Non-Science Factors Influence Aging Theory Consensus

Aging TheoriesWHY is it that despite more than 150 years of effort there is still no scientific agreement on even the nature of human aging?  Is aging the result of fundamental limitations that could not be overcome by the evolution process, or a consequence of the lack of an evolutionary need for our ancestors to live longer, or the result of our possessing an aging program or biological suicide mechanism because populations of our ancestors received an evolutionary benefit from limiting individual lifespan? Many non-science factors act to bias thinking about aging and aging theories, mainly toward fundamental limitation theories or more recent non-programmed aging theories even though empirical evidence favors programmed aging theories. This is one of the reasons that no wide scientific agreement on even the nature of aging (much less details) exists today or is likely in the near future.

Education and Training

Most people are trained to believe Darwin’s individual-oriented evolutionary mechanics concept, which does not support more recent population-oriented evolutionary mechanics concepts and dependent modern programmed and non-programmed aging theories. Therefore they are, in effect, trained to believe in fundamental limitation theories. This logically leads to the idea that altering human aging is impossible. Very few of these people go on to obtain training in modern evolutionary mechanics concepts and dependent aging theories. Although modern non-programmed aging theories also conflict with traditional evolution theory, they do not present the gross and diametrically opposed conflict associated with programmed theories. The public is also accustomed to extravagant claims regarding discoveries and developments in medicine.

People who think that altering aging is impossible would logically be against funding research into anti-aging medicine or possibly even in studying aging on the basis that funds and other resources would be wasted. This situation also decreases motivation into studying age-related diseases and conditions. If aging is the result of fundamental limitations isn’t our ability to treat highly age-related diseases likely to be severely limited? Try comparing government funding of research on aging and age-related diseases to the defense budget. Now compare the death rates from age-related diseases to those resulting from enemy attack! We could ask the following question: Would funding for research into aging and age-related diseases increase if it was widely thought that aging, per se, was a treatable condition?

Anti-Science Influences

There are substantial anti-science influences at work in biology and medicine. Possibly the largest single anti-science effort currently extant is religious attacks against evolution theory. This effort strives to show that evolution theory cannot explain various observations without the intervention of supernatural intelligence and publishes pseudoscience articles to that effect. They then cite the pseudoscience in efforts to push teaching of anti-evolution religious concepts like creationism and intelligent design especially in introductory venues. This effort has been so successful that as of 2005 a Harris poll showed that the majority of Americans did not believe in evolution theory. Evolution is extremely central to the nature-of-aging issue and the anti-evolution situation leads to non-science biases toward fundamental limitation theories and non-programmed aging theories:

  • Proponents of fundamental limitation and non-programmed theories have, until recently, been able to dismiss programmed aging theories as non-scientific (and similar to anti-science proposals about evolution such as creationism and intelligent design) because of the conflict with traditional evolutionary mechanics.
  • Efforts to teach evolution, especially in more introductory venues like K-12 biology classes, would like to avoid any indication that there is any scientific disagreement regarding evolution theory and thus avoid giving support to the anti-science effort. This contributes to avoiding any mention of scientific disagreements about evolutionary mechanics or specific modern evolutionary mechanics theories.

The Zero-Sum Game

Funding for medical research tends to be rather flat (after inflation) on a year-to-year basis. Consequently, funding for new areas of research (like programmed aging or anti-aging medicine) must come from reducing funding to existing research avenues. Those researchers can be expected to fight fiercely against the new activities.

Scientific Inertia

Some senior bioscientists have a major public and long-term, even career, commitment to the older non-programmed theories. Such a person might well suspect that they are now betting on the wrong horse. However, for such a person to switch now would in many cases be like an Episcopal Bishop deciding to start over as an entry-level Methodist minister – possible but extremely unlikely.

Ethics and Health Policy Issues with Aging Theories

The fact that humans only live for a certain period is one of the most central and seemingly unalterable aspects of human existence and has profound ethical and policy implications. What happens to annuities, health insurance, pensions, social security, and Medicare if people start living significantly longer? What about the need for term limits for elected and life-time-appointed government officials? How do we increase retirement age? Would wealth imbalance increase?

