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Today, we are constantly exposed to artificial light that contains blue light that impacts our sleep, circadian rhythms, and hormone production. Ages ago our last daily exposure to blue light came with the sunset. After dark, the light we were exposed to was mainly from campfires that contain mostly red light. There is a lot of evidence on how blue light can affect fertility in both men and women, how it can affect your sleep, your hormone production during pregnancy, and even your breastmilk and your baby’s circadian rhythms. This episode features Andy Mant, who is well versed in the evidence and research on blue light exposure. Learn about the risks of blue light exposure and how to easily clean up your light hygiene. Plus, why apps like night shift and Flux do not do enough to protect you. This episode gives you simple hacks you can do to reduce your blue light exposure after dark, reset your circadian clock, protect your baby’s circadian rhythms, and stack the odds in your favor for fertility.

There is a fantastic article written by Andy Mant that includes links to all of the research studies we discuss.


Vanessa: Today on the Pregnancy Podcast I have Andy Mant who is the founder of BLUblox, which is a company that makes blue light blocking glasses. The reason that I brought Andy on the podcast is that he is a pro with all of the research behind blue light and how that can affect everything from your hormones, how it can impact your fertility and even how blue light can affect your breastmilk. Andy, thank you so much for joining me on the podcast today.

Andy: Thanks Vanessa, it is an absolute pleasure and thank you so much for having me on our amazing show.

Vanessa: It certainly makes my job easier to have someone on who has dug into all of this research. You have shared those studies with me and I spent quite a bit of time reading through those studies you shared on blue light and I am really excited to talk to you about all of this stuff today.

Andy: Absolutely. I’m super stoked with how much time you took to actually read. It just really shows that you take these things seriously and you really want to see, how does the evidence stack up and do your guests actually know what they’re talking about. So I’ve really, really liked that. Your audience can have that rest assured feeling that you’ve done a lot of due diligence on this as well. And yeah, it’s going to be a fun chat.

Vanessa: Definitely. Thank you. I’m excited to share a lot of different tips that everyone can take away with to limit some of the blue light that we’re exposed to. Can we start by talking about sources of blue light and get into a general conversation about how that can affect you?

Andy: Absolutely. There are two different sources of blue light in our lives. You’ve got artificial and you’ve got natural. Natural light is what comes from the sun during the day. It is high in basically all different colors of lights, blue, green, yellow, orange, red. Think of a rainbow. That’s all the different colors that are present in sunlight. They are all very even and they all have very different properties in what they do to hormones. For instance, blue light during the day from the sun is very good because it releases something called dopamine, which makes us feel good. It’s the reward center in the brain. It also helps us produce serotonin, which is really good for making us feel happy and alert. Also, it helps increase something called cortisol which is good during the day and that jumpstart helps you start your day.

Now in natural light like sunlight, because all the colors are balanced, there’s a lot of red light present. Any of the damage that blue light causes from the sun, which is it does cause damage, it causes cellular damage. So you can get like inflammation in the skin, you can get problems with eye strain, things like that. Blue light causes cell damage, the red light and the sun actually protects and restores. Nature is very good at giving us the benefits. But if there are any negatives, it will always help to heal and repair. Now on the flip side, you’ve got artificial lights. Artificial light comes from sources such as your smartphone, your laptop, your monitor, appliances, your fridge light, your office lights, your house light, your TV, anything really that that gives out or is powered by artificial light typically is very high in blue light.

Now the difference between artificial light and natural light from the sun is the artificial light doesn’t contain any red light. You get all the benefits of the blue light if you’re looking at your computers and laptops and things like that, but you’re not getting any of repair. The blue light is causing damage from your smartphone, your screens, etcetera. It’s causing things like digital eye strain during the day, headaches, dry eyes because you’re not mitigating those effects with red lights. Also in artificial light, the blue light present is so much more than what’s present in sunlight. So you’re getting almost an overdose type effect with blue light, which is causing a lot of digital eye strain.

