Mad as it may sound, Danish researchers have announced a theory that may not only explain why people all over the world are getting fatter and fatter, but also warn of the serious consequences for life on Earth of continued pollution of the atmosphere by CO2 emissions.
In itself, the theory is quite simple: CO2 contributes to making us fat.
The theory arose several years ago, when Lars-Georg Hersoug studied the development of obesity among people who had been followed over a number of years in the so-called MONICA studies Monitoring of Trends and Determinants in Cardio-vascular Disease in Denmark. These studies have mapped the lifestyles of thousands of Danes.
Hersoug was surprised to see that both fat and thin people taking part in the studies over a 22-year period had put on weight – and the increase was proportionately the same.
Orexins – which are neuropeptide hormones – in the brain stimulate wakefulness and energy expenditure. These hormones may be affected by CO2, and this can cause us to go to bed later, affecting our metabolism so it is easier for us to put on weight. But orexins are also involved in the stimulation of food intake.