Many have ethical concerns with altering aspects of human design that are “normal.” Most people would consider it unethical to genetically engineer humans to be taller, stronger, or more intelligent. It is certainly acceptable to the vast majority to attempt to treat or even cure cancer, heart disease, or other massively age-related disease because these conditions are not “normal” in that they do not occur in everybody. A very small part of the population does consider trying to treat cancer or other serious disease as interfering with God’s will and therefore sinful.

However, the more or less universal aspects of aging are certainly “normal” including “dying of old age.” Would it therefore be ethical to try to treat aging, per se? Worse yet, programmed aging theories suggest that humans possess an evolved suicide mechanism that limits their lifespans and that they are consequently designed to age. Aging is a feature of an organism’s design (like height) and not a defect (like a disease or injury).

On the other hand, just as it is obvious that different species age at very different rates, it is widely agreed that the aggressiveness of senescence, per se, varies substantially between individual humans. Therefore if a person inherited relatively aggressive senescence, should that person be able to seek medical aid to delay his senescence in such a way as to be able to enjoy a “normal” lifespan? Extending this idea, should we all be able to ethically enjoy the internally-determined lifespan seen by the longest-lived humans?

Many are concerned with medical advances that might extend the “nursing home stage” of life and favor advances that increase the “healthy” stage and decrease the nursing home stage.

Because they are concerned with the policy, ethics, and religious issues, some are against development of medical technology that would “extend normal lifespan” and are consequently against research in directions that might support lifespan extension – including programmed aging research, and even possibly including research as to the nature of aging such as initiatives specifically designed to determine if aging is programmed or not programmed. Some consider that because aging is a natural and normal aspect of human existence it is not a proper subject for medical research and medicine should be confined to treating dysfunction.

My conversations with thoughtful members of the general public indicate that there is substantial concern over these issues. Informal polling suggests that more than half of the U.S. population has at least some ethics, moral, or policy issues with research into lifespan extension or altering aging.

There is no doubt that senescence is surrounded by serious health policy, ethical, and religious issues. However, in my opinion it does not make logical sense to spend billions on research into treating massively age-related diseases without understanding aging and that doing so amounts to a “fool’s errand.” How can we hope to understand and best treat such a disease without understanding aging? If the majority of deaths due to highly age-related diseases (even in 40-year-olds) are caused by aging, how can we ignore aging in devising treatments for these diseases? Senescence is what it is. Ignoring scientific evidence pointing toward a certain conclusion regarding aging mechanisms is like ignoring global warming or ignoring all the evidence that the Earth orbits the sun.

Average human lifespans have substantially increased in the last century and few would really like to return to a much earlier age. Is it likely that there is going to be such a sudden and large increase in human lifespan that there would be huge social upheaval as a result?

Conclusion: A substantial portion of the U.S. population has issues with research into interfering with human biological aging mechanisms because they think such interference is impossible or because of ethical, religious, or policy issues. These attitudes obviously impact funding and support for research into aging and age-related diseases.

Aging Theories Articles Index

 

Aging Theories in the Academic Gerontology World

Aging TheoriesThinking about theories of aging in humans and other mammals in the academic gerontology and more general bioscience community now centers around two concepts: Aging (and an organism-design-limited lifespan) is genetically programmed and an adaptation because limiting lifespan created an evolutionary advantage, or, it is not. Opinions in the gerontology community tend to be highly polarized on this issue.

Members of the programmed aging faction tend to think that current published science overwhelmingly supports programmed aging.

Many members of the non-programmed faction consider programmed aging to be scientifically ridiculous because it conflicts with evolution theory as generally understood. Some non-programmed proponents have compared programmed aging to popular but scientifically ridiculous concepts about evolution such as creationism and intelligent design. Non-programmed aging is still more popular in the academic community and general science-aware public but programmed aging provides a better match to empirical evidence.

