The urban legends disseminated over decades have fed a mythology around the human body that can lead to misunderstandings. What’s more, fiction has contributed to expanding these myths and to anchoring them in the collective imaginary. We have assembled some of these stereotypes in an attempt to explain how much is true and how much merely fantasy.
1 – Space travel affects the human body
We may very soon be seeing the first tourist trips into space, so one evident concern is how this kind of travel can affect people who travel beyond the Earth’s atmosphere once they return to our planet. Apart from growing as much as 5 cm as the vertebrae move apart in the absence of gravity (although they return to their original state), space agencies are studying what other consequences it would have for our organism.
To this end, NASA launched the Twins program, in which it sent a subject into space while his twin brother remained on Earth, so they could subsequently be compared. The lack of gravity alters our genetic composition and causes physiological problems such as muscle atrophy, loss of vision and bone mass deterioration, as well as other potential problems like space radiation. To find out more, read the full article in How does space affect the human body?
2 – Why do we tan?
Skin color changes when our bodies are exposed to the sun, but a tan was not always synonymous with beauty and health. For centuries, white skin was a symbol of belonging to high society, as kings and nobles were not exposed to sunlight. It was only in the early 20th century that –almost by accident– a famous designer made intentional tanning fashionable.
However, a tan is not so common in all cultures, as it depends to a large degree on social perception, and numerous myths have always surrounded the process of sunbathing. You can learn more in Why do we tan?
3 – Can the human body be cryogenically frozen and brought back to life at a later date?
In spite of the urban legend, the body of the famous animation artist Walt Disney has not been cryogenically preserved until a cure for his cancer is found. The celebrated creator of an audiovisual empire was cremated two days after his death. This false story has fed the idea that it is possible to cryogenically freeze humans in order to return them to life when scientific advances allow.
For the time being this (expensive) process belongs more to the realm of fiction, as human cells cannot be brought back to life after having been frozen, although there are experiments underway with other living beings. If you want to find out more about this controversial treatment, take a look at the article The dream of cryopreservation.
4 – What colors can colorblind people not distinguish?
Color blindness has always been a subject of interest and research, and has also attracted its fair share of myths, most of which revolve around the colors that colorblind people can distinguish or tend to “confuse”. The first person to investigate the pathology (and give it a name) was the English physicist John Dalton, who himself suffered from this genetic alteration.
Thanks to Dalton’s pioneering work we can today distinguish between the different types of colorblindness according to the chromatic range and the distortion experienced when perceiving it. You can learn more about this story in The colorblind scientist who envisioned atoms and Which colors to people with color blindness confuse?
5 – Can sleep be recovered?
The activities we carry out in our daily lives configure what are known as circadian cycles, which –when altered– can destabilize our organism and produce fatigue, disorientation or insomnia. This effect is known as jet lag when the effects occur due to a sudden change in the time zone.
It is estimated that we humans should sleep an average of eight hours a day. If we do not do so for several days in a row, our exhaustion will increase and we will accumulate a “sleep deficit”. Unfortunately, it will not be enough simply to have a longer lie-in at the weekend; to cancel out our “debt” we will need to increase our daily amount of sleep as close as possible to 8 hours. This way our body will automatically adjust itself to the rest it needs. If you want to know more about circadian cycles, you can do so in the article Thousands of biological clocks keep time in the human body.