blocks to start and maintain the repair process. But equally important seems to be to invigorate the repair processes by exposing the body to challenges such as hunger, cold temperatures, strenuous exercise, all mimicking threats to survival, to which the body reacts by activating survival mechanisms on all levels including the genes and the epigenetic controls.
Perlmutter proposes a theory that puts uric acid at the center of the causation of many serious health conditions. The common view is that uric acid, a waste product of metabolic processes, can cause gout, a painful formation of crystalline structures in joints, if and when it is elevated. This view is dwarfed by increasing evidence that too much uric acid in the bloodstream can act as the generator and accelerator of disease-causing processes in many different organs and tissues. The underlying chemical pathways often are complex and sometimes not even perfectly understood, yet studies show that reducing uric acid to levels that ideally are on the low side of what is now considered the normal range, are able to readjust those pathways and prevent severe health outcomes. Nutritional interventions and supplements can control uric acid levels in a relatively easy fashion.
Implications
Of course, in both the genomic and the metabolic aspects of ageing, more research is required to underpin and corroborate the evidence accumulated so far. In particular, larger clinical studies would be helpful to make sure laboratory and small study findings can be reproduced in cohorts representing a wide range of the general population. But if that can be done, then we could be on a trajectory, where a life span of 120, 150 or even more years (with disease burden concentrated on the final months of life) seems entirely possible.
These developments obviously would have major and wide-ranging implications for societies and consequently the insurance sphere. Life and Health insurers would need to rethink their products and pricing, just as some insurers have done in the past, where for example in Hong Kong the acknowledgement of a generally higher life expectancy has led to an extension of coverage age from 100 to 120 for certain products.[5] But what about Workers Compensation, when people want to and are perfectly able to work at much higher ages than they do now? How about Motor Insurance, when people want to and are perfectly able to drive a car at much higher ages than what we see now? And the list probably goes on …
So let’s watch this space!
At this point in time though, it is probably fair to say that the easiest and most accessible way of pursuing a longer life is to follow a healthy diet and engage in sufficient physical exercise.
[1] A Guide to Longevity Throughout History, verywell health, https://www.verywellhealth.com/longevity-throughout-history-2224054#citation-3
[2] Life Expectancy of the World Population, Worldometer, https://www.worldometers.info/demographics/life-expectancy
[3] Ageing and health, The World health Organization, https://www.who.int/news-room/fact-sheets/detail/ageing-and-health
[4] History of Aging Research, Colorado State University, 21 February 2022, https://www.research.colostate.edu/healthyagingcenter/2022/02/21/history-of-aging-research/
[5] See for example, People living longer lives sees HK insurers update their policies, Insurance Business Asia, 16 August 2016, https://www.insurancebusinessmag.com/asia/news/breaking-news/people-living-longer-lives-sees-hk-insurers-update-their-policies-49696.aspx
