How Does Daylight Affect Our Sleep?
When the clocks go forward to mark the beginning of British Summer Time, whilst tiredness on the following Sunday morning (plus the faff of having to change every clock in the house) may be forefront of our minds, but being deprived of an hour of sleep can also weigh heavy on our bodies too. Would you be surprised to learn that the Monday after the daylight-saving time change takes place, the risk of having a heart attack jumps up by 10 per cent according to scientists at the University of Alabama? In fact, the reverse happens when the clocks go back later on in the year. So what has light got to do with health? And what can we do to get on the right side of light?
Sophie’s dad, Brian Lamb, one of the UK’s leading medical herbalists, gave a talk recently on the subject of light and health; much of what is written here is taken from Brian’s, literally, illuminating talk.
Light And Health Are Inter-Related
We are beings of light: we consume light directly in the form of plants (which use photosynthesis – quite literally the processing of light – to live) and, indirectly, through the animals that eat the plants, but we also depend on light to live.
Light and health are inter-related. Our biological clock, the 24-hour body clock or circadian rhythm, is governed by light. Living under conditions of natural daylight, as we should, simplistically put this is how that 24 hour body clock runs: there is a surge in (melatonin-cancelling) cortisol at 4am that spikes us into wakefulness, peaking at 10 am in the morning after which it begins to decline reaching a low at 4pm. This is when, before the advent of artificial lighting, the red glow from a fire or sunset, coupled with a comforting meal would bring on drowsiness. The amino acid tryptophan from food produces the hormone serotonin which allows the pineal gland to secrete melatonin which brings drowsiness and the call to sleep. What we eat and when also plays an important part in regulating our internal clock; it lets our body know how long we have been active and how much of the day we have left. If we’re pushing past our natural slumps and sleep signals (yawning, feeling drowsy) and into our ‘second’ (third or even fourth) wind, this is effectively altering our body clock so we go to sleep later. Be a creature of habit if you want to sleep and be well, it would seem.
So what starts the body clock ticking? Morning light through the eyes. Light travels at speed into the eye and hits opsins in special photo receptors located in the iris which aren’t involved in seeing. A signal is then sent to the pineal gland and that starts the clock running, amongst other things, for release of hormones. All of our hormonal functions are set into motion by light and arguably the most healing of all those hormones is the hormone of darkness, melatonin.
In 2000 a book called Lights Out was released. Written by biochemist Dr Bent Formby and fellow researcher TS Willey from the Sansum Medical Research Institute at Santa Barbara, California, the site of cutting-edge diabetes research, the book explained for the first time how our hormones and serious diseases (cancer, diabetes, Alzheimer’s and mental disruption etc.) are intimately connected with light. In the same year, a study of 2000 Kaluli aborigines from Papua New Guinea revealed that only one marginal case of clinical depression was found. Why? Because the Kaluli lifestyle is very similar to our hunter-gatherer ancestors’ lifestyle that lasted for nearly 2 million years before agriculture and the use of light to prolong our day into the night.
Light (The Wrong Sort, At The Wrong Time) Can Also Be Bad For Health
Problem is, for the vast majority of us, we’re not living a natural life of rising with the sun and retiring to bed when the sunsets. Plus, for the first time in our history, we are looking directly at the mid-day sun all night/day long (via screens, tablets, smartphones, TVs, traffic and car lights, torches etc.) and we have never looked at the source of light before, much less during the hours of darkness. And it’s not doing us much good either. Fluorescent light, operating on the blue/green and UV light, spectrum is very bad for health; aside from irreversibly destroying retinal cells, it causes cataracts and disrupts melatonin (which is key for sleep) production. Operating at the polar opposite end of evening infrared and red-light spectrum (the light we get when looking at fires and candles) the bluish hue tricks the brain into suppressing the sleep-inducing hormone melatonin, and increases the energy-producing melanopsin.
Particularly destructive is light at night. One of the primary researchers on light is US neurosurgeon, Dr Jack Kruse who said that “…cancer is always tied to a disrupted circadian biology. Adequate circadian regulation of physiology and metabolism is key for metabolic health. When light uncouples these systems, cancer is right around the corner.” To prove his point, research conducted by Tulane University Circadian Cancer Biology Group, revealed that exposure to light at night, which shuts off night time production of melatonin, renders breast cancer completely resistant to tamoxifen. And more worryingly still, it only requires the tiniest amount of light to do that.
Make A Friend In Melatonin (Naturally)
On a more optimistic note, high melatonin at night puts breast cancer cells to sleep by turning off key growth mechanisms. We’ve known this for a while. Twenty years ago, Harvard University conducted an experiment where they took short-night mice, mice deprived of sleep, and long-night mice, that had a normal sleep in darkness, and injected both groups with carcinogens. The short-night mice died from cancer. But, and here’s the interesting part, all of the long-night mice didn’t develop cancer at all.
It looks like the greatest protection of cancer – all types – is sleeping in absolute darkness because darkness is pro-melatonin.
