Feasibility of using infrared thermal imaging to examine brown adipose tissue in infants aged 18 to 25 months

Background Recent studies in adults indicate that cold-induced temperature change of supraclavicular skin corresponds with brown adipose tissue (BAT) thermogenesis. Aim This study examined the feasibility of using thermography to assess temperature changes in infants aged 18–25 months after mild cooling. Further, this study sought to evaluate whether cold exposure induces a thermal response suggestive of BAT activity underlying the supraclavicular region. Subjects and Methods Changes in maximum skin temperature at the supraclavicular and interscapular regions were determined using thermal imaging following a mild 5-minute cooling condition (by removal of clothes in a climate-controlled room) in 67 Samoan infants. Temperature changes of the forehead and hand, known BAT-free regions, served as indicators of cooling efficacy. Results Infants with increased hand and forehead temperatures after cold exposure were excluded from analysis, reducing the effective sample size to 19 infants. On average, forehead (p < 0.001), hand (p < 0.001) and back (0.029) temperatures dropped significantly while supraclavicular temperatures remained constant. Participants with greater decreases in forehead temperature tended to exhibit greater supraclavicular thermogenesis (p = 0.084), suggesting potential BAT activity in this region. Conclusions While further work is necessary to develop a reliable cooling condition, this study provides proof-of-concept for non-invasive assessment of BAT activity in infants

Effect of maternal nutrient intake during 31–37 weeks gestation on offspring body composition in Samoa

Background Pregnancy dietary intake may be associated with newborn body composition, a predictor of future obesity. In Samoa, an energy-dense diet contributes to an alarming prevalence of adult obesity. Identifying associations between pregnancy nutrition and infant body composition in this setting may guide strategies to mitigate intergenerational transmission of obesity risk. Aim To examine dietary macro- and micronutrient intake of Samoan women during the third trimester of pregnancy and associations with infant body composition. Subjects and methods At 34–41 weeks of gestation, we measured dietary intake from the prior month using a Food Frequency Questionnaire (FFQ). Dual-energy X-ray absorptiometry (DXA) measured infant body composition at 1–14 days. We used multivariable linear regression models accounting for confounders to identify independent effects of nutrient intake on infant body composition. Results After adjusting for maternal body mass index, age, gravidity, infant age, and sex, a respective 0.2 g increase and 0.2 g decrease in infant bone mass was associated with fibre and saturated fat intake. Increased protein intake was associated with 0.02 g decrease in bone mass. Conclusions While maternal dietary intake was not associated with infant adiposity or lean mass, we observed an effect on bone mass whose role in regulating metabolic health is overlooked