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Body fat, energy balance and estradiol levels: a study based on hormonal profiles from complete menstrual cycles
BACKGROUND: Female fecundity is regulated by nutritional status. Although widely cited, this hypothesis is not strongly supported by empirical data from non-obese, healthy women of reproductive age. METHODS: Healthy, reproductive aged women (n = 141) from Southern Poland collected daily morning saliva samples for one complete menstrual cycle. Levels of 17-b-estradiol were analyzed by radioimmunoassay. Anthropometric measurements, including body fat percentage, were taken randomly with respect to phase of the menstrual cycle. Energy balance was specified based on changes in body fat percentage from the beginning to the end of the observation period.
RESULTS: Women with very low and high body fat had significantly lower levels of E2 compared with women with low and average body fat. In women of very low to average body fat, a 10% increase in body fat was associated with a 5 – 7 pmol/l increase in estradiol levels. The association between fat percentage and E2 was even stronger in women with positive energy balance, who also showed significant differences between body fat groups in estradiol profiles across whole the menstrual cycle. No such relationship was found in women with negative energy balance.
CONCLUSIONS: In healthy women, we found a non-linear association between body fat and estradiol levels. Both very low and high body fat was associated with decreased estradiol levels. The relationship between estradiol and body fat was strongly influenced by women’s energy balance.AnthropologyHuman Evolutionary Biolog
Specialist English as a foreign language for European public health : evaluation of competencies and needs among Polish and Lithuanian students
Foreign languages are becoming an essential prerequisite for a successful carrier among all professions including public health professionals in many countries. The expanding role of English as a mode of communication allows for university graduates to project and to seek their career in English-speaking countries. The present study was carried out in the framework of EU Leonardo da Vinci project “Specialist English as a foreign language for European public health.” The study aimed to get a deeper insight how the English language is perceived as a foreign language, by Polish and Lithuanian public health students, what is level of their language competence, which level of English proficiency they expect to use in future.Material and methods. A total of 246 respondents completed the special questionnaires in autumn semester in 2005. A questionnaire form was developed by the international project team. For evaluation of English competences, the Language Passport (Common European Framework of Reference for Languages of Council of Europe) was applied. Results. Current self-rated proficiency of the English language was at the same level for Lithuanian (3.47±1.14) and Polish (3.31±0.83) respondents (P>0.05). Majority of respondents (88.6% of Lithuanian and 87.8% of Polish) reported using the English language for their current studies. Respondents reported a significant increase in necessity for higher level of English proficiency in future: mean scores provided by respondents changed from B1 level to B2 level. Respondents gave priority to less formal and practice-based interactive English teaching methods (going abroad, contacts with native speakers) in comparison with theory-oriented methods of learning (self-studying, Internet courses). Conclusions. Similar levels of English language in all five areas of language skills were established in Polish and Lithuanian university students. Respondents gave more priorities to less formal and practice-based interactive English teaching methods (going abroad, contacts with native speakers) in comparison with theory-oriented or classroom-based methods of learning (self-studying, Internet courses). Survey showed a growing interest of students in improving English language in the future in Poland and Lithuania
Evidence for the cost of reproduction in humans : high lifetime reproductive effort is associated with greater oxidative stress in post-menopausal women
Life history theory predicts trade-offs between reproductive effort and maternal survivorship in energy-restricted environments. However, empirical evidence for the positive association between maternal mortality and reproductive effort from energetically challenged human populations are mixed and physiological mechanisms that may underlie this association are poorly understood. We hypothesized that increases in aerobic metabolism during repeated periods of pregnancy and lactation result in increased oxidative stress that may contribute to somatic deterioration, vulnerability to illness, and accelerated aging. We therefore predicted that lifetime gravidity and parity would be related to levels of biomarkers of oxidative stress, as well as antioxidative defence enzymes in post-menopausal women. Our hypothesis was supported by positive linear associations between levels of 8-OHdG, a biomarker of DNA oxidative damage (β = 0.21, p = 4 pregnancies per lifetime) had 20% higher levels of 8-OHdG and 60% higher levels of Cu-Zn SOD compared to women with lower gravidity and parity (<4 pregnancies per lifetime). Our results present the first evidence for oxidative stress as a possible cost of reproductive effort in humans
Shifts in Female Facial Attractiveness during Pregnancy
It has been proposed that women’s physical attractiveness is a cue to temporal changes in fertility. If this is the case, we should observe shifts in attractiveness during pregnancy—a unique physiological state of temporal infertility. The aim of this study was to examine how women’s facial attractiveness changes during the subsequent trimesters of pregnancy and how it compares to that of nonpregnant women. Sixty-six pictures of pregnant women (22 pictures per trimester) and 22 of nonpregnant women (a control group) were used to generate four composite portraits, which were subsequently assessed for facial attractiveness by 117 heterosexual men. The results show considerable differences between facial attractiveness ratings depending on the status and progress of pregnancy. Nonpregnant women were perceived as the most attractive, and the attractiveness scores of pregnant women decreased throughout the course of pregnancy. Our findings show that facial attractiveness can be influenced by pregnancy and that gestation, even at its early stages, affects facial attractiveness. Considerable changes in women’s physiology that occur during pregnancy may be responsible for the observed effects