On the flip side, when it comes to blue lights after dark, when we think about it from an ancestral point of view and into the modern-day, we all have something called body clocks. People probably would’ve heard of these, they are sometimes called circadian rhythms. What they do is they allow for specific hormone secretion based on different frequencies of light. From an ancestral point of view, we would have got up with the sunrise, we would’ve been outside all day exposing ourselves to all the different frequencies of light hormones, which are secreted correctly. And then when the sunset, there was only really red light and orange light present from the campfires, there was no blue and green light. What recent studies have shown is that blue light turns on the circadian clock. It turns on our body clock and allows for hormones to be secreted that keep us active during the day. But what happens in modern society is we’ve moved away from incandescent lights to led lights, which are high in blue light. So when we’re switching on our lights, watching TV, scrolling for our smartphone after sunset, the blue light is present in those devices is sending messages to our brain to be in an active phase. It thinks it’s daytime, so we don’t produce a lot of the hormone called melatonin, which is a powerful antioxidant and sleep hormone which disrupts our sleep, doesn’t help cure inflammation and damage that are caused during the day and is really just destroying our sleep and giving us really low energy levels.

Vanessa: It is such a huge shift that we’ve made. I love looking at things from an ancestral point of view and thinking about how all of this technology that we have is amazing with phones and laptops, but our exposure to this has happened much more quickly than we can develop mechanisms to mitigate the dangers. Certainly, when you’re pregnant, your hormones rule completely everything that’s going on in your body. Can you talk about some of the effects on different hormones that happen, not just obviously in melatonin and has a huge impact on your sleep, but some of those other hormones like estrogen and prolactin?

Andy: Yeah, absolutely, not a problem at all. What I mentioned earlier is melatonin the key to all this. A lot of people think melatonin is just sleep. Melatonin sort of peaks around about two or three in the morning. Its main responsibility in the human biological system is to clear inflammation and oxidative stress. It clears things like reactive oxygen species which caused damage to sales in the body. Melatonin can actually only be produced in the absence of blue light. During the day, there are some precursors to melatonin. You produce things like serotonin from being outside and you also produce something called tryptophan from things you eat. It is these two hormones and neurotransmitters that mix in the absence of blue light to produce melatonin.

You can see that it’s very important to obviously be outside during the day to create these precursors to melatonin. It’s also extremely important in order to be able to optimize the production of melatonin, not to have your eyes see any blue or green lights after dark. If you’ve got any artificial light source on in your house after dark, then you’re not going to be producing enough melatonin. We need melatonin to cure the inflammation and keep us healthy, keep us fit. All hormones are controlled by circadian rhythms and our biological clocks, and estrogen is one of those. Estrogen plays a really big role in the reproductive systems of women.

What studies have seen is the estrogen has been known to modify clock genes in the reproductive system. What that means is that if your estrogen cycles are either too high or too low, or they’re running basically against what our ancestral circadian rhythms determine is optimal, then the clock genes in the reproductive system will be impaired. What that leads to from what a lot of the peer-reviewed studies are saying is it can increase the likelihood of developing things like PCOS (Polycystic Ovary Syndrome) which is one of the leading causes of infertility in women. We have to be very careful that when we’re looking at estrogen levels, you may maybe supplementing, maybe you’re not getting enough estrogen, then you need to think to yourself, well, why is this the case? What is the problem here? Typically it stems back to things like inappropriate light hygiene, so not getting enough sunlight during the day and exposing yourself to too much artificial light after dark.

Another hormone that has been linked with the issue with PCOS is something called prolactin. You can see from the name, prolactin is obviously associated with lactating. It’s a hormone that influences women that are going to be breastfeeding and influences fertility in women. If the clock gene is disrupted that is functioning and powering the secretion of prolactin, that again has been shown in clinical trials to increase the risk of PCOS and also it can impact how a woman ovulates. So it can actually disrupt the normal ovulation cycles in women.

