Life extension is defined as prolonging human life beyond the normal limits of roughly 120 years. There is some evidence that demonstrates this is possible. Research shows that aging can be delayed in experimental animals, sometimes manyfold. Science is increasingly able to repair damage to the body, replace damaged organs, and modify genetic makeup to extend life spans.
Sharing the blood of a young animal has been shown to rejuvenate older animals and prolong their lives. Substances like NAD (nicotinamide adenine dinucleotide) and rapamycin can improve mitochondrial function genes associated with aging.
Many authorities are confident that human life can be meaningfully extended. Ray Kurzweil forecasts that life extension treatments are likely to become available before 2030. Aubrey de Grey of the U. of Cambridge believes the first person who will live to see his 150th birthday has already been born. Some think the first person to live for 1,000 years will be born in the next two decades.
But many therapies only stretch normal aging to the 120-year limit, rather than extending life spans beyond those limits. For instance, a respected medical journal, The Lancet, projected that most babies born since 2000 in industrialized nations will live to celebrate their 100th birthday.
Some scientists doubt that life extension is possible beyond a theoretical maximum of 120 years. S. Jay Olshansky, professor of public health at the U of Illinois, once pointed out, “There are no interventions that have been documented to slow, stop, or reverse aging in humans.” Yet Olshansky later writes, “It is only a matter of time before aging science acquires the same level of prestige and confidence that medicine and public health now enjoy, and when that time comes, a new era in human health will emerge. …the 21st century will bear witness to one of the most important new developments in the history of medicine.”
While the number of centenarians has increased dramatically, the number of supercentenarians (people living 110 years) has failed to keep pace. The number of centenarians worldwide is about 450,000, yet there are only 300 to 450 supercentenarians. Ned David, president of Unity Biotechnologies, says his company does not expect people to be living to 150 years and has chosen to focus on improving the “healthspan” rather than increasing lifespan. The concept of “healthspan” arose largely in response to priorities at NIH, which does not consider aging to be a disease. Research to extend lifespan does not get funded. Research to extend healthspan does.
Others contend that many apparent breakthroughs from animal research (resveratrol, antioxidants, etc.), like their counterparts in cancer treatment, have proved ineffective in humans. In mid-2021, there is little if any sign of actually extending normal human life spans.
The challenges and consequences of increased life spans could be enormous. If serious life extension does prove feasible, there remains the fear that longer lives will simply prolong poor health and feeble minds rather than adding capable years. Political scientist Francis Fukuyama warns that society may soon “resemble a giant nursing home.”
Jose Cordeiro’s new book, The Death of Death, has been published in several languages and is very optimistic about life extension. Cordeiro notes:
“A group of scientists under the direction of Spanish biologist María Blasco, director of CNIO (the Spanish National Cancer Research Centre) in Madrid, has created the so-called Triple mice, which live approximately 40% longer.[i] With totally different technologies, other scientists such as the Spanish Juan Carlos Izpisúa, an expert researcher at the Salk Institute for Biological Studies in La Jolla, California, have also been able to rejuvenate mice by 40%.[ii]”
“In 1993, Kenyon and colleagues found that mutations in the gene daf-2 increases the longevity of C. elegans hermaphrodites by more than two-fold compared to wild type nematodes.”
Earlier studies by TechCast estimated that useful medicines and other anti-aging treatments are likely to enter markets about 2028 +/- 4 years. This would lead to a commercial market of roughly US$600 billion at saturation about 2040. The experts were 58% confident in this forecast.
Research and Treatments on Aging
Genetic defects that cause aging are being resolved and drugs have been found that could delay the process. For example, the common diabetes-Type 2 drug metformin has shown experimental promise in slowing processes related to aging. Below are some recent developments:
Why People Live Past 110 Researchers are beginning to decipher the genomes of supercentenarians (those aged 110 and older) for clues to longevity. The late Dr. Stephen Coles, of the UCLA Gerontology Research Group, found that a condition known as cardiac amyloidosis ends the lives of supercentenarians. He and his colleagues identified drugs that might extend lifespan by preventing or curing that malady.
Repairing Bodily Damage Various methods are emerging to repairs damaged organs, tissues and cells. A TechCast study forecasts that almost all body parts should be replaceable in years to come, including the heart, kidneys, eyes, blood, limbs and parts of the brain. Nonotechnology promises to use fleets of nanobots to clean up cell damage and other cellular flaws. Additionally, CRISPR technology increasingly allows genetic rewiring to eliminate genetic defects and chronic diseases. If this can be done thoroughly, the body can in principle be continually updated to last indefinitely.
- Studying yeast cells, researchers have demonstrated that a three-to-fivefold reduction in DNA errors results in a 20 to 30 percent increase in lifespan.
- Experiments with fruit flies have shown that tampering with genes can slow aging and extend life spans. One possible target is aging stem cells, which limit normal tissue maintenance and regeneration. Gene therapy in animals prevented this aging decline.
- Harvard’s George Church thinks genomic engineering is now beginning to recode DNA germline cells to avoid disease and enhance health. He believes the 170-year-old trend in which life spans increase by three months each year will accelerate dramatically. Church has successfully trialed age reversal in mammals and expects to start human trials by 2030. He recently said: [iii]
“Probably we’ll see the first dog trials in the next year or two. If that works, human trials are another two years away, and eight years before they’re done. Once you get a few going and succeeding it’s a positive feedback loop.”
