Eternally young: the billionaires seek the elixir of eternal youth

The geroscience aims to understand the processes associated with human aging in order to design mechanisms to circumvent the senescence of cells and organs. Aging is a normal physiological process, but if we could unravel the mechanisms that regulate it, perhaps we could extend our lives. This is an attractive principle that receives public but especially private investment, as people with many resources wish to live for many years.

Altos Lab, created by billionaires like Jeff Bezos (founder and CEO of Amazon) along with venture capital, is totally private, has several Nobel laureates as advisors, and has hired highly recognized researchers in the scientific world on a full-time basis, to whom it has given complete freedom to create innovative medicines for rejuvenation. We also find influencerare impatient with scientific advances and biohackers who engineer their bodies to change the course of aging, such as Bryan Johnson, a former businessman who has been self-medicating for years to extend his life, and about whom documentaries can be found on social media about the cocktail of drugs he takes (or has taken). Among his eccentricities are periodic blood transfusions from his teenage son in order to "cleanse" his blood. For more than six years he also took metformin in different doses, but he has just confessed that he has stopped because the side effects on his health – including recurrent infections and fatigue – showed him that perhaps it was not the magic pill he was looking for… Because let's not kid ourselves, these millionaires are not looking to live many more years, but to be eternally young.

Is there a life expectancy limit?

We have all heard that human life will be extended as a near certainty in time. One of the most used arguments is that we have already extended it in little more than a century. And it is true that in many European countries it has doubled, but this growth is not exponential. We have reached a situation of very limited increase. Even in some countries, such as the United States, it is decreasing due to the increase in obesity and diabetes in a large part of the population, which causes serious health problems and a reduction in quality of life. On the other hand, generalized optimism does not distinguish between the maximum longevity of the species and life expectancy. Life expectancy is the prediction of the lifespan that an organism has at birth, and in the case of humans it has increased considerably due to the decrease in infant mortality, access to drinking water, advances in hygiene and surgery, and, above all, thanks to antibiotics and other drugs that treat all kinds of infectious diseases, cardiovascular problems, diabetes, or cancer.

There is considerable scientific evidence demonstrating that, in animals with short life cycles – the vinegar fly, nematodes, or mice – interfering with calorie intake – caloric restriction – or with the body's use of the main cellular energy source, glucose, such as with metformin or Ozempic-like drugs, extends the lifespan of these organisms. However, it has never been demonstrated that the determinants of maximum longevity in our species are the same as in these animals. Clearly, a mouse is old at two years and dies with symptoms associated with aging, but at two years of life, we are still little more than infants in development.

It should be noted that drugs that interfere with glucose use in our tissues are prescribed (or should be prescribed) in a clinical setting. In case of illness and when there are metabolic alterations, the risk-benefit ratio clearly favors medication with appropriate drugs and medical supervision. From this, however, it does not follow that consuming these medications has a beneficial effect on all people, quite the contrary: every drug has very potent active ingredients, with sometimes unforeseen or undesirable side effects. Even if the price to pay is not immediate, interfering with glucose metabolism in a healthy person can lead to serious health problems later on, although we do not yet know for sure – these drugs have existed for too short a time to know their long-term effects.

Rejuvenate body parts

Many scientists, aware of the difficulty of trying to extend human longevity, prefer to set closer and potentially more achievable goals, such as rejuvenating certain parts of the body. That is, perhaps it is not as important to live many more years as it is to live them as if we were younger, rejuvenating our bodies. Regenerative medicine has received a great boost since the beginning of the 21st century, with the generation of induced pluripotent stem cells (iPSCs), cells from an adult person that have been reprogrammed to "become" embryonic, true stem cells that can differentiate into specific tissues and mini-organs, organoids of kidneys, brains, or retinas… There are already publications demonstrating that we can generate a kind of cell strips to repair hearts that have suffered a myocardial infarction or to restore sight to people with blindness. This path of organ rejuvenation will be possible, but at a very high cost, and it must be remembered that rejuvenating an organ does not mean being younger overall.

We now have more centenarians than ever before, but the maximum longevity of the species has not increased by even one year, it remains around 122 years. Will we be able to change the limits of human longevity? We will address the answer to this question in another article.