As with most other hormones linked to reproductive health like estrogen, testosterone in men, melatonin, prolactin, they are secreted in higher levels during sleep. Then they are suppressed by inadequate sleep and inadequate sleep is actually brought about from the exposure of blue light after dark. Because you need to be able to have darkness or the absence of blue and green lights or red lights is fine to actually produce more melatonin and help you sleep better, help you then produce these other hormones. It all stems back to having that functional circadian rhythm, that biological clock. In order to have that, you’ve got to have natural light during the day, but you’ve also got to have the absence of blue and green lights after dark because, without the two, you’re really not going to have the most optimal reproductive hormone secretions that you possibly can.

There was another really interesting study that came out looking at nurses many years ago. They looked at nurses that work night shift compared with those that didn’t work the night shift and worked the day shift. What they found was that all of these nurses had a disrupted circadian rhythm. What this disrupted circadian rhythm did when they did this clinical trial was that they found that it had disturbances in menstrual function. So the female shift workers compared to the non-shift workers were more likely to report menstrual irregularity and also longer menstrual cycles. The unfortunate thing is a lot of the people that work night shifts are people that we need in society, like nurses, people work in the fire brigade, and police. What they’re doing is damaging their reproductive system and overall health and wellness by exposing themselves to blue and green light by working under all that artificial light during the night period when they should be, from an ancestral standpoint and from what the science is saying, sleeping in complete darkness and not being exposed to that blue and green light after dark.

Vanessa: It’s crazy that we have people working those shifts because there has been quite a bit of evidence that’s come up, especially in recent years, on just how unhealthy shift work is. Hopefully, at some point, we will change that system and get people working on more of a regular work schedule.

Andy: Exactly. We haven’t evolved to be creatures of the night. We’re creatures of the day. In the society we live in today, you could probably never do away with shift work. What you can do is you can manage the light environment correctly for these people to actually help mitigate, not eradicate but mitigate, some of these risks and reduce down some of these risks that they’re having. Some of the worst lighting in the world is actually found in hospitals. It’s the highest in blue because of fluorescent lights. Maybe we need to look at more circadian lighting in hospitals where we have a more balanced spectrum of light present that is high in blue but also high in the greens, orange, ambers,  and reds, so it mimics the sun. Also allowing people to have more time off where they can actually be outside getting the benefits of the sun. They are missing out by working these night shifts. They’re getting all the blue exposure, no red light exposure. They are also missing out on invisible frequencies of light that are so beneficial in in moderate doses like infrared light, which is given out by the sun in the mornings and evening. Infrared is a very restorative, invisible, very instructive frequency of light that helps repair any damage caused during the day. Another thing that they’re missing out on because they would be sleeping during the day is UV light, which in moderation is used to synthesize with cholesterol in the body to produce vitamin D. Vitamin D is the most powerful vitamin/hormone that that one can produce. It’s people that have high levels of vitamin D in literally 99% of cases have lower all-cause mortality rates. It’s a shame that these people have to work night shifts, but there are a few little hacks that they could do with light that would actually make their quality of life a little bit better.

Vanessa: Right. What is so awesome is these hacks that we can do with light are relatively inexpensive, they are easy to do. It’s just a matter of changing habits. From the time that you decide, I’m ready to have a baby, I’m ready to start trying to get pregnant, I think that you just want to stack as many odds in your favor as possible. Then that’s certainly true through pregnancy and planning your birth. You want to be doing as many little things as you can, and those little things certainly add up. What can people be doing on a daily basis? I know that you’ve talked about getting outside and getting exposure to natural light. For a lot of people that go to work in an office every day, that makes that challenging. What are some things that we can be doing?

