A presenter tested whether sunlight boosts testosterone by spending a week covered up, then a week shirtless in the sun. His levels dropped in darkness and rose with sun exposure. UVB radiation appears to drive the effect, possibly because ancestral humans needed peak libido in summer so babies arrived in spring.
You can boost your testosterone with sunlight, and I'm going to prove it to you. I spent a week hiding from the sun like a little Gollum. When I went outside, I put on this black hoodie just to minimize my sunlight exposure, and my testosterone dropped rapidly. And then I reversed it. I spent a week deliberately increasing my sunlight exposure. I went outside shirtless as much as possible, or with a sleeveless shirt, and my testosterone jumped up substantially. But how does this work? And more importantly, why does it work? It comes down to UVB light, which has been shown measurably to increase testosterone in both animals and humans. And if you think about it from an evolutionary perspective, it actually makes a lot of sense. Consider, during evolution, humans would ideally want to conceive offspring when they had the highest chance of survival, meaning babies should be born in the spring so they're not heading right into a winter. That also means you want sex hormones and libido to peak roughly 9 months earlier. And if you do the math, that places you around July and August when UVB exposure from the sun is the strongest because it's right overhead. So now we have human evidence, my evidence, and evolutionary logic all explaining why sunlight can boost testosterone. But that's not even the craziest part. You can even hack your partner's brain with sunlight, and I'm going to show you how. Just click this link and subscribe for more.
