Genes, lack of sleep, even air conditioning – all sorts of unlikely things can influence your weight.
Lack of sleep
People who sleep for four hours or less per night are 73 per cent more likely to be obese. A team from the Mailman School of Public Health at Columbia University in New York found that, even after factors such as depression, physical activity, alcohol consumption, ethnicity, education, age and gender had been taken into account, people were more likely to be obese the less sleep they had.
Those who got only five hours' sleep were 50 per cent more likely to be obese than those who were getting a full night's rest, and those who slept for just six hours were 23 per cent more likely to be substantially overweight. Dr Stephen Heymsfield, who worked on the study, said it was not as simple as saying that if people were awake for longer, they were likely to eat more. "There's growing scientific evidence that there's a link between sleep and the various neural pathways that regulate food intake." Previous research has shown that sleep deprivation is linked to a decrease in levels of leptin (see Hormones). Levels of the hormone grehlin, which makes people want to eat, have also been seen to increase in people who are sleep-deprived.
Too much choice
Although a varied diet is likely to be rich in nutrients, US scientists found that the availability of lots of different foods can also encourage overeating. Hollie Raynor and Dr Leonard Epstein from the University of Buffalo said that variety decreased the feeling of satisfaction, making people more vulnerable to obesity. "Both people and animals will eat more food when a meal or diet contains a greater variety of food, which can eventually cause weight gain," they said. The research showed that meals composed of foods of a similar shape, taste and colour may curb overeating.
Source - Independent