Andy: Yeah, absolutely. To tidy up your light hygiene ideally you would have periods during the day where you’re outside. You don’t need to be outside for an hour at a time. This is just two or three minutes. Because of how circadian rhythms and biological clocks work in humans is that it receives light in through the eyes and then it transcribes and photo transduces this light into something called the super charismatic nucleus in the brain, which then tells the time. In, in essence, what you need to do is as sunlight changes in its frequencies for the day, you need to lay your eyes, without sunglasses on, and not looking directly at the sun, just being outside in the light just for a couple of minutes at three major points during the day. One is ideally at sunrise, but very difficult this time of the year in the Northern hemisphere because it is winter. So within one or two hours of the sun rising, you need to be outside a couple of minutes getting that light into your eyes. What that will do is that it will help set the circadian clock and it will also help with the correct hormone secretion. What I typically say is that when people are going to work in the dark and getting to work and then having the sun rising, is to think of smokers. They get to go outside for a smoke break. You just need to say to your boss, I’m going out for my sun break. If they have a problem with that, then maybe just buy a packet of cigarettes and standout and just hold them. Although that might raise some eyebrows if you’re pregnant. You just need to do that at three points during the day. Sunrise between sort of one and two hours afterward. The second time is midday. Solar noon that’s when light is its strongest in just a couple of minutes outside then is brilliant. Then in the evening, just as the sun is setting that also sends a signal to the brain that nighttime is coming. It is really interesting because people think that sunset is all reds and ambers and that’s brilliant. That is post sunset. 20 minutes before the sunsets you get the highest spike in blue light during a 24 hour period and that signals to the brain that from now on blue light is going to diminish to zero and I can start producing melatonin. So it’s very important to try and get out of those three points during the day. That is a free hack.

It’s going to take you two minutes on each break, that’s six minutes of your day to really optimize your body clock. If people say they can’t do that, then they are lying to you. You can do that, six minutes a day is nothing. What you’ve also got to remember is that you need to then block other frequencies of light when they shouldn’t be entering your eyes in order to maintain that healthy circadian rhythm and that healthy hormone production. If you’re going to work in the morning and it’s dark, you need to not be allowing too much blue light into your eyes, because the first light you should be seeing really is the sun. So this is why we always say to wear your blue light glasses if artificial light is on.

We have clear ones or yellow ones for during the day that you can wear when you’re under artificial light that stops those damaging frequencies of light from messing up your body clock and messing up your hormones. You don’t have to wear these bright yellow glasses during the day. You can actually wear these clear ones that just filter out some of the blue light and keep your body in circadian rhythm and hormones healthy. The more important shift comes when the sun sets. Because if you’re then going and looking at your digital devices, your smartphone, your laptop, your TV, or just putting on your house lights or opening the fridge, which has a light in it, and it gives out a lot of blue light. Then that’s sending another message to your brain saying it’s solar noon again.

All the LED lights are a similar intensity and composition of light in the sun, it’s solar noon. So if you’re allowing that to pass through your eyes and you’ve done all these other free amazing hacks after dark, you’re just going to disrupt your circadian rhythm. Again, you are not going to sleep. Your body is going to think it is day time. Your hormones are going to be all over the place. You’ve just got to make sure that you’re wearing red lens, blue light blocking glasses after sunset until you go to bed. What this does is it creates something called physiological darkness. Your body thinks that it is completely dark. You can still see fine through them, it just changes blue colors to black and it changes greens to a different shade of green. All the other colors are all the same. What that does is it allows your melatonin to be secreted correctly, which is the cornerstone of having optimal reproductive health. It is going to help you get better sleep, which in turn is going to allow for more optimal estrogen and prolactin secretion.

Another good hack to do as well as is using salt lamps. I mentioned earlier about there being too much blue light during the day and not enough red light. Well, a lot of people that come to us, we recommend getting a basic salt lamp, having it next to your desk, having it next to your laptop because it gives out pinks and reds and restorative colors of light. You can have that next to your computer while you are working. That is another hack that helps mitigate any of the negative effects of the artificial blue light during the day.

A lot of people take it one step further and when they’re watching television at night, they don’t have the lights on. They would have their blue light blocking glasses on, but they would also have salt lamps around the house or red light bulbs in certain lamps, which doesn’t impact melatonin secretion. A lot of talks I’d been giving recently on how to help new moms, new dads and babies, circadian rhythms. A lot of people get up in the middle of the night and feed their babies, but they turn on all the lights. What is that is saying to mom, dad and baby? It is saying, it’s noon again, let’s keep cortisol levels high. Let’s, suppress melatonin and mess up estrogen, prolactin, and all the other hormones that are associated with circadian rhythms.

