DISCLAIMER: I originally wrote this article for my blog bueluk.com
I have spent the last 10 years working in high technology healthcare companies, building software that analyses data created by machines (from CT and PET scanners to DNA sequencers). To be fair, even if we could stop aging, living forever would still require the universe to exist forever and that’s not so clear (see this recent BBC article about the end of the universe – that’s a topic for another post). But what if we could live say, 200 years? Or perhaps 1,000 years? What about 10,000 years? Impossible? Maybe not.
From a life expectancy of 35 to 80 years – and where this is going
Take a look at this graph (data courtesy of Office for National Statistics):
During the last 200 years, we saw the average lifespan of human beings going from about 40 years in the mid 1800s to about 80 years in the developed world today. There is still work to be done in many countries that don’t enjoy the same level of healthcare, safety and hygiene as developed countries, but we should eventually get to a point where this is available universally.All of this improvement has been achieved by preventing and curing diseases and a general improvement in the levels of safety (for example in transportation – cars are much safer today than they were in 1950, laws and policing reduced death from violence). But even in developed countries, most people still don’t reach 120 years.Why?Because we still have diseases such as Cancer, Alzheimer’s and Heart Disease. According the WHO, these are some of the 3 top killers in the USA along with Influenza, Diabetes, Chronic Respiratory Disease (seehttp://www.medicalnewstoday.com/articles/282929.php).So if we are to live even longer, perhaps even past 122 years which is what’s currently thought of as being the maximum life span of human beings (seehttps://en.wikipedia.org/wiki/Maximum_life_span) the following needs to happen:
STEP 1: Curing all diseases
I believe that we will get to a point where all diseases are curable. Normally, when I say this, people laugh. Do you have any doubts that all diseases will one day be curable?Look at infectious diseases. The biggest killer in the early 1800s was tuberculosis (seehttp://www.thornber.net/medicine/html/causesofdeath1839.html). How is TB nowadays? Pretty manageable. I know, I know, there are concerns around antibiotic resistance, but this is problem that will be solved. The point is that during the last century, modern medicine managed these diseases.What about cancer? In the 1950s only 35% of cancer patients survived 5 years after diagnosis. In the early 2000s this number was around 67% (see this study). Nowadays, it’s even better. Do you see the trend? And with the latest advances in genetics and genomics, the future looks promising, and I expect that not long in the future, cancer will become a manageable disease, just like tuberculosis.Remember, while infectious diseases are caused by mutating infectious organisms, which means that they are always evolving and the mutations acquired by one set of individuals can be used again when they infect a new host, in cancer this doesn’t happen. If you have a group of people infected with HIV at a given time, that’s billions of viruses going through trial and error mutations trying to evolve and trying to find ways to avoid our drugs while in cancer, a limited number of cells in an individual have a chance of evolving and once the individual dies the cells die too and cannot pass any evolutionary tricks to a new individual. So in a sense, once we dominate cancer, that’s it – it’s dominated.
STEP 2: Replacing aging organs
I am not sure if this will really come after STEP 1 above or if there will be some overlap. Probably the latter.If we want to live longer, simply curing all diseases is not enough. The problem, is that most of the increase in lifespan we got in the last couple of hundred years has been achieved by simply eliminating the reasons why people die prematurely. We cured diseases, and we got very good in preventing them. But despite all this, no one ever lives past about 122 years. This is because it seems that 122 years is the absolute maximum lifespan of a human being (see again https://en.wikipedia.org/wiki/Maximum_life_span)Once you get too old, there is so much damage in your DNA that your cells won’t replicate anymore and a range of issues arise in your body. For example, your heart won’t pump like before, your lungs start to collapse, your immune system isn’t as effective, your kidneys start to fail.So one nice prospect is being able to replace old organs with new ones. You could get a new heart every 50 years or so, made out of your own cells. When you reach 100 years of age, you would have a young person’s heart again.When I talk about new organs, I also mean blood and skin. You should be able to receive new skin and look like you are 25 when you are 75. Recent research has shown that receiving young blood may make your body operate like new again (at least the brain, for now:https://www.ucsf.edu/news/2014/01/122211/blood-work-scientists-uncover-surprising-new-tools-rejuvenate-brain).Young blood making you younger is great and it means that there must be something in the plasma that we don’t yet know/understand that is having this effect, but what I find really interesting is thinking about the possibilities of stem cells. The promise with stem cells is that you can take a cell from your own body and convert it into something called a pluripotent cell which can then be made to reproduce and build entire new organs.While these approaches wouldn’t necessarily make us live way past 122 years since we are basically just replacing old organs with new ones, it would certainly make us live a much better life in old age, and this is already a huge benefit for the human race. A good life always, as it should be.If you want to know more about stem cell, there is good information in this NIH website.
