Morning vs. Evening Light – The Secret to Better Sleep

Aging brings many changes, and unfortunately, sleep disturbances are common. Many older adults struggle with falling asleep, waking up frequently, or feeling less rested. However, new research suggests that simply adjusting light exposure can significantly improve sleep quality.

The Impact of Light on Sleep

As people age, their eyes undergo natural changes. The lens becomes more yellow, pupils shrink, and certain light-sensitive cells decline. These changes make it harder for blue light (wavelengths between 420-480 nm) to reach the brain’s internal clock, located in the hypothalamus. Since blue light helps regulate sleep cycles, its reduced presence can weaken the body’s natural rhythm.
Moreover, many seniors spend less time in natural daylight and more time exposed to artificial evening light, further disrupting their sleep patterns.

New Study Reveals Light’s Role in Sleep Quality

A study from the University of Surrey, published in GeroScience, investigated how light exposure affects sleep in older adults. Researchers recruited 36 participants over the age of 60 who reported sleep issues. Over 11 weeks, they followed a specific routine:

Participants were exposed to either blue-enriched white light (17,000K) or standard white light (4,000K) for two hours in the morning and evening.
They switched between different lighting conditions with two-week breaks in between.
Sleep patterns, movement, and light exposure were tracked using activity monitors and sensors.
Sleep diaries and melatonin tests were used to assess sleep quality.

Key Findings: Morning Light Helps, Evening Light Hurts

The study found that the timing of light exposure significantly affected sleep patterns:

Morning exposure to blue-enriched light improved sleep stability, reducing nighttime wake-ups.
Evening exposure to blue light disrupted sleep, making it harder to fall asleep and lowering sleep quality.
More exposure to bright natural light (above 2,500 lux) led to earlier bedtimes and stronger daily rhythms.
Women showed more variable activity patterns compared to men.
Frequent nappers had weaker daily rhythms and were less active overall.

A New Perspective on Sleep Health

Lead researcher Daan Van Der Veen emphasized that properly timed light exposure can be a powerful tool for improving sleep and activity levels in older adults. These strategies are not just for those in assisted living but also benefit independent seniors looking to improve their rest naturally.
With populations aging globally, optimizing light exposure could become a key strategy for enhancing overall well-being. By making simple adjustments, older adults can enjoy deeper, more restful sleep—one morning at a time.

Source: Inputs from various media Sources

I’m a pharmacist with a strong background in health sciences. I hold a BSc from Delhi University and a pharmacy degree from PDM University. I write articles and daily health news while interviewing doctors to bring you the latest insights. In my free time, you’ll find me at the gym or lost in a sci-fi novel.