What we suggest is that in your bedroom or in the baby’s room, having a red light present. Because when you go and do that feed in the night and put a red light on, your baby’s circadian rhythm isn’t going to be disrupted. Mom and dad’s circadian rhythms aren’t going to be disrupted. Melatonin levels won’t be impacted at all and you’ll go straight back to sleep. There are so many cool hacks you can do to really mitigate the damage and disruption that blue light is going to be causing. Especially when, as you said, you want the odds stacked in your favor when you’re trying to conceive. By doing all these relatively simple hacks, you’re going to really elevate your hormonal profile to be able to have a better percentage chance of conception.

Don’t think this all just comes to women. I know that probably the majority of your listeners will be women, but they will all have partners because that obviously planning to have a baby so it doesn’t stop with females. It’s males as well. And there’s a really interesting stat that men who sleep too much or not enough, a 42% less likely to conceive with their partner. So just think about that. It’s almost 50% less chance to conceive if they’re laying in too long in the morning or if they’re going to bed too late, if they’re not getting enough sleep. Sleep is so key for men as well. They need to be doing these hacks too and wearing the blue light glasses after dark and being outside during the day.

There’s another really interesting study on testosterone levels, another hormone has been linked to circadian rhythms. Men with low testosterone levels have been shown to produce lower sperm counts, not good if you’re looking to conceive. Two factors that have the biggest impact on testosterone is chronic stress, which is caused by disrupted cortisol cycles. As we mentioned earlier, blue light during the day keeps cortisol levels high. But if you look at blue light after dark, your cortisol levels are going to remain high. What happens if you keep something chronically high is it you become resistant to it. You have too much of it in your body so you feel stressed, depressed, anxious. So that’s an issue for many men and that then has an effect and reduces testosterone levels and poor sleep. People that have and report that they have bad sleep have lower levels of testosterone.

It is really interesting as well because the quality and quantity of sperm seems to also run on its own circadian rhythm. In recent academic literature, semen collected before 7:00 AM had a much higher sperm count and concentration when compared with semen collective much later in the day. If you’re looking to conceive from a circadian standpoint, the timing of having sexual intercourse should probably be upon waking. A lot of people think, testosterone levels are highest at night. When you look at it from a healthy circadian standpoint, the quality and quantity of the sperm and the testosterone levels are actually higher in that morning period. That’s probably the time you want to be having sexual intercourse in order to try and conceive.

Circadian rhythms can be seasonal so they can have a seasonality to them. When you look at studies looking at human sperm counts the highest levels and highest qualities of sperm actually increased through spring and decreased during the summer. In the Northern hemispheres, now you’re about to go into spring. It’s the perfect time to try and conceive. It makes complete sense because look at nature, look at other animals in nature. They always reproduce in spring. There is a real, sort of deep-lying ancestral sort of wisdom in all this as well. This technology is fantastic that we live with today, but the light that is being given out by it, not to mention the EMF and wifi and things like that, it’s really disrupting our clock systems, messing up with our hormones and then just giving us not the optimal edge in order to be able to have a healthy, happy conception and a healthy maturing fetal circadian clock as well.

Vanessa: It is interesting. I use night-shift on my phone, I use Flux on my Mac. There are all these programs and apps that can help reduce blue light. Let’s talk a little bit about the glasses and why those block blue light better than just using flux on your computer or using night-shift on your iPhone.

Andy: You just beat me to. I was gonna say that if you go to my YouTube, you can actually check out, we work with optics labs with, with our glasses. We have spectral equipment that is really expensive equipment that measures the spectral output of light from any device. We have tested night-shift mode from Apple. It is great for during the day because it reduces blue light, but it doesn’t block it completely. After dark, if you’ve got night shift mode on and no blue light blocking glasses, there is still blue light present in that night shift mode. Which basically means it’s going to be sending the wrong messages to the brain. So you’ve got to be careful with looking at some of this software. I think that great for during the day, but after dark, you’ve got to eliminate 100% of blue in the 400 to 550nm range, which also covers some green light as well.

