Night Shifts Could Lead to Obesity
We live in a fast paced world that thrives on instant change. Everything needs to be done in a fraction of a second, and speed has become the mantra of the day. The 24x7x365 culture that was once reserved for emergency services such as hospitals, medical stores, police stations and fire stations has now caught on with not-so-emergency services such as food delivery, customer care hotlines, shopping malls, overnight transport systems, etc. While these services may be useful, this “non-stop” availability comes at a price. The people who power these services usually work night shifts, thus, endangering their health. At least that is what current studies say.
Dr. Lap Ah Tse from the Chinese University in Hong Kong has conducted a study that pulled in data from 28 previous studies, involving more than 270,000 people. Dr.Tse says, “Globally, nearly 0.7 billion workers are engaged in a shift work pattern”. These people work in such sectors as hospitals, emergency public services, manufacturing, call centre and transportation. The study found that obesity and being overweight were linked to working in night shifts.
Some of the findings were as follows:
- Night shift workers on duty between 12 am and 5 am showed a collective estimate odds ratio of 1:32. This means that the chances of obesity are 1.32 times higher for those working night shifts, as compared to those in day shifts.
- Permanent night shift workers ran a higher risk of being obese than those in rotational shifts, possibly due to daytime activities in their environment disrupting their sleep. It is quite hard to catch some good sleep during the day, given that the rest of the world around you is active.
- The highest risks were among those who worked 10-hour permanent night shifts or 12-hour rotational shifts,as compared with other night shift workers.
People who worked at night had a significant 23% increased risk of becoming obese. The risk of abdominal obesity was 35% greater, as compared to the normal sample population. Abdominal obesity is the most dangerous type, where fat builds up around the stomach and damages the organs.
What happens is that during night shift the body’s natural ‘clock’, otherwise known as the circadian rhythm, is disturbed. Working at night requires artificial light. Persistent and prolonged exposure to artificial light disturbs this circadian rhythm and results in a reduction of the sleep hormone, melatonin. When melatonin levels are lowered, the body is more susceptible to illness,as melatonin is responsible for balancing other hormones such as cortisol, insulin and leptin, which are necessary forthe healthy functioning of the body’s metabolism. This negative effect on metabolism leads to obesity.
Apart from disturbed sleep and risk of obesity, a side effect of night shifts is poor burning of calories. DrTse’s team found that the sample population burned 12-16% fewer calories than the required minimum, due to reduced metabolic activity. “Modification of working schedules to avoid prolonged exposure to long-term night shifts might be an efficient administrative control to reduce the risk of obesity,”DrTse said.
However, it may sometimes be difficult for people to avoid night shifts. If you or someone you know works night shifts, it is advisable to take extra care to avoid its negative consequences. Consult a physician and get professional help about diet and metabolism to counter the effects of obesity springing from night shifts.
Note: The study of DrTse’s team can be found at [here]