VitalSun

👉 Download VitalSun TODAY on iOS and Android: vitalsun.app ⠀ It tells you exactly when to get sunlight for better sleep, energy, and mood, based on your location and your day. ⠀ ☀️ A personalized sun routine built around your schedule 📊 Live sunlight data showing what light is available right now 📈 Exposure tracking so you can see your habit build ⠀⠀ 👉 Get it now: vitalsun.app

The sun isn't the same light all day. It changes hour by hour, and so does what it does for your body. ⠀ 🌅 Sunrise ⠀ • Mostly red and infrared, with almost no UV • The sun is low, so the sky is blue while the sun glows orange • That contrast is the strongest "the day has started" signal your body clock gets ⠀ Best for: setting your clock, getting your energy going and timing your sleep for tonight ⠀ ☀️ Early morning ⠀ • UVA starts showing up about an hour after sunrise • UVA releases nitric oxide from your skin, relaxing your blood vessels • It also pulls your melanin up toward the surface, prepping your skin for the stronger sun later ⠀ Best for: gentle UV and building up your skin ⠀ 🔆 Midday ⠀ • The sun is at its highest and brightest • UVB finally makes it through, the only part of the day your skin can make vitamin D • The strongest light of the day gives your mood and alertness their biggest boost ⠀ Best for: vitamin D, mood and alertness. Keep it short and never burn. ⠀ 🌤 Afternoon ⠀ • UV starts fading, UVB first and then UVA • Red and infrared take over again ⠀ Best for: a sun break to beat the afternoon slump ⠀ 🌇 Sunset ⠀ • Low sun again, with blue sky against orange light • Your clock reads it as the end of the day • It also makes indoor light at night bother your sleep less ⠀ Best for: winding down and protecting your sleep ⠀ 🌙 After dark ⠀ • No sunlight at all, which is exactly how it should be • Your eyes are at their most sensitive now, so even room light can push back your melatonin ⠀ Best for: dim lights, a dark bedroom and real sleep ⠀ Same sun, six different signals. The trick is catching the right one at the right time.

Your sunlight wavelength cheat sheet ☀️ ⠀ UVB (280 to 315 nm) • Makes vitamin D in your skin • Builds new melanin, your lasting tan • Triggers beta-endorphin, the feel-good hormone • Only shows up when the sun is high, around midday ⠀ UVA (315 to 400 nm) • Releases nitric oxide from your skin, relaxing blood vessels and lowering blood pressure • Pulls existing melanin to the surface, your quick glow • Shows up about an hour after sunrise and sticks around all day ⠀ Violet (about 380 to 420 nm) • Picked up by a light sensor at the front of your eye called neuropsin • Linked to healthy eye growth in kids • Mostly missing from indoor lighting ⠀ Blue (about 450 to 490 nm) • The main signal your body clock reads • Boosts alertness and mood during the day • Pushes back melatonin at night ⠀ Yellow and orange • At sunrise and sunset, your eyes compare them against the blue sky • That contrast tells your clock what time of day it is ⠀ Red (about 620 to 700 nm) • Supports your mitochondria, the energy makers in your cells • Works best in the morning • Dominant at sunrise, with almost no UV ⠀ Near-infrared (700 nm and up) • Penetrates deep into your body, even through your chest • Together with red, it makes up more than half of sunlight • There all day, even when it's cloudy ⠀ Every one of these comes free in sunlight, all at once. ⠀ A lamp gives you one or two. The sun gives you the full set.

