It will seem strange, but among the countless benefits that - in the case of overweight - slimming brings with it, there is also a danger to health. Several studies have shown that body weight loss, after a low-calorie diet or bariatric surgery, leads to increased plasma concentrations of toxic substances.
Many environmental pollutants - for example dioxin, DDT and its degradation products, hexachlorobenzene, polychlorinated biphenyls and various other persistent organic pollutants (POPs) - are lipophilic molecules ; means that they are related to lipids (fats) and able to dissolve in them.
Once introduced into the human body these substances are metabolized with extreme difficulty (the hepatic metabolism of xenobiotics tends to increase their water solubility in order to allow their urinary elimination, but unfortunately the liver does not have effective enzymes for the elimination of POPs). Consequently, pollutants tend to accumulate, depositing themselves preferentially in adipose tissue . Therefore, when there is a loss of weight, together with the fatty acids stored in the adipose tissue in the form of triglycerides, the amount of pollutants stored in the adipocytes is also released.
The speech can also be seen in reverse, in the sense that one of the negative effects of obesity is to increase the deposit of persistent organic pollutants in the body. Although the abundance of adipose tissue is protective in the event of acute intoxication with POPs, at the same time, by preserving substances in the body for a long time, it contributes to increasing chronic toxicity. Not surprisingly, recent studies suggest that these pollutants are related to the metabolic dysfunctions associated with obesity, activating an inflammatory phenotype in adipose tissue. Therefore, more than an excuse to avoid losing weight, the question should be understood as an additional reason not to put on weight .
There is then another side of the coin, the one for which it would be the same exposure to persistent organic pollutants to favor obesity. This effect, called obesogenic, would be significant during particular phases of life, which are those of development (from the pre-natal period until the end of puberty); although an epigenetic effect of these pollutants is assumed, the relative mechanism of obesogenic action has not yet been clarified.