STEP 3: Molecular modifications
Now this is the possibility that I find most exciting of all. Imagine being able to have your DNA edited, so to programatically increase your lifespan. I say programatically because this is what DNA is – the set of instruction code that tell our cells how to behave. Pretty much like a computer code tells the computer how to behave.
The latest editing techniques known as CRISPR promises to allow easy and precise genetic editing. It’s like a molecular scalpel that cuts our DNA in a precise location to change the code.The most accepted theories today stipulate that aging is the accumulation of damage to cells – and more specifically DNA – which eventually leads to the cell being unable to reproduce and even committing suicide in a process called apoptosis. So it may be possible to edit the DNA in such way to either tell cells to reproduce more times before ending their life-cycle or altering the way that they deal with their death.Think about it this way: A mother in her 30’s who only have a lifespan of 92 years left in the best case scenario can give birth to a new human being who has a brand new lifespan of 120 years. The cells of the baby are created inside the mother’s body. So surely, there is a way for a 30 year old body to produce cells with normal lifespan, which means that there must be a mechanism that determines what a cell’s lifespan is, and we just need to understand what that is.
Social implications of longer lifespans
One of the first things people mention in a discussion about life extension is the fact that we will run out of resources and space on earth to deal with so many people.
Ray Kurzweil is a futurist who’s work I have been following for a while, mostly due to his software engineering skills rather than his futurology work. He published a series of books and defends the idea of a “singularity” which is when computers will be as smart as human beings and humans will be able to upload their brains to computers and live in virtual reality worlds. He makes bold predictions about the dates when things will happen (you can check them out here).According to him, we would be able to edit genes and rejuvenate our body’s skin by altering the DNA still in the 2010s and in the 2020s we would see the nanotechnology revolution with the use of nanobots in medicine and all sorts of ways. Now, I think that Ray is a super smart guy but his predictions seem to strangely rely too much on Moore’s law (which has worked well for the past few decades but is showing signs of breaking these days) and his own desire of living forever, so many of the dates he sets seem to gravitate around his own lifespan.I don’t think anyone can make accurate predictions about when exactly the steps above are going to happen. One thing I learned in all my years working with healthcare and pharma companies is that things in healthcare take longer than you think.Irrespective of what you think about Ray, there is one point he makes that I fully agree: that the same technological advances that will enable us to live longer, will also solve other problems along the way in terms of natural resources and space. Many things come to my mind, from using solar energy instead of oil (and therefore much cleaner) to desalinizing water (since we have cheap and clean electricity) to creating colonies in space stations, the moon, mars and other planets.It is up to us to make sure that this technological advances go in the direction that we want – in a direction that will improve the standards of living of people and at the same time making us more human (and here’s another point I disagree from Ray since he thinks we will all become machines). Allowing us to live life to its fullest, enjoying all the sensations and emotions that make us who we are. This will not happen by default, we need to keep an eye on the companies that are developing these technologies and demand that our governments act as to ensure that technologies are used for the good of humankind.