Science is fun, especially these days, when it sounds more like science fiction than science. But before we get into the fun stuff, let's remember what we really mean when we talk about aging.
For most of human history, the average lifespan was between 20 and 25 years. This wasn't because 25-year-olds suddenly keeled over--it was because 20% of children died in the first 5 years of life, because motherhood was almost as fatal as childhood, and because witch doctors and shamans didn't have as much luck with their charms as our doctors do with penicillin. Murder and warfare, contrary to our romanticized view of the past, were actually more common than they are today, as was famine. This lowered the average for the entire population. But, if you made it over each of these hurdles, you stood a chance at reaching the Biblical 'three score and ten,' and many did. But not enough to pull the average lifespan up to a respectable figure, such as the 88 years that Japanese women can expect today.
The fact is, even if we don't extend our lifespan at all, our lives are immeasurably richer than before, as we don't have to live in as much fear as did people just 200 years ago. (If we choose to live in fear, so much the worse for us.) But as we knock down the old hurdles that kept so many of us from reaching our allotted timespan, new ones crop up, such as Alzheimer's disease.
Now that science has done so much to bring the average lifespan up by eliminating the premature causes of death, we are turning our attention to the latter stage problems such as cancer, dementia, COPD, etc. The question is, will we have as much success fighting these conditions as we have had fighting infectious disease, childhood and maternal mortality and the like.
Take nanotechnology, which is making tools and products, and providing services, with very small things. Very small. About one billionth of a meter small. We're doing it now--there are more than 1,500 products licensed for consumer use that use nanotechnology today, although most of them are things like sunscreen and other coating materials.
I sometimes make predictions for a living, doing something called PESTLE and SWOT analyses. Here's a prediction for you: Nanotechnology will do for this century what electricity did for the 20th Century--change it so radically from the previous century that the lives of those coming before will be almost unrecognisable.
Nanotechnology will hold some, maybe many, of the keys to our battle against aging. This article from back in the Stone Age (2002) gives some clues about the goals:
"Fifty years from now, what causes of death will be preventable? That depends largely on the technology we will have available, so let's start by projecting some technology trends. Gene sequencing and identification will be as easy as a blood sugar test. Medical devices such as artificial hearts and insulin pumps will be implantable and well-integrated with the body's natural demands. Surgical instruments will be more delicate and less destructive; what today is "major surgery" will be done with an office visit. Computers will be millions of times faster than today's machines. Last but not least, we will probably have the ability to build strong, useful, complex machines out of individual atoms and molecules. This is called "nanotechnology" or simply "nanotech", and it will make us healthier in several important ways."
"Can we expect technology to solve all our medical problems? This chapter will answer that question by examining what nanotech can do for medicine. Nanotech is a huge topic, and medicine is even bigger, so this chapter can give only a sketchy overview. On the nanotech side, we will focus on robot-like machines with precise molecular parts; on the medicine side, we will limit ourselves to a mechanical view of medicine that mostly ignores the complexity that arises from all the body's systems working together. And I'll be remarkably unambitious (by future standards) in defining "good health": Good health is when the body is able to support typical activities without significant discomfort. (Optimum health is a matter of personal preference, and the chapter is long enough without getting into all the ways people could improve their bodies.) Even with these restrictions, it will become clear that nanotech can solve most or all of the medical problems that might keep us from being in good health, thus allowing us to remain in a state of good health for many decades or even centuries."
..."Medical theory and technique today are a vast improvement over the state of the art a century ago. However, by comparison with what could be, medical practice today can only be described as primitive. Surgery creates huge wounds which require days to heal. Cancer therapy usually aims to be as destructive as possible, without wiping out anything too important. Most of our drugs were discovered by trial and error, and their side effects are sometimes drastic. Organ transplantation requires crippling the immune system. Many conditions cannot be cured at all. The good news is that even basic nanotechnology can correct most if not all of these problems."
..."A problem can't be corrected unless it is first detected. One of the first contributions nanotech will make to medicine is in the area of research. Miniaturization will create probes that gather orders of magnitude more data. Chemical sensors can be built small enough to put inside living cells. Probes may be thin enough to go through tissue without causing noticeable injury. Small, low-power devices may be implanted for continuous monitoring."
..."The normal way to deliver a chemical today is to dump it into either the bloodstream or the stomach, and let it spread all through the body. For some chemicals, such as insulin, this is appropriate. But for others, such as chemotherapy drugs and some antibiotics, it is best to keep them as local as possible. Nanosurgical techniques can put drug delivery devices right where they are needed. The devices can be numerous and tiny, so that they can be inserted into any organ. In most cases, the devices could manufacture the required chemicals on the spot, using elements and energy from the surrounding tissue, thus eliminating the need for holding tanks and external supply. (Nature has demonstrated that a complex chemical factory can fit into the space of a bacterium.)"
..."If an organ fails, we must either replace it or do without. Usually the replacement organ comes from someone else, which means that the body will reject it unless drugs are taken to cripple the immune system. Today several organs, including the larynx and the bladder, have been grown on special scaffolding. With nanotech to build far more complex and precise scaffolding, we will be able to create most organs this way from the patient's own cells, thus allowing rejection-free transplantation.
Artificial organs will become far more feasible. Today, artificial hearts have been used in a few cases, and the use of external artificial kidneys (dialysis) is common. These devices don't work very well, though they are certainly better than nothing. However, a nanotech-built device could use the body's own energy supply--glucose and oxygen--for power, and could be far more sensitive and responsive to the body's condition."
Sounds like science fiction, right? But in the 7 years since this article was published, scientists have been working on each of these areas (and more). In our next nano post we'll look at what's being accomplished.