Human milk: From complex tailored nutrition to bioactive impact on child cognition and behavior
Human milk is a highly complex liquid food tailor-made to match an infant's needs. Beyond documented positive effects of breastfeeding on infant and maternal health, there is increasing evidence that milk constituents also impact child neurodevelopment. Non-nutrient milk bioactives would contribute to the (long-term) development of child cognition and behavior, a process termed 'Lactocrine Programming'. In this review we discuss the current state of the field on human milk composition and its links with child cognitive and behavioral development. To promote state-of-the-art methodologies and designs that facilitate data pooling and meta-analytic endeavors, we present detailed recommendations and best practices for future studies. Finally, we determine important scientific gaps that need to be filled to advance the field, and discuss innovative directions for future research. Unveiling the mechanisms underlying the links between human milk and child cognition and behavior will deepen our understanding of the broad functions of this complex liquid food, as well as provide necessary information for designing future interventions
Human milk: From complex tailored nutrition to bioactive impact on child cognition and behavior
Human milk is a highly complex liquid food tailor-made to match an infant's needs. Beyond documented positive effects of breastfeeding on infant and maternal health, there is increasing evidence that milk constituents also impact child neurodevelopment. Non-nutrient milk bioactives would contribute to the (long-term) development of child cognition and behavior, a process termed 'Lactocrine Programming'. In this review we discuss the current state of the field on human milk composition and its links with child cognitive and behavioral development. To promote state-of-the-art methodologies and designs that facilitate data pooling and meta-analytic endeavors, we present detailed recommendations and best practices for future studies. Finally, we determine important scientific gaps that need to be filled to advance the field, and discuss innovative directions for future research. Unveiling the mechanisms underlying the links between human milk and child cognition and behavior will deepen our understanding of the broad functions of this complex liquid food, as well as provide necessary information for designing future interventions.All authors participated in the four-day hybrid meeting on ‘Lactational Programming: joining forces to optimize research on how maternal milk composition influences child cognition and behavior’ (Zeist, the Netherlands, 16-19 November 2020), which was financed by an Early Career Partnership 2020 Grant of the Royal Netherlands Academy of Arts and Sciences (awarded to Beijers). Funding sources for individual authors: Netherlands Organization for Scientific Research VICI grant (016.Vici.185.038-to de Weerth), The National Center for Advancing Translational Sciences Clinical Science and Translational Award (UL1TR001863-to Dettmer), NWO Food Cognition and Behaviour (057-14-003-to Korosi), Turku University Foundation, Maire Taponen Foundation and Finnish Psychiatry Foundation (-to Aatsinki), Polish National Science Centre OPUS grant (2015/17/B/NZ8/02436 -to Ziomkiewicz), Canadian Research Chair in Human Nutrition and Metabolism and funding from Natural Science and Engineering Council of Canada NSERC (RGPIN-2017-04746-to Field), The USDA National Institute of Food and Agriculture Hatch Project (1021411-to Slupsky), USDA NRI (2007-35203-18098 and 2013-67016-20523-to Bartol), Spanish Ministry of Science and Innovation grant (PID2019-105606RB-I00-to Rodríguez), UC San Diego Chair of Collaborative Human Milk Research, endowed by the Family Larsson-Rosenquist Foundation, Switzerland (-to Bode), Wellcome Trust (220225/Z/20/Z-to Moore), Tier 2 Canada Research Chair and Fellow in the CIFAR Humans and the Microbiome Program, Canadian Institutes of Health Research (CIHR), Research Manitoba, the Canada Foundation for Innovation, the Bill and Melinda Gates Foundation, the Manitoba Children’s Hospital Foundation, Prolacta Biosciences, Mitacs, CIFAR, and the Garfield G. Weston Foundation (-to Azad), CIHR Vanier Canada Graduate Scholarship (-to Turner), European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (ERC starting grant, no. 639226-to Collado), Netherlands Organization for Scientific Research VENI grant (016.195.197-to Beijers).Peer reviewe
Grow first, gain fat in the meantime. Longitudinal study of anthropometric changes around menarche
There is a long dispute among anthropologist over which factor is more important – skeletal maturation or energy accumulation – for menarche occurrence. Here we report results of longitudinal study conducted on the sample of 178 girls followed for the period from 2 years before to 2 years after the age of menarche. Each year during this period anthropometric measures of waist and hip circumference, pelvis breadth, subscapular, triceps and abdominal skinfold thickness were taken to document girls’ physical development. We found that changes in hip circumference and pelvis breadth were the most closely associated with menarche appearance. We also found that changes in anthropometric measures of lower body part preceded changes in anthropometric measures of upper body part and tended to peak one year before menarche occurrence while changes in upper body part tended to peak one year after menarche occurrence. These results suggest that both skeletal maturation and energy accumulation in the form of fat are equally important for menarche to occur. Furthermore, we are proposing a new indicator describing allometric changes of pelvis around menarche: hip circumference to pelvis breadth ratio (HCPBR)