Life in the academic world is very public; we could say “publish or perish.” The scientific journal system including peer review is widely seen as necessary to maintain scientific integrity, especially for articles describing experimental or observational results and procedures. However, the system is less amenable to theoretical work. The “peer” review process tends to work against publication of new or unpopular ideas and some gerontology journals effectively will not accept articles that favorably describe programmed aging. Gerontology journal editorial boards are usually staffed by senior people who tend to follow older theories, in this case non-programmed theories, and often contain dedicated proponents of and even authors of non-programmed theories. This creates a rather hostile academic work environment for one considering performing research in programmed aging. Publicly declaring a belief in programmed aging could well amount to career suicide if one’s boss or institution thinks that programmed aging is “nuts.” Few researchers can afford to follow such a path.

In addition, the vast majority of the science-aware general public has essentially been trained to believe in non-programmed aging. No institution wants to be seen as performing research that is widely seen as scientifically ridiculous. Funding sources do not want to be seen as funding junk science.

Only a few research institutions publicly support the idea that human aging is genetically programmed because such a design created an evolutionary advantage. One such is Moscow State University.

This creates a situation where some researchers are performing research that does not make any sense under non-programmed theories but scrupulously avoid controversial terminology such as “programmed aging” or worse yet “suicide mechanism.” One sees creative ways of “finessing” this issue such as journal articles with titles along the lines of “Semi-programmed non-programmed aging.”

Nobel-prize-winning physicist Max Planck famously said: “A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it.”  Younger researchers are more likely to follow programmed aging concepts.

One workaround for the journal problems that has proved successful is for a journal to host a special issue to specifically compare opposing schools of thought, in this case programmed vs. non-programmed aging. Authors for both sides can then be assured that their review is going to be performed by someone who is in their faction and that therefore rejection is not preordained. In addition this creates a useful “shoot out” context where readers can compare multiple pro and con arguments. See example [1]. Note that this requires the journal to concede that programmed aging has attained a level of scientific plausibility that at least justifies serious discussion. Some journals (like Elsevier Medical Hypotheses) are specifically designed to allow reviewed publication of unpopular theories using a modified review process.

Until about 2005 many senior gerontologists dismissed programmed aging as ridiculous and “impossible” without providing any attempt at serious rebuttal or refutation of arguments and claims by programmed aging proponents. However, some senior non-programmed proponents now concede that programmed aging is possible “under certain circumstances’ and are arguing details, a significant change in attitude [2].

NIH PubMed now (Jan 2018) shows 1323 articles in a search for “programmed aging.”

Conclusion: No one would be surprised if the endless academic arguments regarding the programmed vs. non-programmed nature of aging continued for another 150 years! However, venues for publication of programmed aging articles are increasing and the programmed aging faction is growing in size, popularity, and impact. The research environment in the commercial world (e.g. pharmaceutical companies) is much more favorable to programmed aging as will be discussed in a companion article.

[1] Current Aging Science Vol 8 Nr1 Programmed vs. non-programmed aging, 2015, Libertini G. ed. open access

[2] Curr Biol. 2011 Sep 27;21(18):R701-7. Kirkwood TB, Melov S. On the programmed/non-programmed nature of ageing within the life history.

Aging Theories Articles Index

Medical Implications of Aging Theories

Aging TheoriesAs can be seen from the figure (U.S. mortality data), human death rates from all causes in developed countries increase exponentially starting at about age 30 and doubling approximately every ten years. We can define age-related disease or condition as one where the incidence and severity drastically increase with age to the point where aging is by far the main cause. Massively age-related diseases include heart disease, stroke, cancer, arthritis, cataracts and other vision deterioration, hearing loss, and loss of strength and balance. Alzheimer’s disease is essentially unknown in young people. Death rates for 40-year-olds are approximately twice the rates for 30-year-olds so we can consider that nominally half of deaths in 40-year-olds are caused by aging along with three-quarters of deaths of 50-year-olds and so forth. Aging and age-related diseases cause about three-quarters of all deaths in developed countries and represent more than half of medical research and health-care costs.

