Blue Blocking Lenses: The Science and My Results
I tracked my sleep using blue blocking lenses. As a doctor, I’m pretty skeptical of the whole biohacking world, but in the case of blue blocking lenses, I actually don’t see them as biohacking. What we’re experiencing in modern life is the biohacking. We are being hacked in a bad way with screens and blue light and a lot of the plights of modern life.
Why Sleep Quality Is the Foundation
Disrupting your sleep causes this cascade of negative consequences to your performance and to your health. Sleep is the driving force behind your mood, your cognition, your ability to gain muscle, to lose fat, to regulate your hormones, to manage your bone density, all these kind of things. And if you disrupt your circadian rhythm, it has an effect on almost every chronic disease: obesity, Alzheimer’s, insulin resistance, cardiovascular disease, depression, fatty liver syndrome. It’s multi-system.
From working night shifts, I know that it’s very easy to just reach for the donuts and the quality street because when you are sleep deprived, your feeding behavior changes. You become more hungry. You tend to actually crave more calorie dense foods. Your physical activity might go down. Your expenditure drops. All of that results in you getting fat and losing muscle.
The Problem: Modern Light Patterns
Throughout the day when the sun is moving through its pattern, it releases different wavelengths of light depending on where it is. When it’s at its peak, it releases the most blue light, which is involved in waking us up and stimulating a lot of our day cycles in terms of our hormones and our other processes. As the sun starts to set, it emits less stimulating blue light and more dampening red light to get us ready for bed.
The problem is that modern life is full of screens that just emit full spectrum light at us. And that causes our millions of years old brain to think that it’s always daylight. You can imagine what that’s going to do for your sleep quality and your sleep initiation. Getting the wrong signal at the wrong time knacks your sleep depth and your sleep initiation. This results in insomnia, not being able to get to sleep, and poorer quality sleep once you do get to sleep.
This is mostly regulated by photo receptors in the center of your retina that pick up differences in wavelengths of light. There are some in the skin as well, but mostly the eyes. Over millions of years, we’ve become really closely attuned to the rhythms of the sun. But recently, we’ve disrupted that and we’re feeling the consequences: insomnia, anxiety, depression, diabetes, sleep disturbance.
What Blue Blocking Lenses Actually Do
The idea behind blue blocking lenses is that they selectively filter out the big offenders, green and blue light on the spectrum so that we can return to that normal cycle. Some people including Andrew Huberman, smart guy, I respect him very much, would say that wearing blue blocking lenses is not natural. I would posit that everything else we’re doing is not natural and that what this is doing is trying to counteract that.
I have had patients complaining at 2 in the morning demanding a sleeping tablet. Meanwhile, they’re sat there with their phone on full brightness in their face and listening with headphones to some kind of house music. Like, what do you expect? I would agree with Huberman that you don’t want to wear these during the day because you do need some blue light exposure early in the day to start that clock ticking so that you can have a normal wakefulness cycle.
There has been a report published in the international journal of themology talking about other consequences of excess blue light such as dry eye, cataracts, macular degeneration, inhibiting melatonin secretion and increasing ACTH which is the precursor to stress hormones. So all of these are not things that we want day to day.
Modern life is full of screens that emit full spectrum light at us. That causes our millions of years old brain to think that it’s always daylight.
My Testing Protocol
I used a tool called Nomi, which is a nice simple web app that you use to log your data with. I can track my own data, but the science is the thing that should drive my decisions really. Subjective experience is very useful, but we need to look first at mechanisms, then at the data, and then at your own subjective experience. Otherwise, you can waste your time tracking everything under the sun and not taking advantage of the big leaps that science has made.
The other thing to say is that I was planning to do a much longer data capture, but at the end of the day, my data is rubbish. It’s patchy. There’s so many variables involved in tracking sleep. So much happens during a day and during a night that to say, “Oh, it was down to this one thing” – you can’t really until you look at larger scale trials.
My Subjective Results
The main things that I noticed subjectively were I was just sleepier before bed. And also once I put them on within 20 to 30 minutes I actually find the speed of my thoughts starts to slow down. My mind becomes quieter in the evenings and that’s huge for being able to lie in bed and your mind’s not racing.
