According to a small new study, exposure to blue light before and during your evening meal may affect how much you want to eat. Compared to exposure to dim light, exposure to blue light spurred higher hunger levels, starting 15 minutes after light exposure and those hunger levels stayed higher for about two hours after the final bite.
“These results are important because they suggest that manipulating environmental light exposure for humans may represent a novel approach of influencing food intake patterns and metabolism,” commented study co-author Ivy Cheung, a doctoral candidate in the Interdepartmental Neuroscience program at Northwestern University in Chicago, Illinois.
During the study, 10 healthy adults, were exposed to dim lighting for two days in individual bedrooms in a hospital setting. On day three, the participants were exposed to blue-enriched light from light boxes, while doing seated activities like reading and during their evening meal. The participants rated their hunger stronger after blue-light exposure, Cheung says.
Other studies have also shown that this blue light affects our sleeping patterns too. “And in our constantly connected society, we’re probably getting more blue light exposure than we realise. Skimping on sleep has also been shown to increase hunger and calorie intake,” said Cheung.