It’s well accepted that reduced physical activity and fast food are linked to obesity. But the evidence that these are the main causes of obesity is largely circumstantial. To stimulate debate, experts suggest 10 other possible causes of obesity, outlined in the International Journal of Obesity.
1. Sleep debt. Getting too little sleep can increase body weight. Today, many get less shut-eye than ever.
2. Pollution. Hormones control body weight. And many of today’s pollutants affect our hormones.
3. Air conditioning. You have to burn calories if your environment is too hot or too cold for comfort. But more people than ever live and work in temperature-controlled homes and offices.
4. Decreased smoking. Smoking reduces weight. People smoke much less than they used to.
5. Medicine. Many different drugs including contraceptives, steroid hormones, diabetes drugs, some antidepressants, and blood pressure drugs can cause weight gain. Use of these drugs is on the upswing.
6. Population age, ethnicity. Middle-aged people and Hispanic-Americans tend to be more obese than young European-Americans. Americans are getting...