Why study aging and not something else?

(unfinished placeholder post for the future)

Studying and targeting aging is the most efficient use of resources

One day I hope that every highschool biology textbook will have a page dedicated to the biology of aging. Here I would like to explain why it should be so.

The 20th century brought unprecedented prosperity and well-being for many. Average life expectancy saw a dramatic increase doubling globally from 32 to 66 years, settling somewhere around 80 to 90 years in developed nations. Indeed, life expectancies in developed nations are so high now that the rate of aging has become the limiting factor for human health- and lifespan.

This brings us to the most important scientific study you have never heard of and the most important paradox in all of medicine that is rarely discussed. I am not even exaggerating, not one bit. It was in 1977 when Nathan Keyfitz drew attention to a demographic fact that became known as the Taeuber paradox. Although I am sure the literature on this dates back to pre-70s, this is the eponymous paper that gave the idea a name. Keyfitz wrote those pithy lines that you should never forget: "What difference would it make if cancer were eradicated? An examination of the Taeuber paradox".

To understand the answer to this question, we must think in the following terms. Most diseases of the elderly are directly caused by aging and due to “competing age-related risks” for these various diseases the eradication of any one disease would only have a surprisingly small benefit. Put in the simplest way, if cancer does not kill you so will cardiovascular disease (Olshansky et al. 2016; Keyfitz 1977). This necessitates a totally new approach to health and longevity provided by modern aging research.

Already in the 70s Keyfitz went on to answer the question that eradicating all cancer - a monumental, unprecedented feat - would do almost nothing to advance human lifespan and, as it turns out, very little to improve healthspan.

The implications of this are so serious that it is worth digesting every syllable of his thesis. I know it is shocking to see a long-upheld worldview crumble, but the truth is that most of the disease-centered medical research we are doing in the developed world to target age-related diseases (in contrast to diseases of e.g. poverty) is running into a wall; our research is close to useless because it will fail to extend human lifespan and healthspan (1). Only when we target aging directly to slow all dozens or hundreds of age-related diseases at once will be able to improve the human condition. In fact, it is very possible that the Taeuber paradox is at the heart of Eroom's law, as pharma companies were forced to slowly shift towards addressing age-related diseases, while still using the old disease-centric tools.

This phenomenon is widely known among aging researchers but not often by this name. It is important to attach a name to an important law because it makes it easier to remember. This is the most important fact in all of modern medicine and it must be remembered.



Studying and targeting aging is ethical

Everyone ages and many of us - those lucky enough - grow old. Unfortunately, aging leads to a lot of suffering whether as a consequence of age-related diseases directly impairing quality of life or due to the loss of a loved one. If we could slow aging then we would reduce the amount of suffering per unit of time. We know from human and animal studies that those who live longer generally spend a larger part of their life in good health. There is no "law of symmetry" suggesting that an extension of lifespan has to be fully offset by an extension of suffering at the end of life. Lifespan extension is a pure good in a chaotic world.

Even if you consider the health of the environment and the planet as a factor, it is better to extend human lifespan rather than shorten it. Only people who have a real stake in the future will care about long-term problems like climate change.

We all deserve the choice to live our life the way we want to.

Our goal is to extend human lifespan by one year, then another, and another. There is no limit, there is no law saying we cannot or should not continue to extend human lifespan. Any amount of lifespan extension no matter how small, as long as it was achieved by slowing the intrinsic rate of aging, will have enormous benefits to the taxpayer and to everyone growing old. We will try to extend human lifespan as much as possible. One has to be realistic, one has to have dreams and one has to have longterm goals.

References

1. As stated this limitation does not necessarily apply to diseases of poverty like e.g. Malaria, worm infections, HIV, etc because they are per definition cheap to target, since they occur in resource poor-countries that are constrained by their limited budgets and because they usually afflict children and adults of all ages. There are many unexplored implications as well. One creative way of breaking out of (or ignoring) Taeuber's confines, in developed nations, is to target mental diseases and the hedonic steady state, because these issues afflict people of all ages and because they target a completely orthogonal problem (i.e. the fact that no matter how objectively useful a treatment is, no matter how good or bad our life, the brain tends to return to some sort of hedonic setpoint; basically this is the concept of the hedonic treadmill).

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