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Summary In May 2020, Latin America became the epicenter of the COVID‐19 pandemic, a region already afflicted by social disparities, poor healthcare access, inadequate nutrition and a large prevalence of noncommunicable chronic diseases. Obesity and its comorbidities are increasingly prevalent in Latin America, with a more rapid growth in individuals with lower income, and currently a disease associated with COVID‐19 severity, complications and death. In this document, the Latin American Association of Obesity Societies and collaborators present a review of the burden of two pandemics in Latin America, discuss possible mechanisms that explain their relationship with each other and provide public health and individual recommendations, as well as questions for future studies.

Melatonin, a pineal hormone synthesized at night, is critical for the synchronization of circadian and seasonal rhythms, being a key regulator of energy metabolism in many animal species. Although studies in humans are lacking, several reports, mainly on hibernating animals, demonstrated that melatonin supplementation and a short photoperiod increase brown adipose tissue (BAT) mass. The present proof-of-concept study is the first, to our knowledge, to evaluate BAT in patients with melatonin deficiency (radiotherapy or surgical removal of pineal gland) before and after daily melatonin (3 mg) replacement for 3 months. All four studied patients presented increased BAT volume and activity measured by positron emission tomography-MRI. We also found an improvement in total cholesterol and triglyceride blood levels without significant effects on body weight, liver fat, and HDL and LDL levels. Albeit not statistically significant, fasting insulin levels and HOMA of insulin resistance decreased in all four patients. The present results show that oral melatonin replacement increases BAT volume and activity and improves blood lipid levels in patients with melatonin deficiency, suggesting that melatonin is a possible BAT activator. Future studies are warranted because hypomelatoninemia is usually present in aging and appears as a result of light-at-night exposure and/or the use of b-blocker drugs.Melatonin, a pineal hormone synthesized and released at night that plays a critical role in the synchronization of circadian and seasonal rhythms, has been studied as a key regulator of energy metabolism in many animal species for a long time (1,2). Pinealectomized rats show increased body weight gain and metabolic disturbances that are prevented by daily melatonin supplementation at night, without decreasing energy intake (1-5). This suggests that melatonin also regulates energy metabolism by its action on energy expenditure, possibly as related to the activation of brown adipose tissue (

Few studies on combination therapies for the treatment of obesity had been conducted until recently, when two fixed-dose combinations, bupropion-naltrexone ER fixed-dose combination and phentermine-topiramate ER titrated-dose combinations were evaluated in clinical studies that ultimately led to FDA approval. Areas covered: In this review, we discuss safety concerns about both combinations, the rationale and history of combination therapies for obesity (including phentermine plus fenfluramine), and possible future new combinations. Expert opinion: Combination therapies are a promising new area in obesity treatment, similar to what occurs with diabetes and hypertension. Safety assessment is highly important due to the high number of potential users on a chronic basis.

Brown adipose tissue, an essential organ for thermoregulation in small and hibernating mammals due to its mitochondrial uncoupling capacity, was until recently considered to be present in humans only in newborns. The identification of brown adipose tissue in adult humans since the development and use of positron emission tomography marked with 18-fluorodeoxyglucose (PET-FDG) has raised a series of doubts and questions about its real importance in our metabolism. In this review, we will discuss what we have learnt since its identification in humans as well as both new and old concepts, some of which have been marginalized for decades, such as diet-induced thermogenesis. Arq Bras Endocrinol Metab. 2014;58(9):889-99 Keywords Brown adipose tissue; obesity; thermogenesis; UCP-1; energy expenditure RESUMO O tecido adiposo marrom, órgão essencial para a termorregulação de animais hibernantes e pequenos devido à sua capacidade desacopladora, era até poucos anos considerado presente apenas em recém-nascidos na espécie humana. A identificação do tecido adiposo marrom em adultos com o desenvolvimento e uso da tomografia de emissão de pósitron marcado com 18-fluorodesoxiglicose (PET-FDG) gerou questões sobre sua real importância para nosso metabolismo. Nesta revisão, discutiremos o que aprendemos nesse tempo, assim como conceitos antigos e novos, alguns marginalizados por décadas, como a termogênese induzida por dieta. Arq Bras Endocrinol Metab. 2014;58(9):889-99 Descritores