Intermitterend vasten en de effecten op overgewicht en cardiometabole gezondheid: wetenschap en praktijk

• Intermittent Fasting (IF) is a broad concept and covers several fasting regimes. • Studies of 'early time restricted feeding' and 'alternate day fasting' with energy restriction show a greater effect on weight and cardiometabolic health in overweight people in the short term, compared to a continuous caloric restriction (CCR). 'Late time restricted feeding' seems to have no or unfavorable effects. • Long-term studies (up to 2 years) suggest that IF regimens are not superior to continuous caloric restriction. • The few studies available show a similar compliance and metabolic adaptation between IF and CCR. • There is insufficient knowledge about long-term safety in various groups of people, the influence of dietary quality and the practical feasibility of IF regimes. • As a result, no recommendations can yet be made on the use of IF in the treatment of overweight and related diseases

Sexual dimorphism in cortisol metabolism throughout pubertal development: a longitudinal study

Objective: Sex differences in disease susceptibility might be explained by sexual dimorphism in hypothalamic-pituitary-adrenal axis activity, which has been postulated to emerge during puberty. However, studies conducted thus far lacked an assessment of Tanner pubertal stage. This study aimed to assess the contribution of pubertal development to sexual dimorphism in cortisol production and metabolism. Methods: Participants (n = 218) were enrolled from a population-based Netherlands Twin Register. At the ages of 9, 12 and 17 years, Tanner pubertal stage was assessed and early morning urine samples were collected. Cortisol metabolites were measured with GC-MS/MS and ratios were calculated, representing cortisol metabolism enzyme activities, such as A-ring reductases, 11β-HSDs and CYP3A4. Cortisol production and metabolism parameters were compared between sexes for pre-pubertal (Tanner stage 1), early pubertal (Tanner stage 2–3) and late-pubertal (Tanner stage 4–5) stages. Results: Cortisol metabolite excretion rate decreased with pubertal maturation in both sexes, but did not significantly differ between sexes at any pubertal stage, although in girls a considerable decrease was observed between early and late-pubertal stage (P < 0.001). A-ring reductase activity was similar between sexes at pre-and early pubertal stages and was lower in girls than in boys at late-pubertal stage. Activities of 11β-HSDs were similar between sexes at pre-pubertal stage and favored cortisone in girls at early and late-pubertal stages. Cytochrome P450 3A4 activity did not differ between sexes. Conclusions: Prepubertally, sexes were similar in cortisol parameters. During puberty, as compared to boys, in girls the activities of A-ring reductases declined and the balance between 11β-HSDs progressively favored cortisone. In addition, girls showed a considerable decrease in cortisol metabolite excretion rate between early and late-pubertal stages. Our findings suggest that the sexual dimorphism in cortisol may either be explained by rising concentrations of sex steroids or by puberty-induced changes in body composition

Interpretation of glucocorticoids in neonatal hair: A reflection of intrauterine glucocorticoid regulation?

Background: Glucocorticoids (GCs) measured in neonatal hair might reflect intrauterine as well as postpartum GC regulation. We aimed to identify factors associated with neonatal hair GC levels in early life, and their correlation with maternal hair GCs. Methods: In a single-center observational study, mother-infant pairs (n = 107) admitted for >72 h at the maternity ward of a general hospital were included. At birth and an outpatient visit (OPV, n = 72, 44 ± 11 days postpartum), maternal and neonatal hair was analyzed for cortisol and cortisone levels by LC-MS/MS. Data were analyzed regarding: (1) neonatal GC levels postpartum and at the OPV, (2) associations of neonatal GC levels with maternal GC levels and (3) with other perinatal factors. Results: (1) Neonatal GC levels were >5 times higher than maternal levels, with a decrease in ±50% between birth and the OPV for cortisol. (2) Maternal and neonatal cortisol, but not cortisone, levels were correlated both at postpartum and at the OPV. (3) Gestational age was associated with neonatal GC postpartum (log-transformed β (95% CI): cortisol 0.07 (0.04-0.10); cortisone 0.04 (0.01-0.06)) and at the OPV (cortisol 0.08 (0.04-0.12); cortisone 0.00 (-0.04 to 0.04)), while weaker associations were found between neonatal GCs and other perinatal and maternal factors. Conclusions: Neonatal hair GCs mainly reflect the third trimester increase in cortisol, which might be caused by the positive feedback loop, a placenta-driven phenomenon, represented by the positive association with GA. Between birth and 1.5 months postpartum, neonatal hair cortisol concentrations decrease sharply, but still appear to reflect both intra- and extrauterine periods