Sunlight isn't the same all year, so the way you use it shouldn't be either. Here's how to get the most out of every season: ⠀ Spring ⠀ • Build your base slowly. Your skin has barely seen UV all winter, so start with short sessions and add a little more each week ⠀ • Lean on mornings. Early sunlight is mostly red and infrared, and it helps prep your skin for the stronger sun that's coming back ⠀ Summer ⠀ • Use the shadow rule. When your shadow is shorter than you are tall, the sun is strong enough for UVB, and in summer that window is wide ⠀ • Keep midday sessions short and never burn. It's the strongest sun of the year ⠀ • Stock up on vitamin D. For a lot of people, what you build in summer is what carries you through winter ⠀ • Don't forget sunrise. Long days make it easy to skip the morning sunlight that sets your body clock ⠀ Fall ⠀ • Grab the last of the UVB. Once you get far enough north, the sun stops climbing high enough for it as the days get shorter ⠀ • Use the time change. When the clocks fall back, sunrise moves earlier, so a lot of people can finally catch it before work ⠀ • Test your vitamin D in October. It shows you what summer left you with ⠀ Winter ⠀ • Go outside anyway. A gray winter sky is still about 20x brighter than indoors and still surrounds you with red and infrared ⠀ • Stay out longer when it's cloudy, around 20 minutes or more in the morning ⠀ • Protect your mood. Less sunlight is tied to low energy, low mood and carb cravings, so get out every single day ⠀ • Chase the sun if you can. A trip somewhere sunny is a chance to rebuild your levels, as long as you build up slowly

Had a rough night of sleep? The light you sit in the next day might decide how bad it feels. ⠀ Researchers put 16 healthy adults through 2 nights of only 5 hours of sleep. Then they split them into two groups for the next afternoon: ⠀ • One group sat in bright light from noon to 5pm ⠀ • The other group stayed in dim light the whole time ⠀ Here's what the bright light did: ⠀ • People felt less sleepy ⠀ • They had fewer of the slow eye movements that happen when you're starting to drift off ⠀ • Their reaction times on an attention test got better ⠀ And the interesting part: it didn't work by shutting off melatonin. The bright light boosted alertness through a completely separate pathway in the brain. ⠀ Now here's what makes this so relevant. The "bright light" in this study was 1,000 lux. ⠀ • A typical office is about 500 lux ⠀ • A cloudy day outside is at least 10,000 ⠀ • A sunny day can be 100,000 or more ⠀ So even a gray afternoon outside is about 10 times brighter than the light that helped these people stay sharp on short sleep. ⠀ Next time you're running on a bad night, don't hide inside. Get outside into the brightest sunlight you can find.

Retatrutide is everywhere right now. It's being called the next big weight loss drug because it hits three hormone pathways at once instead of one. ⠀ But your body already runs its own multi-signal system for appetite and energy. And one of the biggest inputs is free: light. ⠀ Here are three levers sunlight pulls: ⠀ 1. When you get your light ⠀ In one study, people whose bright light came earlier in the day had a lower BMI than people who got it later, even after accounting for how much they ate, how active they were and when they slept. ⠀ Morning light helps time your metabolism for the day. ⠀ 2. Light on your skin ⠀ In mice fed a high-fat diet, regular low-dose UV on the skin slowed weight gain and improved blood sugar, insulin resistance, fatty liver and cholesterol. Vitamin D alone didn't do the same thing. ⠀ UV also switches on a molecule in your skin called POMC, part of the same system your brain uses to dial down appetite. ⠀ 3. Eating while the sun is up ⠀ Your gut runs its own clock, and it reads food. Eat late into the night, and it thinks it's still daytime while your brain knows it's night. ⠀ Your body also handles sugar best earlier in the day. The same meal at 9pm hits your blood sugar harder than it would at noon.