The brain and the body clock doesn’t care if you block 99% of that light or you block 0% of that light. It still sends the wrong messages to the brain and it still disrupts your sleep and hormones. This was why we founded BLUblox. We tried out a lot of blue light glasses, some of these amber lens glasses. Some of them had yellow and some of them were even clear and they were saying wear these after dark to help with your sleep. We ran 20 of the most well known brands through a spectral analyzer and not one of them blocked in line with what the academic literature, peer-reviewed studies were saying you had to block 100% of. So that’s why we created sleep plus glasses.

These glasses take the exact range of light that has been shown and proven in academic studies to disrupt your melatonin and destroy your sleep. We have created a tint that blocks only those frequencies of light. We initially did what everyone did, we went and looked in China for this kind of technology because you can get it produced cheaply. They could not produce this because they don’t work in optics labs, they were all factories. That is why our product is made in Australia because we could go down to the labs, we could sit in with these lab technicians and engineers and actually produce a specific tint based on academic literature. That is what really differentiates us from everyone else because everyone buys these orange glasses in bulk from China, slaps their logo on it and then calls them blue blockers. When in fact 100% of the time they’re not even blocking all blue lights. So you’re not going to be helping you sleep in the slightest. It’s really clever marketing and someone that has founded companies with no regard or understanding of quantum biology and how light affects human physiology. We wanted to put science and evidence into our products. We wanted to make them in optics labs and we didn’t want to block too much or too little light. That was how sleep+ lenses were born. You just wear them two to three hours before bed and it optimizes melatonin production which helps you sleep, which also helps testosterone levels for men. It helps estrogen, prolactin, melatonin levels for women. And all you have to do is put them on two hours before bed, nothing else. You can carry on using your smart phone, watching TV, having your house lights on, no issue.

Then we, we wanted to produce a couple of pairs of glasses for during the day as well because obviously blue light needs to be managed differently during the day. You don’t want to block blue light during the day. As I mentioned, it’s so good for keeping your cortisol levels high, which is what you want during the day but also keeping neurotransmitters like dopamine and serotonin from being produced. We created this clear lens that brings down the blue light a little bit because as I mentioned at the beginning of the conversation, Vanessa, that’s just too much blue light in our world at the moment. So you want to reduce it down during the day. So that’s why we got the clear blue light glasses that have a technology infused in them that basically repels about 30% of the blue light, which helps you from not getting digital eye strain, sore eyes, headaches during the day. Then we thought, we saw as well that some people have a sensitivity to artificial light during the day. And I was one of them. I used to suffer really badly from migraines. And then I also had sort of periods of quite high anxiety and that shows that you’ve got a sensitivity to light. So we created these yellow lenses to watch and the day that filter about 50% of the blue light. So it’s a little bit more than the clear ones, but if you’ve got a sensitivity to light, you’re getting migraines, feeling stressed and anxious all the time, then you’ve probably got a sensitivity to light and you need a bit more blue light filtration during the day. So that gave us our summer glow lenses. And actually a lot of people have been using them to combat seasonal effective disorder, which is a major issue in Northern hemisphere winters.

We also found because we are all geeks over here at BLUblox and we always troll through the academic literature. We actually found that if the light hits your eyes, even when they are closed, when you’re sleeping, it impacts melatonin and estrogen levels. That is just insane because what happens if we’re sleeping in a dark room but cars drive past and the headlights shine through or the neighbor has lights on or a security light goes off outside or the street lights or a partner gets up to use the bathroom during the night and switches on the light? That is going to impact melatonin and estrogen, testosterone, all these hormone levels. This is where we produced a sleep mask as well could REMedy which is 100% light blocking, which not many other sleep masks can boast because light passes up through the nose areas and in through the top. We created this sleep mask that has adjustable eyecups. You can fully open your eyes while wearing this mask. And it’s still 100% blackout. We also wanted to reduce any high pressure because if you were asleep master, that doesn’t allow you to open your eyes fully. It places pressure on your eyes, which can lead to things like glaucoma. You have got to be very careful with pressure on the eyes. That was when REMedy was born.

