A new study by researchers at the Chinese University of Hong Kong showed that work schedules could play a huge role in the development of obesity.

The study, published in the journal Obesity Reviews, showed that people who were exposed to Night Shift work for a long period of time are more likely to become overweight or obese, compared to other workers in day-shift or regular rotating shifts.

Nocturnal shift disrupts the body’s metabolism

For the study, the researchers conducted a systematic review and meta-analysis of 28 published observational studies that examined the relationships between shift work patterns and obesity.

Participants of these studies were employed in shift works. These include manufacturing employees, healthcare workers, local government staff and truck and bus drivers.

The researchers observed that night shift workers were 29 percent more likely to become overweight or obese. Additionally, long-term exposure to nocturnal schedules was associated with 35 percent higher risk of abdominal obesity.

In a report from Daily Mail, senior author Dr. Lap Ah Tse noted that the increased risk of obesity in night shift workers could be attributed to exposure to artificial light. According to Dr. Tse, being exposed to artificial light at night could disrupt the circadian rhythm, leading to reduced production of the sleep hormone melatonin.

Aside from regulating wake and sleep cycles, melatonin also plays a crucial role in energy metabolism. A 2014 study by researchers at University of São Paulo’s Biomedical Science Institute (ICB-USP) in Brazil showed that melatonin also controls energy expenditure, food intake, energy accumulation in adipose tissue and insulin synthesis and action in cells.

The result of the current study suggests that simple modification in work schedules to prevent long-term exposure to night shifts can help in reducing the risk of obesity.

Obesity remains a big health threat in the United States

Obesity, as defined by the Centers for Disease Control and Prevention, is the weight that is higher than what is considered as the healthy weight for a given height.

Healthcare providers use body mass index, or BMI, as a screening tool for overweight or obesity.

Individuals with 30.0 or higher BMI are considered to be obese. According to a report from the State of Obesity, about one in three adults in the United States were obese. Since the 1980s, obesity rates have doubled among adults.

Around 3.4 million deaths around the world per year can be attributed to obesity or related diseases. Obesity has been linked to the development of several types of cancers, metabolic disorders, and cardiovascular diseases.