Seasonal variations and trends in weight and arm circumference of non-pregnant rural Senegalese women, 1990–1997

Jeketera²,

Intl J Gynecology & Obste

2010

Section: Discussionmentioning

confidence: 77%

Obesity and its outcomes among pregnant South African women

Jeketera²,

Intl J Gynecology & Obste

2010

“…Several studies of subsistence agriculturalists also point to a negative energy balance during seasons when the activity of the community is at its highest. The average body mass of 3,869 Senegalese women declined by 2.5-3.9 kg during the summer months; vigorous agricultural work was presumed to have caused a negative energy balance, although at the same time arm circumferences had increased by an average of 1 mm/month (Simondon et al 2008). Similarly, the body mass of Thai rice farmers showed a seasonal decrease of 1.3 kg in males and 2.5 kg in females, apparently with little associated change in energy intake, suggesting that food intake had not increased to meet seasonal increases in energy expenditure (Murayama 2005).…”

Section: Under-developed Societiesmentioning

confidence: 98%

Seasonal variations in physical activity and implications for human health

2009

This review explores the implications of seasonal changes in physical activity for fitness and human health. Photosensitivity and nutrient shortages mediate animal hibernation via the hypothalamus and changes in leptin and ghrelin concentrations. Opportunities for hunting and crop cultivation determine seasonal activity in under-developed human societies, but in developed societies temperature and rainfall are dominant influences, usually over-riding innate rhythms. Both questionnaire data and objective measurements show that many groups from children to the elderly increase their physical activity from winter to spring or summer. Measurements of maximal oxygen intake and muscle strength commonly show parallel seasonal changes. However, potential effects upon body mass and body fat may be counteracted by changes of food intake; subsistence agriculturists sometimes maintain or increase physical activity at the expense of a decrease in body mass. In developed societies, body fat commonly increases during the winter, with parallel changes in blood lipids, blood pressure and blood coagulability; moreover, these changes are not always fully reversed the following summer. Most developed societies show increased all-cause and cardiac mortalities in the winter. Health consequences of seasonal variations in physical activity including an increased vulnerability to cardiac catastrophe and a year-by-year increase in total body fat seem most likely if the average level of physical activity for the year is low. Public health recommendations should underline the importance of maintaining physical activity during adverse environmental conditions by adapting clothing, modifying behaviour and exploiting any available air-conditioned indoor facilities.

“…37 Women of a nonpregnant rural African female population, the Senegalese women, tended to have higher weight in dry season (March and April), followed by lower weight in rainy season (September-November) at the end of each year, when agricultural labor consumed the stored energy. 38 A longitudinal study involving 202 Chinese infants in Chengdu City and 174 Hong Kong infants in their first 2 years of life showed that the weight gained faster in winter and slower in summer. 39 Thus, statistical analysis using only one cross-sectional BMI measurement is likely to yield biased conclusion.…”

Section: Discussionmentioning

confidence: 99%

“…As season changes affect weight gain, [37][38][39] we took cautions in choosing an appropriate parameter to reflect the situation. In addition, possible statistical biases were avoided by including covariates in the analysis.…”

Section: Methodsmentioning

confidence: 99%

ADRA1A gene is associated with BMI in chronic schizophrenia patients exposed to antipsychotics

et al. 2009

Noradrenaline and adrenaline are neurotransmitters of the sympathetic nervous system that interact with various adrenergic receptor (ADR) subtypes, and this regulates the basal metabolic rate, thermogenesis and efficiency of energy utilization. We examined a possible role of the gene coding for ADRA1A receptor in weight gain in schizophrenia subjects exposed to antipsychotics. A total of 401 schizophrenia in-patients treated with antipsychotics for 42 years were recruited and a final 394 DNA samples were genotyped. Their body mass indexes (BMIs) were recorded for 12 months and parameterized to be correlated in regression. Among the 58 single-nucleotide polymorphisms (SNPs) genotyped, 44 valid SNPs, which had minor allele frequency X0.03, were analyzed in statistics. Linear regression model with age, gender, diabetes, use of typical antipsychotics and use of atypical antipsychotics as covariates, with or without gender interaction, showed evidence of associations between the ADRA1A gene and BMI. Most of the SNPs associated with BMI are located in the promoter and intron regions, and being female appeared to enhance the gene effect. Our study suggests that the ADRA1A gene is involved in weight gain among schizophrenia patients treated with antipsychotics. Further molecular dissection of the ADRA1A gene warrants better understanding on weight gain mechanisms in schizophrenia.