- Craig Venter, the co-founder of Human Longevity, Inc., claims that DNA sequencing can predict lifespans and also suggest targets for therapeutic treatments and life extension.
- Israeli researchers have developed an algorithm that predicts which genes can be “turned off” to create the same anti-aging effect as calorie restriction. Caltech scientists have found a way to eliminate nearly all genetic damage in mitochondria, a major cause of aging.
Sharing Blood Linking the circulatory system of an old animal to that of a young one rejuvenates the aged partner and sometimes extends its lifespan. Aging mice given blood plasma from young humans regain the mental abilities of much younger mice. Scientists now starting human tests of compounds from young blood that they believe could improve health in the elderly. Two, called GDF11 and Klotho, seem promising
NAD Anti-Aging Pill Researchers from MIT are marketing nicotinamide adenine dinucleotide (NAD), which duplicates the benefits of calorie restriction diets, the most widely successful life-extension treatment yet discovered. “NAD is one of the most exciting things happening in aging,” said Nir Barzilai, director of Albert Einstein College of Medicine.
Chromosome Length Studies show that the shortening of chromosome ends (telomeres) decreases lifespan. Researchers at Salk Institute have found an on/off switch for telomerase, and mice treated to maintain telomere length improve age-related disorders.
Rapamycin “Rapamycin has been shown to extend life span in lab animals again and again and again,” says U of Washington scientist Matt Kaeberlein. Novartis has licensed a derivative of rapamycin to PureHealth’s start-up company resTORbio. A recent article confirmed the benefits and disputed claims that the drug is harmful. (Aging, Oct 2019)
Epigenetics Is Crucial Salk Institute researchers have found epigenetic changes in experimental animals using chemicals or small molecules can rejuvenate cells and increased lifespan in humans. Assays based on epigenetic status promise to speed aging research by making it possible to evaluate therapies in weeks or months instead of decades.
Senolytic Agents Researchers have found drugs (Senolytic Agents) can eliminate old cells and dramatically slow the aging process, alleviating frailty, improving heart and blood vessels and extending lifespan. Middle-aged mice lived 35 percent longer than untreated peers and had less evidence of disease. Even mice dying of cancer lived longer than others. Phase I clinical trials have found the most-studied senolytic treatment, quercetin and dasatinib, safe for human use, though benefits will need much larger, longer tests.
Sirtuins may be ‘Fountain of Youth’ Molecules Researchers have found that a mixture of four molecules, similar to the proteins called sirtuins, reversed DNA damage and aging in mice. Researchers have identified a longevity gene (SIRT1) that can treat morbid lifestyle diseases and increase longevity.
Not all ‘Research’ Occurs in Formal Studies A growing number of amateurs, often with scientific training, are obtaining off-label prescriptions for metformin and rapamycin. Others are using senolytics and even GDF11 and Klotho, which are administered by injection in picogram doses. Many anecdotal reports suggest that all these therapies may offer clinical benefits.
Biotron Technology Jiang Kanzhen – a brilliant Russian scientist of Chinese origin – has been engaged in Biotron technology, the use of concentrated electromagnetic radiation of young organisms, such as sprouts, on old patients. Over 20 pilot experiments with old mice and old nematodes, all experiments received a positive result to extend active life. Old mice did not just live 25% longer, they were very active and died “on the run.” Even at the age of more than 100 years of human standards, they looked young.
Impacts and Implications
Data from 188 countries shows that life expectancy worldwide has jumped by more than 6 years since 1990, with many people living longer even in some of the poorest countries. However, extending the healthy period of life remains a challenge.
Growth of Geriatric Disease Longer lifespan may not be accompanied by extended “healthspan,” causing geriatric diseases to grow out of control. In the US, over 5 million people already are living with Alzheimer’s disease, and as many as 16 million are projected to have the disease in 2050.
Limited Medical Costs The growing frailty of old age is confined to a brief period at the end of life. Extending the healthy period of later life could reduce costs despite the growing number of old people. One study suggests that adding just 4.4 years to life expectancy, most of it in good health, could save US$7.1 trillion in economic value by 2060.
Extended Life Might Not Be Healthy Experiments with a tiny roundworm called C. elegans find that long-lived worms remained vigorous no longer than their short-lived brethren, then hung on in poor health. If life-extended humans followed this trend, geriatric diseases could grow out of control. However, roundworms are only one relatively primitive life form. Many studies in mammals have found that senile decay was compressed into a relatively brief period at the end of life.
Invitation to Contribute
Please look over the above analysis and send your estimates for the questions below to Halal@GWU.edu.
What is the probability that treatments for extending human life beyond 120 years are demonstrated within the following few decades? (Please specify probability from 0% to 100%. Or specify “Much later/Never”)
If this is likely, when do you think life extension will be demonstrated to be feasible and available commercially? That is, when the adoption level first exceeds zero: >0. (Specify the most likely year. For instance, 2045.)
Please estimate the average human life span when life extension technology matures. Think of reaching the “limits” of life extension. (Specify average total human life span in years. For instance, 250 years.)
Thanks for your help. Look for results in the next issue of TechCast Research along with the names of all contributors.