It’s been a few months of very little sunlight in the UK – incessant rain and grey skies when it isn’t raining – so on the few occasions when the sun has shone and I have not been at work I have spent as much time as possible outside. It feels like I have a physical craving for sun. Why sunlight really is a biological need is explained in the new book Chasing the Sun: The new science of sunlight and how it shapes our bodies and minds by Linda Geddes. It was a Christmas present from my best friend and I enjoyed reading it in the run up to New Year.

It turns out to be a book as much about the importance of sleep, body clocks and circadian rhythms as it is about sun, and it covers ground I enjoyed reading about in the other books on sleep (see my blogs on Why We Sleep and The Sleep Revolution). There’s a lot of history of ancient peoples’ relationship to the sun, how electric light developed and the effect it has had on our bodies and health, why shift work and jet leg are bad for us, and there’s an interesting perspective on the Amish community (see my blog on Reading the Amish) and their relationship to natural light.

For me, the most interesting chapters were those that were new to me. I was fascinated by how sunshine has been used in medicine as a cure for various ailments and how some enlightened (if you pardon the pun) modern hospitals are bringing this learning back into regimes for their patients. It also cites some alarming research about the impact of staying indoors at break time, either to avoid pollution or sunburn, on the eyesight of young children. Schools that make sure children go outside have seen reduced rates of myopia. There is also some really interesting research on ‘month of birth effects’ which suggests better health outcomes for children born at times of year when their mother was exposed to more sunlight during pregnancy. It also explores seasonal affective disorder (SAD) and encourages us to embrace winter – whether by cosying up in front of the fire with a good book, or by getting outside into natural light. My Christmas break certainly benefitted from doing both.