No, this is not 1 April – and this is not an April Fool’s hoax.
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.
“There’s something in the air”
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.
“The normal theory is that fat people get fatter because they don’t move as much as they should,” says Hersoug, now a post-doc at the Research Centre for Prevention and Health at Glostrup University Hospital. “But the study showed that thin people also get fatter, and this happened over the whole of the 22-year period of the study.”
Obesity may follow CO2 concentration
Hersoug has since studied events and research results that could support his theory.
1. He says the development in obesity in the US was fastest in the period 1986-2010 on the east coast – where CO2 concentrations are highest.
2. A study from 2010, covering 20,000 animals in various laboratories, showed that all the animals put on weight, even though they were given food under controlled conditions and should therefore not have put on weight. The animals studied included dogs, cats, mice and monkeys. And when researchers studied rats in both urban and rural environments in the US, the result was the same.