Heading somewhere tropical this winter? Here's how to soak up all that sunlight without getting torched on day one. ⠀ First, know what you're walking into. Your skin has probably barely seen real sun in months, and now you're flying somewhere the sun sits almost straight overhead. That combination is exactly how people end up lobster red the first afternoon. ⠀ 1. Start the first morning early ⠀ • Get outside as close to sunrise as you can ⠀ • That early sunlight is mostly red and infrared with almost no UV, and it helps prep your skin for the stronger sun later in the day ⠀ • It also helps reset your body clock if you crossed time zones ⠀ 2. Build up slowly ⠀ • Keep your midday sessions short the first few days, then add a little more time each day ⠀ • Your skin builds melanin gradually, your own built-in protection, but it can't do it overnight ⠀ • Going from a fully indoor winter straight to a beach day is the biggest burn risk there is ⠀ 3. Use the shadow rule ⠀ • If your shadow is shorter than you are tall, the sun is strong enough for UVB ⠀ • In the tropics, that's true for a big chunk of the day, not just a little window around noon ⠀ • So that's when you want to be most careful with how long you stay out ⠀ 4. Know your skin ⠀ • If you're fair or a redhead, your safe window is much shorter ⠀ • Darker skin can handle more, but it can still burn ⠀ 5. Stop before you turn pink ⠀ • Pink means you've already gone too far ⠀ • Once you've had your dose, move into the shade or cover up ⠀ 6. Enjoy the shade too ⠀ • Shade still surrounds you with red and infrared bouncing off everything around you ⠀ • You don't need to be in direct sun all day to get a ton of the benefits ⠀ And the best part: if you live somewhere that gets no UVB all winter, this trip is a real chance to bring your vitamin D back up. Just do it slowly.

The problem with seed oils might not just be the fat. It might be the heavy hydrogen hiding inside them. ⠀ It's called deuterium. ⠀ • Normal hydrogen = 1 proton • Deuterium = 1 proton + 1 neutron ⠀ Same charge. Twice as heavy. ⠀ It's naturally in everything you eat and drink, about 150 out of every million hydrogen atoms. ⠀ So why would that matter? ⠀ Your cells have a tiny motor ⠀ Inside every cell, your mitochondria make energy using a spinning motor. ⠀ Hydrogen flows through it. Every spin makes ATP, the energy your body runs on. ⠀ Now picture balls rolling through a hose. ⠀ Normal hydrogen rolls right through. Deuterium is twice as heavy. ⠀ The theory: when it gets in, it jams the motor and slows it down. ⠀ Where seed oils come in ⠀ People who follow this idea say some foods load you up with more deuterium. The two they point to most: ⠀ • Seed oils • Tropical fruit eaten far from where it grew ⠀ Their go-to example: pineapple from Ecuador in a New York winter. Lots of deuterium, very little sun to balance it out. ⠀ Where sunlight comes in ⠀ The proposed fix is light. ⠀ Sunlight, especially red, infrared and UV, helps your mitochondria run more efficiently, so they can push through the extra load. ⠀ Less sun + more deuterium = a motor that struggles. ⠀ The honest part ⠀ This is still an early, controversial idea. Deuterium and the motor are real biology. Whether everyday deuterium from food causes disease hasn't been proven. ⠀ But the advice that comes out of it is hard to argue with: ⠀ ☀️ Get real sunlight every day 🥩 Cut back on seed oils 🍍 Eat local and in season

Everyone's suddenly talking about ApoB. But almost nobody mentions that your cholesterol has seasons. ⠀ ApoB is a count of the particles that carry cholesterol through your blood, like LDL. The more of them floating around, the higher your heart risk tends to be. ⠀ Here's the part that rarely comes up: blood lipid levels tend to be at their lowest in summer, when people get the most sun. ⠀ Why would sunlight touch cholesterol? ⠀ 1. Your skin makes vitamin D out of a cholesterol-based molecule ⠀ UVB hits it, breaks open its ring structure and turns it into vitamin D. One leading theory is that when you're getting regular UVB, your body pulls cholesterol out of circulation to keep making it. ⠀ 2. Sunlight protects your blood vessel walls ⠀ UVA releases nitric oxide stored in your skin. That relaxes your blood vessels, lowers blood pressure and helps protect the inner lining of your arteries from what's floating in your blood, including LDL. ⠀ 3. It shows up in the bigger picture ⠀ In mice fed a high-fat diet, regular low-dose UV lowered fasting cholesterol and slowed weight gain. And in a 20-year Swedish study, women who avoided the sun had higher death rates from heart disease.

