A U.S. study shows that young women who spend too much time online, lack sleep, or drink alcohol frequently are more likely to gain weight than their peers.
Researchers from Harvard Medical School and Brigham and Women's Hospital, its affiliated hospital, tracked 5,036 females aged 14 to 21 for a year. The study included their weekly leisure internet time, daily sleep duration, and weekly alcohol consumption.
The survey found that the longer the time spent online, the higher their Body Mass Index (BMI), a measure of weight relative to height. This effect was particularly pronounced in women under 18. Women who slept for no more than 5 hours a day were more prone to weight gain than those who got the standard 8 hours of sleep. Women who drank more than two alcoholic beverages a week gained more weight than those who drank less than two. Among these factors, insufficient sleep had a greater impact on BMI than excessive internet use.
The researchers pointed out that internet use can cut into exercise time, leading to weight gain. Lack of sleep may cause people to be too tired to exercise during the day and can also affect the body's hormone secretion and metabolism, making it easier to gain weight. Alcohol, on the other hand, is high in calories, and people who drink often do not control their food intake to compensate for the extra calories.
As an example, the researchers cited a 19-year-old woman of average height and weight. If she engaged in these "high-risk" activities, she could gain about 1.8 kilograms in a year. While this might seem insignificant at first, the accumulated weight gain over time becomes considerable.
The findings of this research were published in the journal Pediatrics.