Too much light is linked with too much weight

SLEEPING WITH too much light in the room increases the risk of obesity in women, research has shown.

Greater exposure to light at night raised both Body Mass Index (BMI) and waist size in more than 113,000 women taking part in the British study, scientists found.

The Breakthrough Generations Study followed the women for 40 years in an attempt to identify root causes of breast cancer. Obesity is a known risk factor for the disease.

Professor Anthony Swerdlow, from the Institute of Cancer Research in London, said: “Metabolism is affected by cyclical rhythms within the body that relate to sleeping, waking and light exposure.

“The associations we saw in our study between light exposure at night and obesity are very intriguing.

“We cannot yet tell at this stage what the reason for the associations is but the results open up an interesting direction for research.”

The study was funded by the charity Breakthrough Breast Cancer, whose senior research off icer Dr Matthew Lam said: “These findings add weight to previous results from animal studies that looked into how light exposure, circadian rhythms and metabolism could all be connected in some way.

“It’s too early to suggest that sleeping in the dark will help prevent obesity but the association is certainly interesting.”