Published Feb 11, 2026 | 7:00 AM ⚊ Updated Feb 11, 2026 | 7:00 AM
People working in an office. (iStock)
Synopsis: People with type 2 diabetes spent more time within a healthy blood sugar range when they worked in offices with natural daylight, compared with windowless spaces under constant artificial light, according to a new study. Researchers said the effect may be linked to how daylight helps regulate the body’s circadian rhythm. Doctors stressed that daylight is one factor among many, and that movement, daily routine, medication, diet and exercise remain central.
Natural light at work will not just help lift your mood, it might also help keep your blood sugar steadier.
A recent study published in Cell Metabolism showed that people with type 2 diabetes who spent their workday in an office with natural light had more stable blood sugar levels than when they worked in a windowless office under constant artificial light.
Doctors South First spoke to agree that natural light plays a role in shaping circadian rhythms and, in turn, hormone release. But they noted that the study was conducted on a small group of participants over only a few days, thus the subject needs more research.
Researchers from Maastricht University Medical Center in Netherlands and collaborators ran a randomised crossover study involving 13 adults–eight women and five men–with type 2 diabetes. Each participant spent 4.5 consecutive workdays, from 8 am to 5 pm, in two different office settings.
First, they worked in an office with large windows and ample natural daylight. They then worked in a windowless office with constant artificial lighting. Researchers took blood and muscle samples before, during, and after each lighting condition. Using muscle biopsies, they grew skeletal muscle cells in the lab and examined how the cells’ internal clocks shifted.
They also ran broad laboratory profiling on blood samples to assess metabolites, lipids, and gene transcripts in immune cells.
Continuous glucose monitoring showed no significant difference in average glucose levels between the two conditions. However, participants spent significantly more time within the normal glucose range when working in natural daylight than under artificial light.
A similar “time-in-range” pattern, based on the American Diabetes Association definition, was seen, though it did not reach statistical significance in this small sample.
The study also reported changes pointing to a shift in metabolism under daylight exposure, including reduced carbohydrate oxidation and increased fat oxidation during waking hours, along with higher evening melatonin levels.
“We found signs that daylight exposure may help the body burn more fat and a bit less carbohydrate during waking hours, and it was linked with higher evening melatonin, a hormone tied to the body clock and sleep,” the study said.
The human body runs on an internal “clock”, known as the circadian rhythm, doctors told South First. Daylight, or natural light, is a key cue that helps synchronise this clock. The internal clock controls sleep–wake patterns and influences metabolic processes.
The study’s authors also note that modern indoor life often reduces daylight exposure, which may disrupt circadian rhythms and contribute to metabolic disease.
“The study is on a very small sample and the findings are not really striking. It has been proposed earlier that natural light is better, and that artificial light, especially exposure to blue light from mobile phones, disrupts the circadian rhythm. This, in turn, changes hormones and disrupts metabolic health. But no proper study has been done on this,” Dr V Mohan, Chairman of Dr Mohan’s Diabetes Specialities Centre, told South First.
Describing the research as fairly well conducted, Dr Mohan said it showed some minor changes but could not explain all cases of uncontrolled diabetes. Daylight exposure, he added, may be one contributing factor.
Outdoor activity, he explained, usually involves walking and natural light exposure, and may also increase oxygen intake. Indoors, people tend to be more sedentary, allowing such confounding factors to add up.
Taken together, he said, the findings are of interest and point to the value of “going back to the basics, the way our ancestors lived, which is better for health”.
Both Dr Mohan and the study’s researchers warned that this is not proof that sunlight alone can “treat” diabetes. Doctors said that getting more daytime natural light—by sitting near a window, taking daylight breaks, or walking in the morning—while continuing medication, diet, and exercise, can help set the circadian rhythm and, in turn, support metabolic health.
If office spaces have fewer windows, employers can create a simple seating roster so everyone gets at least two to three days closer to windows.
Doctors also suggest encouraging people to take a 10-minute break or a short walk around the compound to get daylight exposure.
Keeping blinds open in the morning helps.
If there are no windows, it is better to switch from tube lights to LED lighting. Use daylight white bulbs in the morning, especially in darker zones, and shift to warm white lighting in the evening if teams are working late. Doctors advise avoiding harsh, bright blue light after 6–7 pm.
(Edited by Dese Gowda)
