Stress reduction through contact with nature is well established, but far less is known about the contribution of contact parameters – duration, frequency, and nature quality. This study describes the relationship between duration of a nature experience (NE), and changes in two physiological biomarkers of stress – salivary cortisol and alpha-amylase. It is the first study to employ long-term, repeated-measure assessment and the first evaluation wherein study participants are free to choose the time of day, duration, and the place of a NE in response to personal preference and changing daily schedules. During an 8-week study period, 36 urban dwellers were asked to have a NE, defined as spending time in an outdoor place that brings a sense of contact with nature, at least three times a week for a duration of 10 min or more. Their goal was compliance within the context of unpredictable opportunity for taking a nature pill. Participants provided saliva samples before and after a NE at four points over the study period. Before-NE samples established the diurnal trajectory of each stress indicator and these were in line with published outcomes of more closely controlled experiments. For salivary cortisol, an NE produced a 21.3%/hour drop beyond that of the hormone’s 11.7% diurnal drop. The efficiency of a nature pill per time expended was greatest between 20 and 30 min, after which benefits continued to accrue, but at a reduced rate. For salivary alpha-amylase, there was a 28.1%/h drop after adjusting for its diurnal rise of 3.5%/h, but only for participants that were least active sitting or sitting with some walking. Activity type did not influence cortisol response. The methods for this adaptive management study of nature-based restoration break new ground in addressing some complexities of measuring an effective nature dose in the context of normal daily life, while bypassing the limitations of a clinical pharmacology dose–response study. The results provide a validated starting point for healthcare practitioners prescribing a nature pill to those in their care. This line of inquiry is timely in light of expanding urbanization and rising healthcare costs.

BackgroundMaternal depression may influence feeding practices important in determining child eating behaviors and weight. However, the association between maternal depressive symptoms and feeding practices has been inconsistent, and most prior studies used self-report questionnaires alone to characterize feeding. The purpose of this study was to identify feeding practices associated with maternal depressive symptoms using multiple methodologies, and to test the hypothesis that maternal depressive symptoms are associated with less responsive feeding practices.MethodsIn this cross-sectional, observational study, participants (n = 295) included low-income mothers and their 4- to 8-year-old children. Maternal feeding practices were assessed via interviewer-administered questionnaires, semi-structured narrative interviews, and videotaped observations in home and laboratory settings. Maternal depressive symptoms were measured using the Center for Epidemiologic Studies-Depression scale (CES-D). Regression analyses examined associations between elevated depressive symptoms (CES-D score ≥16) and measures of maternal feeding practices, adjusting for: child sex, food fussiness, number of older siblings; and maternal age, body mass index (BMI), education, race/ethnicity, single parent status, perceived child weight, and concern about child weight.ResultsThirty-one percent of mothers reported depressive symptoms above the screening cutoff. Mothers with elevated depressive symptoms reported more pressuring of children to eat (β = 0.29; 95% Confidence Interval (CI): 0.03, 0.54) and more overall demandingness (β = 0.16; 95% CI: 0.03, 0.29), and expressed lower authority in child feeding during semi-structured narrative interview (Odds Ratio (OR) for low authority: 2.82; 95% CI: 1.55, 5.12). In homes of mothers with elevated depressive symptoms, the television was more likely audible during meals (OR: 1.91; 95% CI: 1.05, 3.48) and mothers were less likely to eat with children (OR: 0.48; 95% CI: 0.27, 0.85). There were no associations between maternal depressive symptoms and encouragement or discouragement of food in laboratory eating interactions.ConclusionsMothers with elevated depressive symptoms demonstrated less responsive feeding practices than mothers with lower levels of depressive symptoms. These results suggest that screening for maternal depressive symptoms may be useful when counseling on healthy child feeding practices. Given inconsistencies across methodologies, future research should include multiple methods of characterizing feeding practices and direct comparisons of different methodologies.

