Listen to the full episode here https://bengreenfieldfitness.com/sunlight This episode is all about light, but it's certainly not light on content! See, the last time I was in Malibu, myself, music producer Rick Rubin and today's guest - Matt Maruca of RA Optics - spent plenty of time geeking out on all things light. I've known Matt for two years now, and consider him to be one of the world's leading authorities on what is called "photobiomodulation" - or the use of specific wavelengths of light therapy to cause some very beneficial health effects, and also a guy who knows more about blue-light blocking glasses and limiting the harmful effects of artificial light than just about anyone I know. Today's episode is a special two-parter. The first section is yours truly filling you in on how sunlight makes you skinny and blue light makes you fat. The second part is a special solosode from Matt, in which he fills you in on the some little-known aspects of how to use light and how to block light in a way that will affect your energy, sleep, mitochondrial health, and much more, including history of the use of sunlight for health, why the sun and skin cancer isn’t black and white, lots of research on how light affects human biology and the benefits of sunlight, how artificial light affects the body and much more. Just to give you a "taste" of what you're about to hear: after preparing this episode, I asked Matt: "can you point me to a post or research on "best time of day to cheat if you are going to cheat" based on circadian rhythm/sun exposure? You alluded to it in the audio." He replied: "I think it would be morning/mid-day. One of the factors leading me to say this is Ayurveda which I imagine you're familiar with. An Ayurvedic doctor I started working with explained this to me in their terms. Basically, in the middle of the day as the sun is stronger, the metabolism is more active. They call this energy "pitta", or fire. So, we can burn through stuff pretty well. This is why they generally suggest eating "heavier" food in the middle of the day for lunch. And, it's a no brainer to me to fast through dinner because then the body can completely burn through everything you've consumed. As for the Western Research, Satchin Panda from the Salk Institute leads the way. I recommend watching his TED talk where he explains their experiments on mice. They basically found that mice eating healthy food when their metabolism is turning off had way more problems than mice eating unhealthy food when their engines are running full force. Because they are nocturnal the times are reversed for them relative to us. So for us the best time would be late morning to mid-day. To me, when eating this way I wouldn't even consider it a cheat because the body can move through stuff so well. If you are comparing to someone who is usually eating a "healthy" dinner at 7 or 8 PM, I am 100% convinced that it would be healthier to "cheat" every day in the middle of the day and fast through dinner then to do what that person is doing. Based on the research, there really is no such thing as "healthy food" after 5 PM or within 4 hours of sleep. During our discussion, you'll also discover: -The impact of light on human biology, for better or worse [8:10] Deleterious effects of artificial light have been well researched Recent studies show artificial light linked to breast cancer and sleep disorders Exposure to artificial bright light at night suppresses melatonin secretion and increases sleep latency (how long it takes to fall asleep) LED's are replacing fluorescent bulbs (for better efficiency) LED's cause retinal damage, cell death in eye tissue Dimming, color changing features make things worse (flicker) Flicker can cause irreversible damage to the retina Oxidative stress damage Photobiology: The study of the effects of ultraviolet, visible and infrared radiation on living organisms. Book: The Influence of the Blue Ray of Sunlight Red light used to treat smallpox in 1903 Phototherapy becomes therapeutic intervention Book: Light Therapeutics by John Harvey Kellogg Light affects metabolism mTOR in the summer; AMPK in the winter Being careful with light exposure allows you to strike a proper balance  between anabolism and catabolism -10 light biohacking tactics to optimize your body and brain [17:30] Use healthy light bulbs Color rendering index (CRI) Look for a CRI of 97 or higher in LED bulbs Lower than 3000 color temperature (kelvin) Avoid incandescents coated in white Get as much morning sunlight as possible Morning fasted walk in the sunshine Eat a diet rich in fatty acids (Vitamin A and D) Block blue light as much as possible at night 400-485 nanometer wavelength RA Optics Avoid artificial light (night and morning) Simulate sunlight as much as possible (infrared) Only use red light in the evening Candles (fragrance free, bees wax) Hidden smartphone red screen trick Use Iris Tech on all your monitors Use anti-glare computer monitor Eizo m