1 Letter to the editor Hypoxia a consequence of obesity and also a tool to treat excessive weight loss

We have read with great interest the article by Kong et al [1] about a new strategy to combat obesity and accompanying adverse features, in which normobaric hypoxia training induced more weight loss than normoxia training after 4 weeks on overweight young adults. Such findings complete the view that a modest intermittent hypoxia influence circulating measures of inflammation in healthy humans as reported in a previous issue of Sleep and Breath [2] Indeed, obesity is a growing public health burden affecting affluent societies as well as transition countries [2] with prevalence rates higher than 30 % in many regions. An energy intake higher than the energy expended for basal metabolic rate, physical activity or thermogenic functions is claimed as the explanation for an excessive fat accumulation, where genetics, obesogenic environmental conditions and other factors such as inflammation and oxidative stress could also be involved [3]. Current therapies for obesity treatment and different approaches for body weight management involve dietary interventions based on energy restriction and/or shifts on macronutrient distribution, physical activity programs, pharmacological prescription or surgical procedures. Unfortunately, none of these therapies, either alone or combined, have been able to be fully satisfactory. Therefore, the search for alternative therapies such as the administration of thermogenic agents, satiating compounds, homeorheti