Aaron Hartman, MDFunctional Medicine Specialist | Clinical Researcher

How Light Exposure Affects Your Hormones #shorts

20 Apr 2026 · 1 min

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0:34

Dr. Aaron Hartman explains how light exposure controls your hormones. Morning sunlight raises testosterone, thyroid activity, and cortisol to wake you up. Blue light from screens in the afternoon and evening suppresses the normal drop of these hormones at night, disrupting your system and causing fatigue.

Chapters

How much sunlight you get exposed to is a big deal. You know, the lights I'm using right now for this podcast are also— I'm getting overloaded with blue lights. Actually, after a day of this kind of stuff, I'm really fatigued and tired. I need to get outside in the sun. Why? Because these are messing with my body's natural circadian rhythms. Well, guess what? Daylight cycles, you make more testosterone, sex hormones in the morning. You get a bump in your thyroid and your cortisol in the morning. You want these to come down at night. If you're flipping that by exposing yourself to tons of blue lights in the evening and afternoon, all of a sudden it will impact. Your neurohormonal gastro-neural endocrine hormonal system,