This Sunday the clocks fall back an hour, and most people are only thinking about the extra hour of sleep. ⠀ But the bigger win is what happens to your mornings. ⠀ Sunrise is about to show up an hour earlier on the clock. For a lot of people, that means the sun will finally be up before they leave for work, instead of rising while they're stuck in traffic or already sitting at their desk. ⠀ That's a big deal, because morning sunlight is the most important sunlight of your whole day: ⠀ • It clears out the leftover melatonin making you groggy ⠀ • It times your cortisol spike so you actually feel awake ⠀ • It starts the timer that gets you sleepy at the right time that night ⠀ And the switch also takes an hour of sunlight away from your evenings. Less evening light can drag on your mood and sleep, which makes that morning sunlight even more important to grab. ⠀ So use it: ⠀ • Get outside within 30 to 60 minutes of waking ⠀ • Take your coffee, a walk or the dog out while the sun comes up ⠀ • Aim for 10 to 15 minutes if it's sunny, 20 or more if it's cloudy ⠀ • Skip the sunglasses ⠀ For a few weeks, you get a sunrise that lines up with your morning. Don't sleep through it.

Bright light in the morning raised people's cortisol by more than 50%, almost instantly. The same light in the afternoon did nothing. ⠀ Here's the study. ⠀ Researchers kept 8 healthy men awake through the night, in dim light, and measured their hormones every 15 minutes. Then they changed one thing: ⠀ • In one version, the men got 3 hours of bright light early in the morning, from 5 to 8am ⠀ • In another, they got the same bright light in the afternoon, from 1 to 4pm ⠀ • In the third, they stayed in dim light the whole time ⠀ Here's what the morning light did: ⠀ • Cortisol jumped by more than 50%, right away ⠀ • Melatonin, the sleepy hormone, got shut down ⠀ • And even after a full night with no sleep, the men stayed noticeably more alert ⠀ The afternoon light? No effect on hormones or alertness at all. ⠀ A separate study backed it up. Men exposed to bright light right after waking had about 35% more cortisol in the first hour than men who woke up in the dark. And the same light in the evening didn't change cortisol at all. ⠀ That's the key: timing. Your body is primed to respond to light in the morning in a way it simply isn't later in the day. ⠀ Cortisol gets a bad rap, but that morning spike is your body's natural wake-up signal. It's what gets you out of grogginess and sets up your energy for the whole day. ⠀ So the most powerful sunlight of your day might be the first sunlight of your day.

Winter sunlight rules: ⠀ 1. Short and often beats long and freezing 2. 5 minutes outside still counts 3. Step out right after sunrise, even just to the porch 4. Take your morning coffee outside for a few minutes 5. Leave the sunglasses home 6. Bundle up, but keep your face uncovered 7. Use the daylight your commute gives you 8. Park at the far end of the lot 9. Take the long way from the car to the door 10. Step outside during the warmest hour of the day 11. Get your errands done before it gets dark 12. Snowy days are brighter than you think 13. Gray days still count 14. Move your desk next to the brightest window 15. Open every blind the second you wake up 16. Make one weekend block outside while the sun's up 17. Ski, skate, sled or hike, it all counts 18. Know when the sun sets, because it's early now 19. Keep your wake time the same every day 20. Don't sleep in to make up for dark mornings 21. Eat dinner earlier, since it gets dark earlier 22. Dim the lights once the sun goes down 23. Keep your bedroom pitch black 24. Don't panic when your tan fades 25. Consistency beats perfect weather

