Think you can lose a few pounds by simply changing your diet? This is possible, but not necessarily sufficient. In fact, other factors that are completely external and whose health effects we are far from suspecting intervene in the regulation of weight. In recent years, researchers have realized that while some people gain weight because they eat too much or in an unbalanced way, diet does not explain all weight gain.

Here is a hypothesis of five key points that can accentuate weight gain or prevent weight loss.

1st key: too short nights and lack of sleep.

Numerous studies suggest that lack of sleep promotes weight gain and even obesity. By observing the sleep time of people with various chronic diseases, the researchers found that these people sleep less than 7 hours per night and are therefore 3 times more likely to be obese. This can be explained on the one hand, because lack of sleep increases the level of ghrelin, a hormone that stimulates appetite, while decreasing the level of leptin. Ghrelin levels increase before meals and decrease after meals. It is considered to be the antagonist of leptin, another hormone produced by the adipocytes and whose increase induces the feeling of satiety. Ghrelin is mainly secreted by the cells of the stomach and secondarily by some cells of the pancreas.

It also seems that the waking time is more conducive to the desire to eat, obviously when we sleep we do not eat!

And the researchers conclude: all adults should sleep at least 8 hours per night to maintain their body weight. This principle is also applicable to younger children. This was corroborated by a New Zealand study (2008) which found that children who slept less than 9 hours per night were three times more likely to be obese. Similarly, children who don't get enough sleep are more likely to be hyperactive. School-age children should have 10 to 11 hour nights and younger children should have 11 to 13 hour nights for good health.

2nd: various toxins and pollution.

Even if it doesn't seem directly related, there is a connection between chemical pollutants and weight gain. Studies published since 2002 increasingly suggest that pollution may contribute to the growth of obesity in our "civilized" countries. Indeed, the number of chemical substances to which we are exposed would cause a disruption of our entire hormonal system and more specifically would disturb the weight balance. Some molecules seem to be particularly involved because of the hormone-like action they would exert, and this, more precisely, in relation to the sexual hormones. Researchers suspect that certain molecules modify the development processes of fatty tissue and increase the risk of obesity. Phthalates and Bisphenol A, used in food packaging, were singled out by American researchers in 2007. According to these researchers, even in utero exposure could induce obesity risks in future babies.