Why We Sleep by Matthew Walker, PhD

After hearing Dr. Matthew Walker interviewed on NPR, I immediately bought it and read it cover to cover – and enjoyed it every bit as much as the interview itself.  Dr. Walker has devoted his career for the past 20+ years to the science of sleep and has amassed a great deal of knowledge on the structure of sleep, the benefits of sleep, the medical and psychological consequences of a lack of sleep, and societal costs of our communal lack of sleep.

What is most impressive about this book is its readability – it is science-based but not full of jargon.  Dr. Walker describes each study that supports each of his claims about sleep, but he does so in a very clear and concise way so that any lay person reading the book can understand how the study group compares to the control group in each experiment and how the conclusions were made.  He also intersperses stories and anecdotes that engage the reader so that it is not just a preachy lecture but rather a mind-opening presentation of scientific ideas based on fascinating data.

His conclusions are many and of utmost importance.  Sleep is critical to our health and our ability to learn and retain memory.  Even getting less than 7 hours of sleep a night can have a detrimental effect on our health, increasing our risk of diabetes, heart disease, cancer, and infections.  It can have an affect on our memory and ability to learn – particularly in adolescents, whose school start times are early in the mornings (which doesn’t jive with their later circadian rhythms).  It can also increase risk of depression and anxiety – no wonder there is so much more of it now than there ever was before!

What causes us to sleep less?  We have electric lights that keep us awake longer into the evening/night.  We work earlier in the morning and then later into the night and then have activities and entertainment later into the evening/night.  We have electronic devices which have blue light/back lighting that send messages to our brains that inhibit melatonin that tells our brains that it is still daytime, so our brains don’t think it’s time to go to sleep yet.  All these contribute to later bedtimes.

So what to do?

I’ll suggest you read this book to find out.  There are great suggestions about sleep hygiene, treatment for insomnia (against medication, but supporting CBT), important lifestyle suggestions and some major public health recommendations.  The one suggestion emphasized the most?  To maintain a consistent sleep schedule throughout the week (including the weekend)!