Human life expectancy over time has changed a lot. It has increased significantly over the years. Do you know what was the life expectancy of a cavemen ? If we go back to the Paleolithic era, to about 200,000 years ago , humans at that time , also known as cavemen , had roughly 25 years of lifespan . In the next millennia, nothing much changed .During the middle ages ,average age increased to 31 .
By the end of the Nineteenth century , due to the discovery of antibiotics and increase in easy availability of clean water , human lifespan extended to 40 . Childhood mortality rate radically improved. By the end of last millennium, average lifespan hit almost 76 . According to Worldmeters.info,the average life expectancy as of today is 73.2 years. Countries like Japan has a higher than average life expectancy, i.e. 85.03 , whether African countries like Nigeria has a lower expectancy of 55.75.
The main reason for which human life expectancy over time has increased is because of advancement in medicine. After industrial revolution, life expectancy increased significantly because of the discovery of antibiotics and increased availability of clean drinking water. Child morbidity also increased slowly after industrial revolution.
So, whatever the average life expectancy, we can confidently say that only a few people are lucky enough to live upto 100 years of age, even now. Wouldn’t it be awesome if we could extend life expectancy even further? Is it possible extending human life span even further than what we currently have? Is there any limit to how long can humans actually live? Can humans live for 1000 years?
Well,you will be amazed to know that a lot of cutting-edge research has been going on in this field, to increase human life expectancy in the future by reversing the process of aging. Many companies that are working in this field are trying to extend our life even further. In September 2013 , Google launched it’s new startup called Calico, also known as California Life Company .The aim of Calico is to combat aging and aging-related diseases and help humans in achieving longevity. Not only google but many Larry Ellison,the co-founder of Oracle Technologies, donated around $335 to ant-aging research . Billionaire investor Peter Thiel has also donated a lot of money in this research
Recently, I was going through news related to longevity research and I came to know that,in the field of anti-aging and human longevity research, scientists are working on mainly three approaches.
The first one is senolytic medicine, an emerging field of anti-aging medicine that targets “senescent cells”.Well, when cell division happens in our body, chromosomes inside the cell also replicate. By doing so, they lose a little bit of DNA. To protect the chromosomes from this, chromosomes have some long segments of DNA called telomeres . But they also shrink little by little after each cell division. So, after a number of such divisions, telomeres are just gone in some cells. These cells are called senescent cells.
For a long time, scientists didn’t pay much attention to senescent cells. They thought these cells don’t have any significance inside our bodies. Later we learnd that senescent cells create inflammation in our body and turn other healthy cells senescent, which ultimately leads to aging and finally death.
Senescent cells don’t die. The number of senescent cells increases as we grow older. These cells damage the tissues that are around them and are also the cause of many diseases such as diabetes, kidney failure, and other diseases related to old age.
In animal studies, it has been shown that destroying senescent cells could help prevent age-related diseases. Jeff Bezos-backed Unity Biotechnology is trying to develop senolytic medicines that target and destroy these senescent cells and restore proper function to previously inflamed tissues.
Young blood approach
The second approach in anti-aging research is the “young blood” approach. In 2014, Standford and Harvard University scientists did an experiment where they proved that blood infusion from young to old mice reversed cognitive decline in the old ones.
A startup called Elevian is working on a young blood factor called GDF 11. GDF 11 has been able to regenerate hearts , brains , muscles , lungs and kidneys in older mice when injected.
Stem cell therapy
The third approach in the field of anti-aging technology is stem cell research , which is showing the most potential . Now you might be thinking what stem cell is . Human body has different type of cells according to their function, such as brain cells, muscle cells etc.But stem cells don’t have any specific function but can be transformed to any other kind of specialised cells when needed later. One very rich course of stem cell is the human placenta .Placenta contains hematopoietic stem cells which is the type of stem cell that is being used therapeutically.
Samumed LLC, which is doing research in this field, is targeting the signaling pathways that regulate the self-renewal of adult stem cells, which, if successful would help heal tendons, regrow cartilage, remove wrinkles and also stop cancer.
Another company called Celularity, which was founded by stem cell pioneer Bob Hariri, is also doing research in this field. They have found that, in animals, placenta-derived stem cells can increase lifespan by 30 to 40 percent. They want to apply this to humans too, using stem-cell technology to increase the body’s ability to fight disease and heal itself and thus live longer. They also want to Celularity is also making stem cell injectables that will repair organs or tissues.
The future of humanity will be much different from today. Extending the human lifespan will not just be a dream for us in near future. Human life expectancy over time has only increased. It’s going to increase even faster than before because of the advancement of technology and medicine. We will live in a world of long-lived, AI-enhanced, globally interconnected human beings. If google’s engineer Ray Kurzweil’s prediction comes true, humans will achieve immortality by 2045.