Having a little extra light in your bedroom can be helpful if you want to read before falling asleep, but it may also increase your likelihood of gaining weight.
According to a study by the Institute of Cancer Research in London, there is a significant link between obesity and bedroom brightness. Researchers noticed that individuals who slept in well-lit bedrooms had a higher likelihood of gaining weight.
“In this very large group of people there is an association between reported light exposure at night and overweight and obesity,” the authors wrote.
Light Weight
To better understand the correlation between light exposure in a person’s sleeping quarters and obesity, researchers asked over 100,000 women to rate the light in their bedroom as one of the four following options.
- Light enough to read
- Light enough to see across the room, but not read
- Light enough to see your hand in front of you, but not across the room
- Too dark to see your hand or you wear a mask
Researchers also collected physical indicators for each respondent, including BMI, waist-to-hip ratio, and waist circumference. They found that respondents who slept with more light in their room were more likely to have larger waistlines and higher BMIs. Despite the compelling findings, researchers say there isn’t enough evidence to conclusively say that making your room darker will make a difference in your weight, and further investigations into the matter are needed.
“There might be other explanations for the association, but the findings are intriguing enough to warrant further scientific investigation,” the authors concluded.
Dr. Silverman comments
One of the pitfalls of lack of sleep is the propensity to gain weight. Although it isn’t directly stated in the study, it’s possible to assume that people with more light in their bedroom get less sleep than those in darker conditions. If you’re awake longer than others, two things occur:
- You have more time to snack throughout the day or eat before bed; and
- Hormone imbalance – Your lack of sleep slows your body’s production of leptin, a hormone that signals the brain that you’ve had enough food. Lack of sleep has also been shown to lead to an increase in ghrelin, a hormone that stimulates a person’s appetite. As you can see, when leptin and ghrelin get out of sync, a person can feel hungry more often and have an increased likelihood to gain weight.
Keep the bedroom dark, and avoid falling asleep with the TV on. You’ll fall asleep faster and stay asleep longer.
Related source: Health News One