Melatonin is produced by the pineal gland. Located in the centre of the brain, the pineal gland is the size of a grain of rice and yet has one of the highest blood flows in the whole body which tells us it does a pretty important job. And so too, melatonin: it synchronizes the body clock, it’s a ubiquitous anti-oxidant and free-radical scavenger, it protects your DNA, it protects against radiation damage even from cell phones, it boosts immunity, it increases cell regeneration. Able to get into every cell and component of your body, this hormone of darkness is a powerful anti-cancer, anti-Alzheimer’s substance, provided you allow it to thrive.
What Suppresses Melatonin?
- Blue/green light from LED lights (as mentioned above that’s TV, smartphones, computer screens, tablets, lights etc.)
- Electromagnetic waves ie WIFI
- Adrenaline – so no arguments before bed!
- Insulin from a high carb meal in the evening
- Exercising (which raises adrenaline and cortisol) in the evening especially if exposed to blue light (better to exercise in the morning or the middle of the day)
- Eating late
- Drugs – beta-blockers, steroids, anti-depressants, anti-psychotic and any mind-specific drugs which wreck REM sleep
Should You Take Melatonin As A Supplement?
Well you can take melatonin as a supplement, but it’s much more preferable to obtain it for free by promoting good quality sleep in darkness (avoiding melatonin suppressants) and especially as a typical supplement is 1,000 x more powerful than the real thing. Plus, as Sophie, has already discussed in a previous blog, in isolating one compound are we missing out of the benefits of the other component parts? Does one compound truly function properly out of its natural environment? Possibly not especially when you consider that there are also co-factors which are secreted by the pineal gland alongside melatonin, substances that the medical world admits it knows nothing about. Bottom line: there’s no substitute for going-natural.
Resetting The Body Clock Naturally
So how can you reset the body clock? By spending more time outdoors. Researchers found that a weekend of camping outside (with no smartphones or LEDs) reset the body clock to be more in tune with nature’s light-and-dark cycle. The result was longer sleep and an internal clock in tune with nature’s. Saliva samples showed that levels of the “sleep hormone” melatonin started to rise around sunset, and the campers’ “biological night” kicked in about two hours earlier prompting campers to turn in much earlier than their usual midnight bedtime at home. They also woke up earlier, closer to sunrise.
In contrast, people who stayed at home showed the opposite pattern: on weekends, their biological night started even later than it typically did on a weekday.
The important point here is that you don’t need to go camping to reset your body clock, only to recognise that by behaving more naturally: by getting our more in the sun each day, minimising artificial light at night – using blue light blocking glasses too, embracing lights with a red/orange frequency in the evening by using halogen lights or incandescent bulbs and going to bed in a darkened room at the same time each night. Plus get outside as much as possible.
Get Up And Get Your Vitamin S (Sun)
Now if you work inside, getting outside sounds easier than it is in practice. So how much time do we absolutely need to spend outside each day? Well this also depends on the time of day and the best time of day to be outside, scientifically speaking, is the morning.
Exercising outdoors first thing in the morning boosts our body’s circadian rhythm as I explained above but there is also another reason to get out in the morning as Dr Kruse points out:
According to Dr Kruse both UV and infrared light are the most plentiful together in the morning (between 08:00 and 10:00) and infrared light helps enhance the absorption of UV rays in a healthy way too and, according to this study, people who were exposed to more blue light in the morning had an easier time getting to sleep (and getting better quality) compared to those who were exposed to periods of blue light later in the day.
An Hour A Day Keeps Illness At Bay
How long do we need to spend outside in the morning? It’s difficult to say, anywhere between 15 minutes and an hour possibly longer depending on your complexion. Every person is different. But for the average person of median skin complexion, 30 minutes to an hour in the sun without sunscreen will create adequate amounts of vitamin D. Morning exposure might have to be a little longer than this due to less sunlight intensity than midday. So my conclusion is, get out for an hour in the morning and if that’s not possible, Dr Kruse advises getting between 15-30 mins of sunlight between 11:00 and 13:00 which means for us desk-bound folk, reclaiming our lunch hours!
Overcoming The 1-Hour Daylight Saving Deficit
Well just as our exposure to the wrong light at the wrong times and ignoring our sleep signals, acting unnaturally in other words, affects our body clock, so does having to get up an hour earlier on the Monday when we haven’t quite adjusted to the new time. It’s literally a shock to the system which begs the question, why don’t we adjust the clocks over a Friday/Saturday night/morning to give us the weekend to adjust? Or why don’t we scrap the whole daylight-saving routine entirely?
Your greatest protection against cancer and dementia and for optimum sleep is the right light at the right time – blue light during daylight hours, red light in the evening and absolute darkness at night. Block out the blue light during the evening and at night using blue-light blocking glasses or simply switch off screens after sunset and read by halogen or incandescent light bulbs. Prioritise your sleep as much as you prioritise fitness/beauty/eating healthy regimes. Go to bed earlier in a dark as room as possible, wake earlier and spend an hour outside in the sunlight each day ideally in the morning or by reclaiming your lunch hour. Your health – and your sleep – depends on it.
PS. If you wake up at 3am this handy little trick helped us whilst we fixed our broken sleep.
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