[Sleep deprivation as a risk factor for obesity]. / La reducción del sueño como factor de riesgo para obesidad.

Nocturnal sleep patterns may be a contributing factor for the epidemic of obesity. Epidemiologic ana experimental studies have reported that sleep restriction is an independent risk factor for weight gain and obesity. Moreover, sleep restriction is significantly associated with incidence and prevalence of obesity and several non-transmissible chronic diseases. Experimental sleep restriction is related to altered plasma leptin and ghrelin concentrations. Both hormones are directly related to appetite and satiety mechanisms. Also, a higher activity of the orexin/hypocretin system has been reported, as well as changes in glucose metabolism and autonomic nervous system. Some studies indicate that these endocrine changes could be associated with a higher diurnal food intake and preference for energy- dense foods. All these changes could result in a positive energy balance, leading to weight gain and a higher obesity risk in the long-term. The present article summarizes the epidemiologic and experimental evidence related to sleep deprivation and higher obesity risk. The possible mechanisms are highlighted.

Sleep alterations and iron deficiency anemia in infancy.

Iron deficiency anemia (IDA) continues to be the most common single nutrient deficiency in the world. An estimated 20-25% of the world's infants have IDA, with at least as many having iron deficiency without anemia. Infants are at particular risk due to rapid growth and limited dietary sources of iron. We found that infants with IDA showed different motor activity patterning in all sleep-waking states and several differences in sleep states organization. Sleep alterations were still apparent years after correction of anemia with iron treatment in the absence of subsequent IDA. We suggest that altered sleep patterns may represent an underlying mechanism that interferes with optimal brain functioning during sleep and wakefulness in former IDA children.

La reducción del sueño como factor de riesgo para obesidad / Sleep deprivation as a risk factor for obesity

Nocturnal sleep patterns may be a contributing factor for the epidemic of obesity. Epidemiologic ana experimental studies have reported that sleep restriction is an independent risk factor for weight gain and obesity. Moreover, sleep restriction is significantly associated with incidence and prevalence of obesity and several non-transmissible chronic diseases. Experimental sleep restriction is related to altered plasma leptin and ghrelin concentrations. Both hormones are directly related to appetite and satiety mechanisms. Also, a higher activity of the orexin/hypocretin system has been reported, as well as changes in glucose metabolism and autonomic nervous system. Some studies indicate that these endocrine changes could be associated with a higher diurnal food intake and preference for energy- dense foods. All these changes could result in a positive energy balance, leading to weight gain and a higher obesity risk in the long-term. The present article summarizes the epidemiologic and experimental evidence related to sleep deprivation and higher obesity risk. The possible mechanisms are highlighted.