Diurnal rhythmicity in breast-milk glucocorticoids, and infant behavior and sleep at age 3 months

Purpose: In previous studies, associations between breast-milk cortisol levels obtained on one occasion and infant neurodevelopment were demonstrated. However, more recent evidence indicates that breast-milk cortisol and cortisone concentrations follow the diurnal rhythm of maternal hypothalamus-pituitary-adrenal axis, peaking in the early morning and with a nadir at midnight. We studied associations between breast-milk glucocorticoid (GC) rhythmicity, and infant behavior and sleep. Methods: We included 59 mothers, and their infants, of whom 17 had consulted an expert center during pregnancy for an increased risk of psychological distress. At 1 month postpartum, breast milk was sampled (on averag

An exploratory study of perinatal hair cortisol concentrations in mother–infant dyads with severe psychiatric disorders versus healthy controls

Background Maternal psychopathology during pregnancy is associated with negative outcomes in offspring. Increased placental transfer of maternal cortisol may contribute to mediate this association. Hair cortisol concentrations (HCCs) appear to be a good biomarker of long-term prenatal stress exposure. Little is known about the associations between severe maternal psychopathology and perinatal infant HCCs. Aims We assessed HCCs in the perinatal period in mother–infant dyads with and without severe psychiatric disorders. Method We examined group differences in HCCs of mother–infant dyads (n = 18) subjected to severe maternal psychiatric disorders versus healthy control dyads (n = 27). We assessed the correlation of HCCs between mother and infant within both groups, and the association between current maternal symptoms and HCCs in patient dyads. Results Median (interquartile range) and distribution of HCC differed in patients compared with control mothers (U = 468.5, P = 0.03). HCCs in infants of patients did not differ from control infants (U = 250.0, P = 0.67). Subsequently, we found that HCCs within healthy control dyads were correlated (n = 27, r 0.55 (0.14), P = 0.003), but were not within patient dyads (n = 18, r 0.082 (0.13), P = 0.746). HCCs in infants of patients showed a positive correlation with maternal symptoms (n = 16, r = 0.63 (0.06), P = 0.008). Conclusions These preliminary findings suggest that infant HCC reflect perinatal stress exposure. In infants, these early differences could influence lifetime hypothalamic–pituitary–adrenal axis functioning, which might be associated with increased susceptibility to later disease

Nudging strategies to improve food choices of healthcare workers in the workplace cafeteria: A pragmatic field study

Background & aims: Dutch healthcare workers experience the highest workload and absenteeism rates compared to all other professions. This has been associated with a more unhealthy diet. Nudging strategies in the workplace have been shown to improve food choices. We studied the potential of a combination of evidence and practice-based nudging strategies; determined their feasibility in a real-life setting; and explored their effectiveness on healthier purchases over a two-month period in a hospital workplace cafeteria. Methods: We conducted an explorative, prospective field study. Based on information gathered through a literature search and a qualitative field study, we selected the potentially most effective and feasible nudges. These were subsequently implemented in a commercial workplace cafeteria of a Dutch academic medical centre. The selected nudging strategies included product placement, increasing the ratio of healthy to unhealthy product options, and providing nutritional information and motivational statements. Data on the products purchased was collected using photographs of the lunch trays of healthcare workers, with the products then labelled and their nutritional value calculated. Effects were evaluated after one and two months. Chi-square analyses were used to analyse differences over time. Results: A total of 905 photographs of lunches were analysed (approximately 300 at each time point). The nudging strategies implemented resulted in a 41% increase in the purchase of whole-wheat products at the expense of non-whole-wheat products, between baseline and final measurement (p = 0.012). The purchases of healthy and unhealthy bread fillings and beverages did not significantly change during the study period. Conclusion: This explorative study showed that a combination of three nudging strategies partly improved healthy food choices for lunch in a Dutch healthcare setting. These results may help guide other professionals to implement nudging strategies to improve employee food choices. Future research should evaluate the effect over a longer period of time, thereby identifying the most effective combination of nudging strategies and investigate how these effect the health of hospital employees