We have now managed to help so many people with these products. As you know, I always encourage people just to jump on a home page and check out all the five-star reviews from people that are just like, wow, I had insomnia or you know, I couldn’t sleep. I had no energy. I use these when I was looking to conceive and wow, they were amazing. So many real life testimonials on there for people that have just been amazed by these glasses because a lot of people will be listening to this Vanessa and thinking like really is light that much of an impact? It is very much like diet until you change it and adopt a healthier way of eating you don’t know. With managing your light hygiene, you don’t realize how bad it actually is. I always encourage people to get our products. They ship free worldwide. You have 30 days once you’ve received it to try it. Otherwise, you can send it back for free exchange. You’ve got nothing to lose, but you know, until you try them. Honestly, it’s just game changing.

Vanessa: I completely agree. And I’ve been wearing the glasses, which definitely took a little bit getting used to for the first few days. I’m often on my laptop at night. That’s usually when I’m nerding out and reading a ton of research and preparing for episodes. Even with having flux on my computer, I still have lights on in the house. I track my sleep with an Oura ring and I’ve been looking at what my sleep looks like since I’ve been wearing these glasses and I am getting more REM sleep and more deep sleep. I think that it’s definitely helping my sleep quality, which is really nice. I also love the sleep mask. I recently took a red-eye flight from the West coast to the East coast and put the eye mask on for the flight and slept almost the entire flight, which was awesome. The REMedy mask completely blocked out the light. It was really comfortable. I’m a big fan of your products and like anything, you know, I do my research and I don’t want to be purchasing products that I think are going to solve a problem if it’s not an evidence-based thing. That is why I’m so glad you came on the podcast today. You really know your stuff with all of the research out there and we will definitely link up to all of the studies that you’ve mentioned. You also have a great blog post that breaks down everything with fertility and pregnancy and a lot of what we’ve talked about today. I’ll link to that too. Andy, before you go, can you talk a little bit about breast milk and pumping it or breastfeeding your baby at different times of the day?

Andy: Absolutely, I’m glad you brought that up. It is such an amazing study that’s hot off the press. They did a study about three months ago where they wanted to look into something called chrono nutrition. What that means is when a baby is born a baby doesn’t have a circadian rhythm for about three months. Hence why light management is very important in those first three months of the baby being out of the womb. Now what they wanted to look at was, were there other factors that impact the developing baby’s circadian rhythms outside of light. What they did was they took breast milk that was pumped during the day and they took breast milk that was pumped after sunset. The breast milk that was pumped during the day contains quite high levels of cortisol and nothing much else from a hormonal standpoint. What you can see is that the baby would basically be given breast milk naturally during the day, high in cortisol. What was I talking about earlier during the day? We need cortisol levels to keep us alert and awake. But we don’t want cortisol levels after dark. So if you were giving your baby breast milk, that was pumped during the day, in the middle of the night, that cortisol spike will keep the baby from going back to sleep quicker. It will keep them feeling alert and awake and it will tell the baby’s developing circadian clock that it’s daytime. It would take longer to mature properly the circadian clock, but also could actually cause damage to the circadian clock and cause hormonal issues later on in life.

On the flip side, they also, as I mentioned, took readings on breast milk pumped after dark, and they found that it was devoid of cortisol but very high in tryptophan and in melatonin. If you were giving your baby to breast milk pumped after dark, in the day, tryptophan and melatonin basically cause you to be sleepy so the baby would want to sleep during the day more and be more awake during the evening. What I mentioned earlier was serotonin mixes with tryptophan and helps produce more melatonin. What you need to be mindful of is that breast milk actually influences the circadian rhythms of infants. You just got to make sure that if you’re pumping breast milk, which is a modern thing to do now because you know, we share responsibilities between both partners is that if mom or dad are getting up to do a night feed, don’t reach for the bottle that was pumped during the day. Make sure we labeled them day or night or the time that they were pumped. You want to be giving your baby breast milk is high in tryptophan or melatonin in the night because it’ll get back to sleep quicker and the baby will develop a proper circadian rhythm. During the day make sure only gave the baby breast milk pump during the day because you don’t want to be given the baby tryptophan or melatonin they would just be sleepy all the time. You want the baby to sleep better at night so you can sleep better at night and everyone’s happy. Yeah, it was absolutely fascinating that this thing exists. It’s chrono nutrition and you know, this kind of thing won’t be public knowledge for at least five to 10 years because that’s how long it takes for studies to come out. Whereas, Vanessa and myself, have had the privilege of actually being able to look at the study and read it prior to it going all through all the stages it needs to go through to actually get in the public domain. So there you go. Breast milk and chrono nutrition, make sure that you only give your baby breast milk pumped at specific times of the day.

