Could artificial light make you gain weight?
A study in Tel Aviv earlier this year shows that artificial light at night (ALAN) could not only cause weight gain but could also be a risk factor in certain cancers. The study links artificial light and the production of melatonin with the amount of weight gained. Melatonin is a hormone produced mainly in the brain with the largest amounts being released at night to inform your body that it is time for sleep and is believed to be vital in regulating the body’s circadian rhythms (or body clock). It is then suppressed by sunlight during the daytime. Melatonin is also known as the sleep hormone.
Previous studies have linked melatonin production to brown fat activity. Brown fat has been found to produce a great deal of heat and since it is more abundant in new born babies, it is thought to be nature’s way of preventing the baby from freezing to death. This brown fat is believed to help the body burn more calories than the more harmful white fat and to reduce the risk of insulin resistance. It is thought that as the days became darker our melatonin levels would signal the brown fat to become more active to keep us warm during the cold winter months.
Any artificial light including light from TV, computer games, mobile devices and any other screens will effectively tell your body that the day is much longer than it actually is and will cause the body to significantly reduce its fat-burning rate. Experiments exposing mice to artificial light 24 hours a day put on 50% more weight than those who were exposed to ‘normal’ daylight hours. Recommendations were made to remove all screens from the bedroom so that exposure to the light from the blue and green parts of the spectrum was kept to a minimum.
The latest study from Israel goes one stage further by suggesting that the artificial street lights that shine all night could also be a major factor in our weight gain. The study compared satellite images of the amount of illumination across the globe with the occurrence of people with high BMI according to World Health Organisation (WHO) data. They found that artificial light made a similar contribution to excessive weight gain as eating junk food.
Researchers suggest that their study doesn’t prove that light bulbs themselves cause weight gain as it is likely that the artificial light causes us to eat later in the day when our metabolic rates slow down. They also suggested that whilst urbanisation and higher birth rates were predictors of excess weight, there was still evidence to suggest that the ALAN effect was significant.
The risk factor in developing breast and prostate cancer seems to be due to the reduction in melatonin causing a reduction in antioxidants. These are thought to interact with free radicals and prevent them from causing damage to the body’s cells.
To find out more, please click here to register FREE with simplyweight and you’ll gain access to hundreds of medical weight loss articles, videos, downloads, tools and much more! You can also follow us on Facebook, Twitter, YouTube and Instagram to get useful weight loss updates and boost your motivation level.