Russell Foster was a professor of neuroscience at Oxford and the director of the Nuffield laboratory of eye care. The Zoological Society medal was one of the awards he received for his discovery. His newest book is called Life Time: The New Science of the Body Clock and How It Can Revolutionize Your Sleep and Health.
There is a fundamental understanding of how our biology works. Understanding how different structures interact within the brain is bigger than that. That is included in our entire biology.
Over the past 25 years, there has been a move into understanding how these internal 24-hour oscillations are generated and I think it is an amazing success story in biomedicine. The suprachiasmatic nucleus, with 50,000 cells, is one of the parts of the brain that has different functions. All of our rhythms are gone if you don't have that.
It was mostly through the eyes of the photoreceptors. During my second year as an undergrad at Bristol, I came across a book about lampreys by JZ Young. mammals don't have a parietal third eye, but fish, reptiles, birds and other animals do. I just thought that this is really cool. I was trying to understand how light is used to regulate the seasonal biology of birds. I began to address the question of how the clock of mammals is regulated. We have visual cells that grab light in a fraction of a second and then forget it. How can dawn-dusk detectors be used to collect light information over a long period of time? In the early 1990s, we suggested that there was an undiscovered photoreceptor in the eye.
I wanted to kick back against the sergeant majors of sleep screaming: ‘You can’t look at a Kindle before bed’
You weren't well received by your peers. We kicked the door until they paid attention to us. You can draw parallels from studying different evolutionary responses to the same problems in zoology. It wasn't so big of a leap for me to say "Maybe there's another photoreceptor within the mammal eye."
The book was written because of the amazing developments in sleep and circadian research that are important to health across the spectrum. The sergeant majors of sleep screamed: "You must get eight hours" and "You can't look at a Kindle before you go to bed". One size doesn't fit all when it comes to sleep. It's an amazing part of our biology. In public talks, a man came up to me and asked if he was going to die. You are going to die, but not necessarily because you don't get enough sleep. We have generated a lot of anxiety as a result of this, so I want to take some of that away.
The modern world has changed the way we clock. It has been said that cheap electric light has had a big impact on the development of human societies. It has been democratising, but we still take things too far. We are not free by our biology. You have the option of nudging it one way or the other, but you have to respect it.
99% of shift workers don't adapt to the problems associated with night-shift work. What are the repercussions of that? High levels of coronary heart disease, cancer, immune suppression, metabolism syndrome, and type 2 diabetes are more prevalent because we are pushing our biology outside its normal range. We don't need to put the society back in its bottle. It is here to stay, but we have to be aware of how we can mitigate it and employers should develop more of a duty of care attitude.
Is there such a thing as larks and owls? Some of the clock genes have a genetic tendency to speed the clock or slow it down. It's more than that. There is a tendency to want to go to bed later and later as you get older. Men peak at 21 and women at 19 and a half. We tend to get up earlier as we get older. We are getting up and going to bed the same times we were when we were 10.
When you see light, it's also to do with it. Morning light advances the clock while dusk light delays it. If you are struggling in the morning, you can sit in front of a light box or go outside and get some exercise. Even if you are an owl, you can shift in the right direction.
Getting morning light into your eyes is one of the most important things to do. If you are a real lark, you make sure you get evening light.
A few years ago, a nice study was done comparing athletic performance in early, mid and late types, and as you might guess, the morning types peaked at noon, the intermediate types at 3pm or 4pm and the late types at 4:30pm. If you only want power and peak performance, then it will correlate nicely with your chronotype. If you want to do something, it's up to you. Exercise before breakfast to burn calories. Do it later in the day if you want to be more energetic for longer. It's a good idea to not exercise too close to sleep. A small loss in core body temperature could be caused by that.
The timing of our meals is an issue. Dinner in the evening is a terrible idea. He said to eat like a king in the morning, a prince in the afternoon and a peasant at dinner. If you don't exercise late in the day, your metabolism won't be able to burn calories in the first part of the day and you'll end up with more fat than calories. People lost more weight when they ate earlier. We think of the great Tudor banquets at night, but it's lunchtime. The aristocracy said: "We're liberated from the loss of light" that eventually led to eating. It was a display of wealth that spread across society.
Your ability to drive your car in the early hours of the morning is worse in terms of cognition than if you were legally drunk
It's important to tell me about chronopharmacology. The future of medicine is going to be influenced by this, as over 100 drugs have different time-of- day effects. Kids with a severe form of leukaemia were treated in the morning or early evening in 1993. 70% of the people were still alive after the evening treatment, compared to 34% on the morning treatment. A five-year study shows that ovarian cancer survival is around 45% on one day, 10% on another.
The decision-making skills can vary depending on the time of day. The level of cognitive impairment was compared with the level of alcohol consumption. The level of impairment was higher at night. The ability to drive in the early hours of the morning is worse than if you were drunk.
I don't know what our education system has done. The first thing in the morning is all the demanding subjects. The kids bounce off the walls in the afternoon while they sleep during the critical mornings. We might think it's a good idea to move some of the demanding classes to the afternoon and have sport in the morning.
It is difficult to say from the female side, but from the male side, sperm quality is better in the morning than in the evening. The person who heard me on the radio sent me the most amazing email. We have been trying to have a child for the past two years. We had forgotten about the rhythms of the day. It worked the first time we did it. That is a great responsibility.
We should be looking at the sun instead of the clock.
Stress and anxiety are the enemies of sleep, so at the end of the day you have to find ways of de-stressing. I thought that it was a bit like crystal-waving. It's not. It's clear that it helps you take possession and de- stress.
Getting morning light to set the clock is something we have discussed. Making the bedroom a haven for sleep is one thing. It depends on one's individual economic circumstances, because the bedroom is often the office, particularly during lock down, but ideally, get rid of all that stuff and invest in a decent mattress and pillows.
I have found that writing this book helped me define when I am best at my job. One of the joys of being a full professor is that you can decide when the meetings start. Eating times have changed a lot. I do a short 10 minute session before breakfast and then do a longer bout of exercise later in the day.
Russell Foster wrote Life Time: The New Science of the Body Clock and How it Can Revolutionize Your Sleep and Health. Go to guardianbookshop.com to order your copy. Delivery charges can be applied.
All Rights Reserved © 2024
