Core body temperature is lower in postmenopausal women than premenopausal women: potential implications for energy metabolism and midlife weight gain.

OBJECTIVE: Weight gain during the menopausal transition is common. Although studies have suggested that weight gain is more likely related to aging than menopause, there is a reduction in resting energy expenditure with surgical or natural menopause which is independent of age and changes in body composition. The underlying mechanisms could include a reduction in core body temperature. METHODS: Data were obtained from two related studies. Sample size was 23 men and 25 women (12 premenopausal,13 postmenopausal). In the Clinical Research Unit, core temperature was measured every minute for 24 hours (CorTemp System,HQ Inc.). RESULTS: Mean 24-hour core body temperature was 0.25 ± 0.06 °C lower in postmenopausal than premenopausal women (p=0.001). Mean 24-hour core temperature was 0.34 ± 0.05 °C lower in men than in premenopausal women (p<0.001). CONCLUSIONS: Postmenopausal women, like men, had lower core body temperatures than premenopausal women. This may have implications for midlife weight gain.

An obesity educational intervention for medical students addressing weight bias and communication skills using standardized patients.

BACKGROUND: In order to manage the increasing worldwide problem of obesity, medical students will need to acquire the knowledge and skills necessary to assess and counsel patients with obesity. Few educational intervention studies have been conducted with medical students addressing stigma and communication skills with patients who are overweight or obese. The purpose of this study was to evaluate changes in students' attitudes and beliefs about obesity, and their confidence in communication skills after a structured educational intervention that included a clinical encounter with an overweight standardized patient (SP). METHODS: First year medical students (n = 127, 47% female) enrolled in a communications unit were instructed to discuss the SPs' overweight status and probe about their perceptions of being overweight during an 8 minute encounter. Prior to the session, students were asked to read two articles on communication and stigma as background information. Reflections on the readings and their performance with the SP were conducted prior to and after the encounter when students met in small groups. A newly constructed 16 item questionnaire was completed before, immediately after and one year after the session. Scale analysis was performed based on a priori classification of item intent. RESULTS: Three scales emerged from the questionnaire: negative obesity stereotyping (7 items), empathy (3 items), and counseling confidence (3 items). There were small but significant immediate post-intervention improvements in stereotyping (p = .002) and empathy (p < .0001) and a very large mean improvement in confidence (p < .0001). Significant improvement between baseline and immediate follow-up responses were maintained for empathy and counseling at one year after the encounter but stereotyping reverted to the baseline mean. Percent of students with improved scale scores immediately and at one year follow up were as follows: stereotyping 53.1% and 57.8%; empathy 48.4% and 47.7%; and confidence 86.7% and 85.9%. CONCLUSIONS: A structured encounter with an overweight SP was associated with a significant short-term decrease in negative stereotyping, and longer-term increase in empathy and raised confidence among first year medical students toward persons who are obese. The encounter was most effective for increasing confidence in counseling skills.

Maternal leptin predicts adiposity of the neonate.

BACKGROUND: Increased adiposity at birth may identify infants at high risk of developing obesity. Maternal obesity and hyperglycemia in pregnancy are associated with increased neonatal adiposity; however, features of maternal obesity that contribute to increased neonatal adiposity need further study. AIMS: To measure adiposity in neonates of obese and normal-weight women without gestational diabetes to test the hypothesis that obese women have neonates with increased adiposity compared to neonates of normal-weight women. METHODS: Sixty-one pregnant women, with a normal or obese BMI, and their neonates participated in this cross-sectional study at an academic medical center. Neonatal adiposity, expressed as percent body fat (fat mass/body mass), was measured by air displacement plethysmography and cord blood was assayed for biomarkers. RESULTS: Adiposity in neonates of obese and normal-weight mothers did not differ. Stratifying mothers by leptin level showed that neonates born to mothers with higher leptin had significantly higher adiposity (13.2 vs. 11.1%, p = 0.035). In the entire cohort, adiposity positively correlated with cord blood leptin (r = 0.48, p < 0.001) and adiponectin (r = 0.27, p = 0.04) levels. CONCLUSION: Obesity in normoglycemic pregnant women was not associated with increased neonatal adiposity. High maternal leptin levels identified neonates with increased adiposity.

Maternal obesity and vitamin D sufficiency are associated with cord blood vitamin D insufficiency.

CONTEXT: An inverse relationship between total serum 25-hydroxyvitamin D (25-OH D) and increased adiposity has been established in children, adolescents, and adults. However, the relationship between neonatal adiposity and vitamin D status has not been reported. Both maternal obesity and vitamin D deficiency in pregnancy are common and are associated with adverse pregnancy outcomes. OBJECTIVE: The aim of the study was to determine the relationship between vitamin D levels in mothers and newborns, as influenced by maternal obesity, and evaluate these associations with neonatal adiposity. DESIGN, SETTING, AND PATIENTS: Sixty-one maternal-neonatal pairs participated in this cross-sectional study at an academic medical center. Mothers had a prepregnancy body mass index that was normal or obese. OUTCOME MEASURES: Maternal and cord blood sera were assayed for 25-OH D, and neonatal body composition was measured by air displacement plethysmography. RESULTS: Mothers had similar and sufficient levels of 25-OH D when measured at 36-38 wk gestation, irrespective of body mass index category (normal weight, 46.05, vs. obese, 49.84 ng/ml; P = not significant). However, cord blood 25-OH D was higher in neonates of normal-weight mothers compared to neonates of obese mothers (27.45 vs. 20.81 ng/ml; P = 0.02). The variance in cord blood 25-OH D was explained by four factors: maternal 25-OH D level, the presence of maternal obesity, maternal age, and neonatal adiposity (r(2) = 0.66). CONCLUSION: Obese women transfer less 25-OH D to offspring than normal-weight women, despite similar serum levels. Cord blood 25-OH D levels directly correlate to neonatal percentage body fat. These novel findings underscore the evolving relationships between maternal obesity, vitamin D nutritional status, and adiposity in the neonatal period that may influence subsequent childhood and adulthood vitamin D-dependent processes.

24-h core temperature in obese and lean men and women.

Maintenance of core temperature is a major component of 24-h energy expenditure, and its dysregulation could contribute to the pathophysiology of obesity. The relationship among temperature, sex, and BMI, however, has not been fully elucidated in humans. This study investigated core temperature in obese and lean individuals at rest, during 20-min exercise, during sleep, and after food consumption. Twelve lean (18.5-24.9 kg/m(2)) and twelve obese (30.0-39.9 kg/m(2)) healthy participants, ages 25-40 years old, were admitted overnight in a clinical research unit. Females were measured in the follicular menstrual phase. Core temperature was measured every minute for 24 h using the CorTemp system, a pill-sized sensor that measures core temperature while in the gastrointestinal tract and delivers the measurement via a radio signal to an external recorder. Core temperature did not differ significantly between the obese and lean individuals at rest, postmeals, during exercise, or during sleep (P > 0.5), but core temperature averaged over the entire study was significantly higher (0.1-0.2 °C) in the obese (P = 0.023). Each individual's temperature varied considerably during the study, but at all times, and across the entire study, women were ~0.4 °C warmer than men (P < 0.0001). These data indicate that obesity is not associated with a lower core temperature but that women have a higher core temperature than men at rest, during sleep, during exercise, and after meals.