From influencers peddling melatonin supplements to Fortune 500 CEOs scheduling meetings around their biological clock, circadian rhythm is reshaping how we think about optimisation. But circadian biology governs far more than sleep – your skin and systems undergo distinct metabolic shifts across the 24-hour cycle. Barrier function strengthens overnight, oxidative stress peaks during daylight and collagen synthesis follows temporal patterns dictated by cellular clocks. Energy metabolism, immune signalling, and neuroendocrine balance all operate on circadian schedules.