Generally I think I’m just chronically a bit sleep deprived. So I don’t have any problems with sleep latency. I’m usually asleep within 8 or 10 minutes. But if sleep latency or sleep onset is something that you struggle with, then the data supports these helping.
The Shutdown Routine Advantage
The other thing I really like about them is that once you put them on, it’s like, okay, it’s sleep time, t-minus 2 hours. Cal Newport talks about having a shutdown routine at the end of the day, which is when you finish your work for the day, you get all of the remaining tasks that you’ve got to do tomorrow, you write them down, you close your emails, and you go, “Right, shutdown complete.” You close all the open loops for the day, close your laptop, you have a ritual that means that, right, laptop’s away. I’m now in home mode. And doing that just helps you to shut off a lot of those spinning open loops in your mind.
What the Research Shows
Improvements in sleep quality, sleep soundness, even mood, and an improvement in postpartum depression have been documented in studies. There’s a few more here that look at quality of sleep actually over time, which is interesting. Wearing the blue blocking lenses before bed for a single night might improve your sleep, but actually having a consistent routine of it seems to gradually improve things more and more over 3 weeks.
Blue blocking lenses seem to also be used therapeutically in some cases. We can see an improvement in mania in psychiatric patients and across multiple different measures in other surveys as well.
Why This Beats Taking a Melatonin Supplement
The thing that I particularly like about this is that it’s a non-pharmacological intervention. By wearing them, you produce more melatonin endogenously rather than supplementing with it and having introducing all the quality control and supplementation and absorption issues and cost and also potentially ruining your negative feedback process as well. Plus, it’s a bit more broadspectrum. Rather than taking a single hormone for sleep, this impacts your ACTH, your GABA, your melatonin, your 5HT, all these kind of things. And red light actually enhances some of these.
I’ve learned a lot looking into this, especially how the visual system is so tightly bound with how we process our emotions and how we sleep and our hormonal regulation and particularly the quality of thought and speed of thought. That was the big thing that I noticed. It’s worth looking into some of the recent science on how the visual system interacts with our brains, including EMDR research, the effect of walking outdoors, how different lights and colors affect us, and facial recognition response to certain types of imagery. It’s really fascinating stuff.
My mind becomes quieter in the evenings and that’s huge for being able to lie in bed and your mind’s not racing.
Common Questions
Do they need to be wraparound?
The cells in the retina called the intrinsic photosensitive ganglion cells have a blue sensitive pigment in the very center of the retina and so unless you’re looking directly at the light then the peripheral stuff shouldn’t really have an effect. So you don’t have to look like a speed dealer if you don’t want to. Obviously, there is a benefit. If you’re like training late at night and you’ve got this bright light everywhere, or if you’re doing shift work, particularly in hospital, for example, where it’s just blue light central, then the wraparound will be belt and braces for you.
Why not just wear sunglasses?
Sunglasses are just global darkening of everything. They don’t stop blue light. And so, if you’re trying to do stuff in the evening in a low light environment, you’re wearing sunglasses, you’re just going to be bumping into things. These still keep you functional. You can still see where you’re going. It’s just that they block out the blue light. So, it’s an important distinction that sunglasses are less functional and less specific to the benefit that you’re trying to get.
What about shift work?
The studies support that they do help people on permanent night shifts.
Why not block blue light all the time?
If you do that, you don’t get the wakefulness regulation. So you need blue light exposure during the day, but not in the evening.
My Recommendations
Honestly, I can’t knock these because they are a low-cost non-pharmacological safe intervention that you can use to improve your sleep quality forever. That’s absolutely priceless. There is a caveat though: you need to be careful which brand and which ones that you select because a lot of them if they’re cheap and they’re just tinted or have cellophane on top, they’re not going to block the blue light and then all you’ve got is you look like this but with no benefit. So, make sure that it does filter the peak wavelengths. And if the company doesn’t provide the specifications, that’s a red flag.
I would put them on 2 hours before bed. That’s where the data seems to get the most benefit from. And also include it with your bedtime routine. Don’t just see it as a plaster solution to something. You want to use the blue blocking lenses as a way to start the lead domino of the rest of your bedtime routine and get good healthy sleep habits.