Circadian rhythms regulate metabolic processes, including glucose metabolism and insulin sensitivity. Disruptions in circadian rhythms can lead to metabolic impairments, increasing the risk of obesity, type 2 diabetes, and metabolic syndrome. A recent study found that personal light exposure patterns predict the risk of developing type 2 diabetes.

Researchers assessed the light exposure patterns of more than 84,000 UK Biobank participants. Participants wore light sensors for one week to record their day and night light exposure. The researchers tracked the incidence of type 2 diabetes among the participants over an average follow-up period of nearly eight years.

They found that diabetes risk increased as night light exposure increased. Compared to low light exposure, the risk of diabetes increased by - 29 percent with moderate light exposure. - 39 percent with high-moderate light exposure. - 53 percent with high light exposure. The increased risk associated with night light exposure was comparable to the difference between people with low and moderate genetic risk for diabetes.

These findings suggest that nighttime light exposure is a risk factor for developing type 2 diabetes, comparable to genetic risk factors. Interestingly, low solar angle light – as in the early morning or late evening – resets the body’s circadian rhythms, improving metabolic health and mood. Learn more about low solar angle light exposure in this episode featuring Dr. Andrew Huberman.