Neuroscientist Dr. Andrew Huberman highlighted the critical connection between morning sunlight and healthy hormone rhythms in a recent post, emphasizing the importance of early light exposure for optimal energy and sleep.

“Bright light viewing ideally from sunlight in the morning amplifies your natural (and healthy) am cortisol rise,” said Dr. Andrew Huberman in a post on X. “You want that in the early day. Fail to get it and you’ll likely late shift your cortisol peak or get a second one in the pm which is not good for sleep or health.”

Huberman has long advocated for light hygiene—intentional exposure to natural light at the start of the day—as one of the most impactful and underused tools for regulating sleep-wake cycles. Early morning sunlight stimulates the body’s natural cortisol release, supporting wakefulness, focus, and metabolic function.

Without this exposure, cortisol release can shift later in the day or surge a second time in the evening, which disrupts sleep quality and may contribute to long-term hormonal imbalance.

Dr. Andrew Huberman is a professor of neurobiology and ophthalmology at Stanford University and host of the popular Huberman Lab Podcast. His work focuses on how behavior and environment shape brain function, stress regulation, and mental performance.