There is wide agreement that there are different immediate or direct causes associated with each age-related disease and condition. The immediate causes of heart disease are not the same as the causes of cancer or the causes of arthritis, etc. Western medicine is largely based on the idea that we need to find different treatments and pharmaceutical agents to treat different diseases and conditions. This approach has obviously been substantially successful in treating age-related diseases.

The current trillion-dollar question is whether or not aging, per se, although obviously the main cause of the age-related diseases is itself a treatable condition. If so, treatment of aging could be used in parallel with the existing medical paradigm in our efforts to treat age-related diseases and conditions. As described below, different aging theories suggest drastically different answers to this question.

Fundamental limitation theories, wear and tear, stochastic, etc. strongly suggest that aging is an untreatable condition. We can find treatments for individual symptoms such as cancer and heart disease but we cannot find ways to treat aging, per se, as it is the result of fundamental limitations that could not be overcome by the evolution process and are very unlikely to be overcome by medical advances.

Modern non-programmed aging theories suggest that aging is not the result of fundamental limitations but rather the result of a large number of different independent factors as explained by George Williams in 1957. Unlike inanimate objects, living organisms obviously have many biological mechanisms for repairing or preventing damage. Wounds heal; dead cells are replaced; immunity is acquired, and so forth. Therefore humans and other organisms reasonably would have developed biological mechanisms to delay the appearance of cancer, other methods for dealing with the different damage mechanisms associated with heart disease, and myriad other mechanisms for delaying the occurrence of other age-related diseases and conditions.

This concept explains why different mammals have such different internally determined lifespans while having very similar biochemistry and similar symptoms of aging. This idea assumes that all of the different maintenance and repair mechanisms each presumably independently evolved and retained just the effectiveness needed to deliver the minimum necessary species-specific internally-determined lifespan called for by modern non-programmed theories based on Medawar’s evolutionary mechanics ideas.

These concepts support the accepted idea that we can find different ways to treat each specific age-related disease. However, these concepts suggest that there is some ultimate age beyond which further progress in extending human lifespan would cease because eventually every aging symptom would appear at catastrophic levels. They further suggest that there is no treatable common factor behind age-related diseases and conditions. These theories therefore support the current medical paradigm of ever-increasing specialization by disease, disease sub-type, and even personal disease variety.

Modern programmed aging theories suggest that a second path toward combating age-related diseases and conditions exists. These theories propose that the age-related diseases and conditions are coordinated by a biological aging program that stages the appearance of aging symptoms to result in a particular optimum lifespan for each species population. In addition to finding better ways to combat each particular disease we can look for ways to interfere with the aging program and therefore generally delay or reduce the severity of age-related diseases especially in older individuals. If valid, this is an exciting development because two different approaches can be used against age-related diseases. Because the anti-aging approach is new, we could reasonably expect “low hanging fruit” and rapid progress.

The effectiveness of an attempt to interfere with the aging program depends on one’s concept of the nature of that program and specifically the degree to which the program is common to the many age-related diseases and conditions and the extent to which the common program can control each symptom. For example, if senescence is controlled by a program similar to the one that controls mammal reproduction, and aging is a genetically programmed phase of life, then we could expect rather dramatic results. If we wanted to delay or advance puberty that would certainly be possible. There is considerable theoretical thinking and empirical evidence suggesting that, like reproduction, aging is controlled by a complex common program involving signaling (hormones).

There is fairly wide sentiment to the effect that aging can be generally delayed by exercise and perhaps by caloric restriction. This idea conflicts with non-programmed “damage” theories because exercise and caloric restriction would be expected to increase, not decrease, damage. Many other observations support programmed aging.

For more discussion of the nature of the aging program and supporting evidence see:

Externally Regulated Programmed Aging and the Effects of Population Stress on Mammal Lifespan

Aging Theories Articles Index