Is there a citation for the following claim? I've never heard of such a thing:
"But then more results started coming back. Not only do astronauts come back with weak muscles and frail bones… But they also suffer from skin thinning, atherosclerosis (stiffer arteries), resistance to insulin and they suffer from loss of vision due to cataracts many years earlier than expected given their chronological age. These symptoms look a lot like skin aging, cardiovascular aging, age-related diabetes and so forth. In fact, it is pretty accurate to say that astronauts age at an accelerated rate."
Maybe it's attributed to the rigorousness of the selection process but I have noticed the longevity of so many astronauts.
John Glenn, Neil Armstrong, Buzz Aldrin, Michael Collins and Edgar Mitchell all lived beyond the average life expectancy of American males born when they were born.
Our bodies have incredibly complex feedback loops and we evolved here, with a constant 1G of gravity.
It's not surprising to me that exposure to Zero-G can have long lasting and unexpected consequences.
Cache since it appears to be dead: http://webcache.googleusercontent.com/search?q=cache:SYsBpU-...
Perhaps there needs to be more studies done on the effect of gravity and human health? Conversely, are there other things in our air (pollutants) that are in fact causing slower aging when on Earth?
On the reverse side, I've always wondered if being in a weightless environment makes your muscles feel great[0], since they aren't working against gravity. Over the years, gravity can create lots of problems for posture, which is why swimming (which lessen the effects of gravity) feels great.
[0] I'm using "Feel" in a relative context, since muscle weakness/wasting will not feel good once you're back in a non-weightless environment.
Sounds to me that its related to the "exercise" related to living in 1G. I wonder if the air mixture oxidizes the body more quickly as well.
They are also followed medically more closely than just about anyone on Earth: they don’t indulge in regular fast food
I wonder what they mean by that. Are astronauts explicitly banned from eating fast food, and somehow monitored? Or are they just less likely to eat fast food, since they pay close attention to their fitness and health?
I like the comment from petero:
Perhaps the effect is due to lack of grounding.
It seems strange aging also affects other things. http://www.japantimes.co.jp/news/2014/04/11/national/sakura-...
Maybe there's a diet-related problem? Astronaut food has some pretty intense constraints that Earth food doesn't, and has almost certainly been optimized according to the false discoveries of the field of nutrition. They should have a few people with different contrarian positions look over the food logs, and see if there's anything really wrong there.
This is interesting. You feel gravity less when you are in fluids. Does this mean all babies feel gravity differently because we all experience different amounts of fluid in the womb (not to mention the variations in baby sizes)? The impact is probably miniscule but I wonder if it has any effect on development of babies in the womb.
So the dawn of the 20th century radium spas are going to make a come back? https://en.wikipedia.org/wiki/History_of_radiation_therapy#J...
Microgravity is like alcohol; it effects so many systems in your body that it's really difficult to pin down exactly what is causing problems where.
I imagine this question won't be seriously answered until we have an artificial gravity system.
I love this sentence, cracks me up:
"They are also followed medically more closely than just about anyone on Earth: they don’t indulge in regular fast food."
One hypothesis: Solar and cosmic ionizing radiation ?
Certain bacteria in bodies die in space?
I'll repost the comment I made over there:
Have you guys heard about the entire field of study that is aerospace medicine? I’m taking a course on it this semester (I’m a masters student in aerospace engineering)–let me summarize some of the problems that your body goes through during space travel.
Humans spend about 70% of their time either standing or sitting. That means the human body is optimized for a hydrostatic pressure gradient like the one illustrated here (http://wiki.sdstate.edu/@api/deki/files/999/=1-BP_Change.png). Blood pressure is much higher at your feet than at your head. In space, however, there is no gravity to produce this gradient, so the cardiovascular system equalizes its pressure. That’s why astronauts suffer from “puffy face” (higher-than-usual fluid pressures in head) and “chicken legs” (lower-than-usual fluid pressures in legs). In their first couple days in space, astronauts lose about 1L of leg volume from each leg.
The CV system relies on internal pressure sensors to figure out how to operate, and the new pressure distribution confuses it. Astronauts lose a lot of blood plasma–it sort of ends up absorbed into the surrounding tissues. This increases the relative concentration of red blood cells, which triggers the body to slow down production of new ones. Also, the heart atrophies because it doesn’t need to pump as hard to move liquid around the body.
When you come back from space, your body needs to rapidly readapt from microgravity to one gee. It is not very good at doing that. That’s why 63% of astronauts are unable to stand for ten minutes straight just after their return from short-duration space missions (see video: https://www.youtube.com/watch?v=TPDST7EePXQ).
There are other problems: the cells that are constantly building and destroying your bones fall out of alignment when you’re in microgravity, causing astronauts’ bones to change structure in a way that looks a lot like accelerated aging. Why? Not clear, but possibly related to the lack of repeated loading, as happens when you stand/walk in normal gravity. Astronauts end up with huge concentrations of calcium in their blood, which causes kidney stones. Astronauts in space average around 4 hours of sleep per night, and very few of them eat enough calories to maintain their body weight, so they lose muscle mass.
Aerospace medicine is about half medical studies of astronauts and half studies of people on earth. It turns out that you can make most of these body changes happen by having people lie on their backs with the bed tilted down six degrees (head downward). Fascinating field. If you want to know more, I recommend the textbook “Space Physiology” by Jay Buckey (amazon link here: http://smile.amazon.com/Space-Physiology-Jay-C-Buckey/dp/019...).
I attended a talk [1] in which the made a case for the a British manned space programme as another angle on investigating ageing [2]. Radiation, boneloss, and a number of aspects. Ironically my memory of the talk is fading...
[1] http://www.bis-space.com/2014/03/04/12501/uk-space-life-and-...
[2] http://www.ukspacelabs.co.uk/about/5-strategy-r-d-themes