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Few studies have explored pre-pregnancy diet and its relationship with pregnancy outcomes. The objectives of this study were to: (1) derive pre-pregnancy dietary patterns for women enrolled in a prospective cohort in the province of Alberta, Canada; (2) describe associations between dietary patterns and socio-demographic characteristics; and (3) describe associations between dietary patterns and pregnancy complications. Upon enrolment into the Alberta Pregnancy Outcomes and Nutrition (APrON) study (median age of gestation, 17 weeks), women ( n = 1545) completed a validated 142-item food frequency questionnaire recording food and beverages consumed "in the 12 months prior to pregnancy". Other assessments included pre-pregnancy body mass index (BMI), gestational weight gain, gestational hypertension, gestational diabetes, and socio-demographic characteristics. Dietary patterns were derived using principal components analysis. Scores were calculated to represent adherence with each dietary pattern retained. Four dietary patterns were retained, accounting for 22.9% of the variation in the overall diet. Dietary patterns were named the "healthy", "meat and refined carbohydrate", "beans, cheese and salad" or "tea and coffee" patterns. Higher "healthy" pattern scores prior to pregnancy were associated with lower odds of developing gestational hypertension during pregnancy (adjusted Odds Ratio (OR): 0.6, 95% Confidence Intervals (CI): 0.4, 0.9). Diet prior to pregnancy is an important target for interventions and may reduce the likelihood of developing complications such as gestational hypertension during pregnancy.

Although obesity is a known risk factor for diabetes, the impact of body mass index (BMI) changes over time, especially BMI reduction, on diabetes development is less than clear. The objective of this study is to characterize the association between BMI changes over time and incidence of diabetes in a cohort of adults in Alberta. From 2000 to 2008, Alberta's Tomorrow Project (ATP) enrolled participants aged 35-69 to a population-based prospective cohort study. BMI was calculated from self-reported height and weight; change in BMI (∆BMI) was calculated as the difference between baseline and follow-up measurements. Diabetes cases were identified using the Canadian National Diabetes Surveillance System algorithm applied to linked administrative data (2000-2015). Multivariable Cox regression was used to examine the association between ∆BMI and incidence of diabetes. In a subset of the ATP cohort (n=19,164), 1168 incident cases of diabetes were identified during 198,853person-years of follow-up. Overall, BMI increase was associated with increased risk and BMI reduction was associated with reduced risk of diabetes. Particularly, compared to minimal BMI change (±5%), moderate (5%-10%) reduction in BMI was associated with 34% (95% CI: 12%-51%) reduction in risk of diabetes in participants with obesity; whereas 10% or greater increase in BMI was associated with an increased risk of diabetes of 64% or more in participants with overweight and obesity; in participants with normal and underweight, BMI changes was not apparently associated with risk of diabetes. Public health programs promoting weight loss, even at a moderate extent, would reduce risk of diabetes., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Choosing the most appropriate dietary assessment tool for a study can be a challenge. Through a scoping review, we characterized self-report tools used to assess diet in Canada to identify patterns in tool use and to inform strategies to strengthen nutrition research. The research databases Medline, PubMed, PsycINFO, and CINAHL were used to identify Canadian studies published from 2009 to 2014 that included a self-report assessment of dietary intake. The search elicited 2358 records that were screened to identify those that reported on self-report dietary intake among nonclinical, non-Aboriginal adult populations. A pool of 189 articles (reflecting 92 studies) was examined in-depth to assess the dietary assessment tools used. Food-frequency questionnaires (FFQs) and screeners were used in 64% of studies, whereas food records and 24-h recalls were used in 18% and 14% of studies, respectively. Three studies (3%) used a single question to assess diet, and for 3 studies the tool used was not clear. A variety of distinct FFQs and screeners, including those developed and/or adapted for use in Canada and those developed elsewhere, were used. Some tools were reported to have been evaluated previously in terms of validity or reliability, but details of psychometric testing were often lacking. Energy and fat were the most commonly studied, reported by 42% and 39% of studies, respectively. For ∼20% of studies, dietary data were used to assess dietary quality or patterns, whereas close to half assessed ≤5 dietary components. A variety of dietary assessment tools are used in Canadian research. Strategies to improve the application of current evidence on best practices in dietary assessment have the potential to support a stronger and more cohesive literature on diet and health. Such strategies could benefit from national and global collaboration., (© 2017 American Society for Nutrition.)

