Can the activity of the sun predict your lifespan?
Hi everyone, Crystal here for DNews.
Does the sun really have an influence on human lifespan and reproduction?
If the possibility sounds like some pseudo-scientific astrological nonsense, listen up, because
biologists in Norway are proposing that exposure to the sun rays can reduce your lifespan up
to 5 years, and if you’re female, make it less likely that you yourself will reproduce.
The study, published in Proceedings of the Royal Society B relied on historical data
found in records from 1676 and 1878 so we can be relatively sure that the people studied
spent most of their time localized to Norway and experienced the same solar conditions.
In a survey of the birth and death records of 8,662 people over the two hundred year
period the researchers chose to sample, the data showed a reduced life expectancy of up
to 5.2 years in people born during years of increased solar radiation.
And worse, women of the low socio-economic classes born during those times, were likely
to experience reduced fertility and low lifetime reproductive success.
So what does this mean? and why would the solar cycle, an ~ 11 year cycle of the sun’s
magnetic activity, have any influence on some human on earth’s ability to reproduce?
Well the answer may lie in UV radiation.
Of all the types of radiation emitted from the sun, it seems like UV radiation has the
worst reputation.
We know that UV radiation causes skin cancer and contributes to premature aging and DNA
damage.
But the authors of the Norwegian study attribute the deadly effects of UV rays to a molecular
mechanism.
Specifically, its destruction of folate.
Folate or Folic acid is a crucial biological molecule that helps out in many of the reactions
that keep our bodies going.
It is also necessary for cellular division because of its role in DNA synthesis and repair,
but exposure to UV radiation can destroy this crucial nutrient and have physiological consequences.
It is known that a deficiency in folate leads to complications in pregnancy and development,
but unfortunately for us, we can’t synthesize it ourselves, we’ve got to eat it.
Most pregnant women are encouraged to take folate supplements to promote proper fetal
development.
but its an easy bet that those Norwegians back in 1679 weren't able to pop a supplement
when they found out they were pregnant.
And today’s scientists think that low folate levels may be the reason for the low birth
rates and reduced life expectancy of people born during periods of high UV exposure.
Personally, I think it would be interesting to see if these results could be reproduced
in a modern population with access to sunscreen, and nutritional supplements.
And honestly, there are so many other variables that can influence lifespan and reproductive
success - like diet, and workload - in addition to environmental factors like the sun, that
at best this should be taken as a study of correlation, NOT causation.
But it is interesting to think about how phenomena we take for granted every day - like the sun
rising - may be having unknown consequences on the very paths of our lives.
What do you think?
Could the sun be influencing our life spans?
Subscribe to DNews and let us know in the comments down below.
Or find me on twitter @PolycrystalhD