Every food you eat started as sunlight. ⠀ Plants turn sunlight into energy through photosynthesis. Animals eat those plants. So even a steak is sunlight, just a few steps removed. ⠀ Take that idea one step further, and food becomes a "barcode of sunlight," carrying information about the light and season it grew in. When you eat it, your body reads that information. ⠀ So what happens when that barcode doesn't match where you are? ⠀ Take a banana ⠀ Most bananas sold in the US are grown in places like Ecuador, right on the equator. ⠀ There, the sun climbs almost straight overhead at noon. Days stay close to 12 hours long all year. UV is strong every single day. A banana there grows in endless summer. ⠀ Now eat that banana in Boston in December. ⠀ • You get only about 9 hours of daylight • At noon, the sun barely clears a quarter of the way up the sky • There's almost no UVB at all ⠀ Your eyes and skin are telling your body it's deep winter. The banana is telling it it's endless summer. ⠀ It's like trying to get Ecuador's sun in the middle of a Boston winter. The signal doesn't fit where you are. ⠀ Why the mismatch matters ⠀ In nature, sweet fruit shows up in summer, when the days are long and bright. Your body expects sugar and strong sunlight to arrive together. ⠀ In winter, with dim days and little UV, the thinking goes that tropical fruit stops acting like a health food. Instead of fitting the season, it sends a summer "store energy" signal to a body that's getting winter light. ⠀ People who follow this idea link that mismatch to: ⠀ • More fat storage, especially around the middle • Blood sugar swings • Feeling off, with more colds and gut issues in winter ⠀ What eating with the seasons looks like ⠀ ☀️ Summer: lots of fruit, local produce, longer days to eat in ❄️ Winter: more animal foods, root vegetables, fewer tropical fruits 📍 All year: as local as you can get it ⠀ The bonus: local and seasonal food is usually fresher and often cheaper too. ⠀ It doesn't have to be perfect. If a certain way of eating makes you feel your best, that matters more than any rule. ⠀ But if your body's getting Boston light and Ecuador food at the same time, it might be worth asking which signal you want it to follow.

Monday through Friday, sunrise in my neighborhood is busy. People walking their dogs, people out running, parents pushing strollers. ⠀ Then Saturday and Sunday come and it's a ghost town. ⠀ Same sunrise, same sky, nobody outside. Everyone's sleeping in to catch up from the week. ⠀ I get it. But that weekend sleep-in is quietly undoing a lot of the good from the week. ⠀ Your body clock runs on consistency. Every morning that you see sunlight at the same time, your clock gets the same clear signal, and everything from your energy to your sleep that night lines up around it. ⠀ Then the weekend hits: ⠀ • You sleep in two or three hours, so your body clock gets no morning signal until late ⠀ • Your whole rhythm starts drifting later ⠀ • Sunday night you can't fall asleep, Monday morning feels brutal, and you spend half the week getting back on track ⠀ Researchers have actually measured this. Over a normal weekend at home, people's body clocks drifted later. Over a weekend living by natural sunlight, their clocks moved earlier instead. ⠀ So here's my take. If you're tired on Saturday or Sunday, don't skip the sunrise to make up for it. Get up around your normal time, get outside and see it, and then take a nap later in the day if you need one. ⠀ You get the rest, and you keep the signal that makes the whole week work. ⠀ Your body doesn't know it's the weekend. It only knows when it sees the sun.

Most people think about what they eat. Almost nobody thinks about what light they're taking in. Here's what a "light diet" looks like: ⠀ 1. Watch the sunrise outside The orange horizon against a blue sky sends a time-of-day signal to your body clock you can't get from a lamp. ⠀ 2. Take your sunglasses off in the morning Early on there's basically no UV yet, so you're only blocking the sunlight your clock needs. ⠀ 3. Stay outside as much as you can during the day Even a cloudy sky is about 20 times brighter than the inside of your house. ⠀ 4. Open your windows and doors Sunlight through glass is about 50x less effective at setting your body clock. ⠀ 5. Eat your bigger meals earlier Your liver, pancreas and gut are built to handle food in daylight, so a bigger breakfast and lunch and a smaller dinner work with them. ⠀ 6. Watch the sunset That same orange-blue contrast tells your body the day is ending. ⠀ 7. Go dim after dark Bright light at night tells your clock it's still daytime and holds back your melatonin. ⠀ 8. Skip the screens before bed Phones and TVs are bright, close to your eyes and loaded with blue light. ⠀ 9. Go to bed a few hours after sunset Your brain needs real darkness for a while before it fully switches on melatonin. ⠀ 10. Let yourself wake up with the sun Do the rest consistently, and a lot of people start waking up naturally around sunrise without an alarm.

