Health Sachet No 305:

The artificial light that we use at night, especially from our screens of TV, mobiles and computers, may be contributing to obesity, cancer, diabetes, and heart disease.

The household lights at night suppress the production of Melatonin, a hormone that affects our circadian rhythm.

As a result, our biological clock goes for a toss, possibly causing higher blood sugar, leading to pre-diabetes, and lower leptin (a hormone that makes you feel full), leading to overeating and obesity.

These lights also cause short sleep, which is linked to depression, diabetes, and heart disease.

The bigger culprit amongst all the colours of light is the blue one. The bluish lights increase attention, reaction time, and mood – a boon in the daytime but a bane for sleeping at night.

The light from older bulbs was more orangish and less blue. The newer LED lamps and screens are predominantly bluish, which shift circadian rhythms twice as much (by 3 hours).

• Avoid looking at bright screens at least 2 hours before bedtime.

• Get exposure to a lot of daylight which will boost the ability to sleep well at night.