Vanessa: That’s such a good tip. And so easy to just label it whether it was pumped in the morning or at night. Milk production tends to be highest in the morning. If you are pumping breast milk and trying to build up a stash of milk in your freezer, a lot of times you’re going to be doing that extra pumping session first thing in the morning. If you’re waking up before the sun is coming up, is that milk going to be high in cortisol? I guess if you’re waking up and turning on lights in your house you are giving yourself blue light exposure and in that case, would the milk be higher in cortisol?

Andy: Yeah. You get something independent of light that happens in the morning. When you wake up, what gets you to wake up? It’s a cortisol awakening response which spikes your cortisol extremely high. Typically it is due to the rising sun that stimulates that. If your circadian rhythm is functioning on a specific cycle, it will still happen at a specific time of the day.

There are also a lot of arguments out there, and this is probably partially related to babies, but probably not so much because they do need feeds. This is definitely true for adults that the time they eat optimally for correct hormone and neuropeptide and neurotransmitter release to actually digest that food during daylight hours. In the evenings our bodies aren’t primed to utilize that. The nutrients found in products are digested more as efficiently if we were to take them during the day. Also, digestion gets in the way of adult circadian rhythms as well. It’s a very interesting point that that you make that maybe more research is needed to look into the optimal feeding patterns. Looking at it from a circadian standpoint because circadian rhythms are governed by light. We haven’t dived deep into this today, but every cell in our body has its own peripheral clock and these work in unison with our master body clock and each of those clocks is governed by either light, exercise, temperature or food timing. The liver and pancreas clock and stomach clock systems are all governed not by light, but by the time from a circadian point of view that we actually ingest those calories.

The way it works is that there’s an old adage that goes around that eat breakfast like a king, lunch like a prince, and dinner like a pauper. That’s the most optimal way to eat from a body clock perspective. I wonder if more studies need to be done on feeding of infants because like you pointed out, breast milk production is highest during the day. Maybe we need to look into that and maybe there’s a reason for that. From an evolution perspective, why is it higher during the day? Is it because our ancestors would have only fed the baby during the day and not during the night? And if they did do that, did that mean they sleep longer periods during the night so they didn’t have to feed them as much during the night? There are definitely a lot of questions to be asked and answered around that for sure. It’s a really good point.

Vanessa: The more that I dig into the research, especially with pregnancy, there’s so much limited research because a lot of times expecting mothers are excluded from clinical trials. The more I dig into it, the more you find that more research is needed and how little we really know about all of this stuff. I think over the last, decade or a couple of decades, what we do know is expanding so rapidly. It’s so awesome to get to bring you on the podcast and pick your brain and have you share all of this research with us. There are so many really easy hacks you can do to block out a lot of the blue light and improve how you are sleeping and your fertility.

Andy: Absolutely, I think if people just blocked out blue light after dark and got out in the sun for six minutes during the day at three different intervals you would see a massive improvement in your wellness and health and how you feel.

Vanessa: That is such a simple easy thing to do. Thank you so much Andy. We do have a promo code so you can save 15% on the BLUblox website. That promo code is PREGNANCY. I’ll link that and everything else in the full article that will accompany this episode. We will do a transcript. Andy, thank you again so much for coming on. Is there anything else we are leaving out that you want to add in?

Andy: Vanessa, I think we could talk for hours on this. I think those are the main key takeaways that we discussed today. Just make sure if you optimize your light you’re going to optimize your life. Take those steps today and make yourself a more optimal you tomorrow if you do those steps.


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