DAY 12: Circadian analysis of Conor McGregor ⠀ He's 38, he ended a five-year layoff in July, and his knee gave out on the very first kick. The fight lasted 69 seconds. ⠀ So how does "The Notorious" do on light? Let's break it down. ⠀ Sleep: 4/10 ⠀ For most of his career, sleep was optional. Back in 2015, he put it like this: ⠀ "Sometimes I train in the middle of the night, all on my own. Can't sleep, don't want to sleep, get up, go to the gym." ⠀ He's also admitted that, at one point, he got so hooked on Call of Duty he'd play all night. When his girlfriend woke up at 8am to go for a walk, that was his cue to go to bed. ⠀ By 2022 he was preaching the opposite: "Wake up at a certain time. Train at a certain time. Structure is the key to real success." ⠀ Then this summer, he swore off alcohol for good during his comeback camp. Eight days after knee surgery, he was having a pint of his own stout. Alcohol is one of the fastest ways to wreck your sleep. ⠀ Nighttime darkness: 3/10 ⠀ Training in a lit-up gym in the middle of the night and gaming until sunrise is about as bright as nights get. ⠀ And fight night didn't help. His comeback was the main event in Las Vegas, which means bright arena lights and peak adrenaline late into the night. ⠀ Morning timing: 4/10 ⠀ Here's the line that says it all, from that same 2015 interview: "This is early for me, being here at half ten in the morning. This is really early." ⠀ He's talked up structure since, but there's still no sign of a steady wake time. And a wake time that moves around drags your cortisol rise around with it. ⠀ Morning light: 3/10 ⠀ No sign of a sunrise habit, and for years his mornings were his nights. ⠀ Daytime light: 5/10 ⠀ Most of his training happens inside the SBG gym in Dublin, under artificial light. ⠀ But credit where it's due: days after surgery, he posted a video recovering at the beach with his knee in a brace. That's exactly where a healing body should be. ⠀ Evening light: 4/10 ⠀ No sign of a sunset habit. His evenings have usually been when his day is just getting going. ⠀ Travel: 3/10 ⠀ His comeback took him from Ireland to Las Vegas, eight time zones west, for a late-night main event. ⠀ That's a massive jump for your clock, and then a long trip back east, which is the harder direction to adjust. ⠀ Location: 3/10 ⠀ He's based in Dublin, at about 53 degrees north. That means short, gray winter days and almost no UVB from roughly October to March. ⠀ If anyone on this list needs to be strategic about sunlight, it's him. ⠀ Overall: 3.6/10 ⠀ A night owl in one of the darkest places on this list. He says he's "ahead of the curve" on his recovery and aiming to return next summer. ⠀ Add some sunrises to that rehab, and his next comeback might last longer than 69 seconds. ⠀ Circadian leaderboard so far: ⠀ 1. Gary Brecka: 8.3/10 2. Andrew Huberman: 8.1/10 3. Tom Brady: 8.0/10 4. Bryan Johnson: 7.9/10 5. Mark Wahlberg: 6.7/10 6. LeBron James: 5.3/10 7. Sydney Sweeney: 5.0/10 8. Donald Trump: 4.0/10 8. JD Vance: 4.0/10 10. Conor McGregor: 3.6/10 11. Elon Musk: 3.2/10 12. MrBeast: 3.0/10 ⠀ Who should I break down next?