Modern humans like to think we are evolved, amazing specimens but really we are from an evolutionary perspective the same humans that we have always been. Our genetic code is the same as it has been for over 10,000 years and in those hunter-gatherer times we evolved with a strong circadian rhythm or a daily rhythm that follows a specific light dark cycle.
Our modern lives have not only disrupted this light-dark cycle but completely altered our circadian clocks with detrimental effects on our health. We have alarmingly high rates of obesity, diabetes, cardiovascular disease, cancer and much more which at least in part are due to our ancestral mismatch of our lifestyle with our evolutionary genes.
The mismatch is evident in many ways including but not limited to our lack of movement (sedentary lives), nutrient poor food, socially isolated lives, imbalance of work vs rest/leisure time, stressful jobs, internal pressure, lack of purpose as well as our disrupted circadian clocks.
Circadian clocks are the internal clock in our body telling us when to sleep, eat, grow, perform certain metabolic functions and when to clean up the body. Our clocks are influenced by light, sleep cycles, when we eat, when we exercise and when the clocks are out of sync we gain weight, create inflammation and have a propensity toward chronic disease states. By staying up late under bright lights, exercising at mismatched times and eating late we can high jack our clocks into thinking it is a different time of day. For example if you eat at 10pm your body thinks its daytime, ignites your metabolism, begins digesting the food and starts secreting hormones needed for when we are awake. All our hormones have natural circadian rhythms that when out of sync create havoc on our immune system, digestive system, brain health and much more.
So how do you live in sync with your old genes and circadian clocks?
- Light – get bright outdoor sunlight exposure in the first half of the day and preferably within 2 hours of waking to set the clock and for better sleep the following night. Remove bright blue light exposure in the second half of the day and specifically in the evening when we should be exposed to amber/orange lights. To do this you can change lights in your house to orange, add night shift and flux to devices and wear blue blocking sunglasses (see my recommendations below).
- Flux – free app for devices (https://justgetflux.com)
- Nightshift for apple
- True Dark – https://biohacked.com/product/truedarktwilight-var/
- Phillips Hue – (https://www2.meethue.com/en-gb)
- Exercise according to your circadian clocks and get daily movement. We want 3 types of exercise on a daily basis – lifestyle movement (we need to move more), cardiovascular exercise and strength exercise. Upon waking get out and move, go for a walk, do some cardiovascular exercise and move. Try the mobility routine below for an easy way to get your whole body moving. In the late afternoon before dinner 3/4pm try fitting in some strength training or high intensity exercise as this is when our muscles are most optimally primed for strength, growth and recovery. Also exercising not later than 4pm will allow your body time to recover before bedtime as late exercise can be a reason one does not get quality sleep.
- TRE or time restricted eating according to the circadian clock. Time restricted eating is simply eating in a window of time and not eating in the other window of time. Its recommended for overall health and reduction in mortality risk to eat in a window of 10 hours on average. This window should be the same every day if possible and the preference is to start early and end early rather than start late and end late. Not eating after 6pm can significantly alter health, promote better sleep, put one into ketosis or fat burning mode and modulate the immune system by allowing it time to rest recover overnight. At the very least pick a window and don’t eat within 2-3 hours of sleeping (all that late night snacking will keep you in fat STORAGE mode, alter sleep and stress the body when it is supposed to be in recovery, clean up mode).
- Rest – as modern humans we are so often working into the wee hours, stressing our brains and mentally exhausting ourselves which has far reaching detrimental effects on health as well as disruption of our circadian clocks. In the evening try doing activities that relax you, meditate, gentle mobility and generally wind down rather than work into the wee hours. Mentally our best time for creativity and tough mental tasks is the morning when we are most awake so try to set your difficult tasks for then
- Caffeine – caffeine has a half life of up to 6 hours so half of the caffeine can be still in your system 6 hours later. If you’re a slow metaboliser it can be longer and for some of the lucky few it can be much shorter but unless you have tested yourself genetically (23andme.com) you wont know so restrict caffeine to before 12pm on a daily basis to keep in line with your circadian clocks and to be able to sleep well that evening.
The Circadian Code by Dr Satchin Panda
Satchin Panda on Rhonda Patrick’s Found my Fitness
Satchin Panda on Dr Chatterjee’s Live Better Podcast