What role does the sun play in your life? Well, of course life on Earth would be impossible without it, and our planet wouldn't even exist. Apart from acknowledging those simple facts, you may use the sun to tan, slap on sun screen to protect yourself from its harmful effects, or worry about skin cancer. You may even stay indoors during the really hot hours in summer, to minimize your exposure to dangerous UV rays.
While all those things are a pretty big deal, you probably never considered the possibility that the sun determines how fertile you are, how many children you will have, how many grandchildren you will have, and even how long you will live. Sounds like some kind of astrology? Actually, it's science.
Gine Roll Skjærvø headed a team of scientists from the Norwegian University of Science and Technology. They published their findings in the journal Proceedings of the Royal Society B. "The ultimate consequences of UVR on aquatic organisms in early life are well known, similar studies on terrestrial vertebrates, including humans, have remained limited," the research team wrote, and committed to change that.
How The Sun Affects Mortality And Fertility
They gathered data on people born between 1676 and 1878 in two different locations in mid-Norway by examining Church records. One of the communities was a coastal island population, while the other was inland. They otherwise had very similar climates and latitudes. A total of 9,062 lives went under the researchers' metaphorical microscope.
Here's where the solar activity aspect comes in — the solar cycle follows a very predictable pattern. Lasting a total of 11 years, it goes through eight years of solar minimum or low solar activity, followed by three years of solar maximum or high solar activity. The study team looked at meteorological data to determine the mean number of sunspots for the years they examined. Then, they divided the people whose records they obtain into "solar minimum" and "solar maximum" and went on to figure out how high levels of UVR early on in childhood affect the rest of people's lives.
Here are some of their fascinating and slightly eerie findings:
- People born during the solar maximum years lived an average of 5.2 years shorter than those who were born during solar minimum years.
- While infant mortality was generally a lot higher during the researched years than it is now (8.2 percent in the first year and 3.3 percent in the second for both groups), babies born during solar maximum years were less likely to survive.
- Girls born during solar maximum years went on to have a smaller average number of children, as well as fewer grandchildren.
- Poorer women were more affected by UV radiation than richer women, something that makes sense because they were the ones to work out in the fields, in the blazing sun.
A deficiency has a large impact on fetal formation in the earliest weeks of pregnancy, and therefore on general health later down the line. A lack of folate also reduces fertility.
Is This Still Relevant?
The years the research team examined are in the relatively distant past now, and the world has changed a lot since that time. This study might be interesting, but is it relevant to your life? Absolutely. Climate change and holes in the ozone layer mean UV rays will play an increasing role in our lives in the future.
Lead author Skjærvø says: "There are probably many factors that come into play, but we have measured a long-term effect over generations. The conclusion of our study is that you should not sunbathe if you are pregnant and want to have a lot of grandchildren."