How does sunlight exposure affect the circadian rhythm, and how can this influence cortisol production in the body?

How does sunlight exposure affect the circadian rhythm and cortisol production?

The circadian rhythm is your body's internal clock which tells you when to sleep and when to stay awake. From regulating sleep patterns to affecting metabolism, the circadian rhythm plays a key role in your overall health. One of the fundamental elements controlling the circadian rhythm is light, specifically sunlight exposure.

Influence of Sunlight Exposure on Circadian Rhythm

The production of the hormone melatonin, which promotes sleep, is controlled by the circadian clock which is sensitive to light and darkness. During the day, sunlight exposure inhibits melatonin production, helping your body remain alert and awake. As daylight fades and darkness sets in, this inhibition ceases, allowing melatonin production to increase and promote sleepiness (National Institute of General Medical Sciences, 2021).

Sunlight Exposure and Cortisol Production

Sunlight exposure also significantly influences another hormone - cortisol. Cortisol, often known as the "stress hormone," is regulated by the circadian rhythm. Upon waking, cortisol levels will usually reach their peak within 30 minutes to an hour, a phenomenon known as the "cortisol awakening response." This response is triggered by the morning sunlight. Exposure to sunlight in the first part of the day can help stimulate cortisol production, ensuring that the body is alert and energized (Leproult R. et al, 2001).

Altering your exposure to sunlight can distort your circadian rhythm and influence cortisol production, potentially impacting sleep quality, mood, and overall health. Therefore, achieving a healthy balance of sunlight exposure is essential for maintaining optimal health.