Despite increased attention to the role of temperament in children’s obesogenic eating behaviors, there is a paucity of research examining whether different dimensions of temperament may be differentially associated with specific eating behaviors among preschool-age children. The purpose of the current study was to examine whether three temperament dimensions (surgency, negative affectivity, and effortful control) were uniquely associated with six obesogenic eating behaviors (caregiver-reported food responsiveness, enjoyment of food, emotional overeating, satiety responsiveness, and tantrums over food; and observed eating in the absence of hunger) among low-income preschool-age children, covarying home environment quality. Results showed that temperament dimensions were differentially associated with different eating behaviors. Specifically, preschoolers with higher surgency were more likely to overeat in response to external cues, have frequent desire to eat, derive pleasure from food, and eat in the absence of hunger. In contrast, preschoolers with higher negative affectivity were more likely to have tantrums over being denied food and less likely to eat in the absence of hunger. Effortful control was not uniquely associated with obesogenic eating behavior. Findings remained significant even when home chaos was accounted for, suggesting that child surgency and negative affectivity are important to consider, independent of home environment. Results are discussed with regard to theoretical implications for the study of childhood obesity and for applied prevention implications.

Short sleep duration is associated with increased obesity, however, the role of sleep timing is understudied, particularly in young children. Objective To test the independent main and moderating effects of sleep timing on body mass index (BMI) in low-income preschool-aged children (M=4.11 years, SD=0.54). Methods Parents reported demographics and children’s sleep concurrently, and a subset of children was followed longitudinally. Child height and weight were measured and BMI z-score (BMIz) calculated. Regression analysis evaluated main effects of sleep timing (bedtime, weekday-to-weekend schedule shifting, napping) on concurrent BMIz and future rate of change, and their moderating effects on the sleep duration-BMIz association. Results Of 366 children (longitudinal subsample=273), 50% were male, 57% white, and 37% overweight or obese. Nocturnal sleep duration predicted concurrent BMIz, but not rate of change in BMIz over time. Bedtime was a moderator; the sleep duration-BMIz association was present only among children with bedtimes after 9pm (−0.44; 95% CI −0.69, −0.18). Schedule shifting was a moderator; the association between greater nocturnal sleep duration and lesser rate of future BMIz increase was present only among children with the most consistent sleep schedules (<45 minute delay in weekend bedtime: β = −0.12; 95% CI −0.23, −0.01). Daytime napping did not moderate the nocturnal sleep duration-BMIz association. Covariates (sleep-disordered breathing; soda consumption; home chaos) did not explain these associations. Conclusions Among low-income preschoolers, sleep timing moderated the nocturnal sleep duration-BMIz association. Understanding how sleep timing, as well as sleep duration, relates to childhood obesity is important for prevention efforts.

Context:The role of the extracellular matrix (ECM) in regulating adipocyte metabolism in the context of metabolic disease is poorly defined.Objective:The objective of this study was to define the metabolic phenotype of adipocytes associated with human diabetes (DM) and the role of the ECM in regulating adipocyte metabolism.Design:Adipose tissues from obese patients were studied in standard 2-dimensional (2D) cell culture and an in vitro model of decellularized adipose tissue ECM repopulated with human adipocytes, and results were correlated with DM status.Setting:This study was conducted at the Academic University Medical Center and Veteran’s Administration Hospital.Patients:Seventy patients with morbid obesity undergoing bariatric surgery were included in the study.Interventions:Visceral and subcutaneous adipose tissues were collected at the time of bariatric surgery.Outcome measures:This study used metabolic assays for glucose uptake, lipolysis, and lipogenesis in adipocytes in 2D cell culture and 3-dimensional ECM culture.Results:Adipocytes from subjects with DM manifest decreased glucose uptake and decreased lipolysis in 2D culture. ECM supports differentiation of mature adipocytes and recapitulates DM-specific differences in adipocyte metabolism observed in 2D culture. ECM from subjects without DM partially rescues glucose uptake and lipolytic defects in adipocytes from subjects with DM, whereas ECM from subjects with DM impairs glucose uptake in adipocytes from subjects without DM.Conclusions:DM is associated with adipocyte metabolic dysfunction. The ECM regulates adipocyte metabolism. Nondiabetic ECM rescues metabolic dysfunction in DM adipocytes, whereas DM ECM imparts features of metabolic dysfunction to nondiabetic adipocytes. These findings suggest the ECM as a target for manipulating adipose tissue metabolism.