Biospecimens are the essential substrates for human biomarker research. Across the globe, biobanks have developed the facilities and mechanisms to collect, process, store and distribute those substrates to researchers. However, despite some notable successes, less than one hundred of the tens of thousands of purported biomarkers have been independently validated. We propose the need for a new paradigm in biobanking; simply pursuing larger numbers of participants, larger networks of biobanks and higher sample integrity will not, in itself, transform the success rate or efficiency of biomarker research. We propose that biobanks must embrace the intrinsic observational nature of biospecimens and furnish the recipients of biospecimens with the population metrics (descriptive statistics) that can facilitate the scientific rigor that is mandated in other areas of observational research. In addition, we discuss the value of population-based ascertainment and recruitment and the importance of the timing of biospecimen collections. Any assessment of biospecimen quality must go beyond the sample itself and consider both the patient/participant selection and the most appropriate and informative timing for specimen collection, particularly prior to any treatment intervention in diseased populations. The examples and rationales that we present are based largely on cancer-related collections because the feasibility of population metrics is greatly assisted by the comprehensive registries that are more common for cancer than other chronic diseases. Changing the biobanking paradigm from tacitly 'experimental' to explicitly 'observational' represents a profound but urgent methodological shift that will influence the establishment, management, reporting and impact of biobanks in the twenty-first century.

Background: To understand, prevent, and manage weight-related health issues, researchers and clinicians rely on the ability to identify those at risk. Prevention and management strategies may also rely on accurate self-perception of weight and body composition in the general population., Methods: We analyzed data from The Tomorrow Project (n = 7,436), a prospective cohort study enrolling adults aged 35-69 years, in Alberta, Canada. Weight perception accuracy was defined based on body mass index (BMI), waist circumference (WC), and a combined (BMI and WC) risk profile., Results: The majority of participants correctly perceived themselves as overweight. Women were more accurate than men in identifying themselves as overweight. In terms of inaccuracy, more normal-weight women than men perceived themselves to be overweight, while more overweight men than women perceived themselves as about the right weight. When using the combined risk profile, all men with normal weight (BMI) but higher risk WC perceived their weight as about right whereas just under half of men who were overweight (BMI) but lower risk WC perceived their weight as about right. For women, a much higher proportion recognized their weight status as overweight when only BMI was elevated compared to when only WC indicated higher risk., Discussion: Adults in our sample showed reasonable accuracy in weight perception. Gender differences reveal that women were more accurate than men in identifying themselves as overweight. Incongruence between weight status indicators was noted, indicating the importance of using both BMI and waist circumference as health status measures.

Objectives: To determine the numbers of smokers, smoking prevalence and trends, and to examine their socio-demographic associations in Alberta using data from three Canadian national health surveys undertaken between 2000 and 2005., Methods: The three surveys collected self-reported health data from Canadians aged 12 years and older. The weighted number of smokers and the smoking prevalence by health region and by urban/rural status were determined. The socio-demographic associations of smoking in Alberta were examined using logistic regression analysis., Results: The numbers of smokers and the smoking prevalence were both higher among men than women, in middle-aged groups (20-39 and 40-59 years) than in younger (12-19 years) and older (> or = 60 years) groups, and among Canadian-born people than immigrants to Canada. The smoking prevalence tended to 1) increase with the increasing rurality of residence, 2) decrease over the timeframe examined, 3) be inversely proportional to educational level and 4) be inversely proportional to household income. The number of smokers was largest in urban areas and among those who reported the highest education and household income., Discussion: The new tobacco legislation being introduced in Alberta in 2009 may decrease the smoking prevalence in the province, but additional interventions in the regions with the largest numbers of smokers may help further reduce the smoking population and overall smoking prevalence in Alberta.

Objectives: To examine the 12-year trend, in Alberta and Canada, of five modifiable lifestyle risk factors for cancer, and their associations with sociodemographic factors., Methods: Six surveys collected data from Canadians aged > or =12 years. The prevalence, trends, and sociodemographic association of five lifestyle risk factors (smoking, inactivity, excessive drinking, overweight/obesity, and insufficient fruit/vegetable intake) were examined., Results: Smoking and inactivity decreased significantly: by 5.4% and 2.7% (Alberta men) and 4.9% and 12.1% (Alberta women); by 7.5% and 8.5% (Canada men) and 7.7% and 11.9% (Canada women). Excessive drinking increased significantly: by 3.6% (men) and 0.9% (women), Alberta; by 2.5% (men) and 0.9% (women), Canada. Overweight/obesity significantly increased by 6.0% (Alberta) and 4.1% (Canada) in women. Being female, single, highly educated, or having higher income decreased the likelihood of exposure to multiple lifestyle risk factors; being middle aged, widowed/separated/divorced, or in poor health condition increased the likelihood., Conclusions: The downward trends for smoking and physical inactivity were in a direction that may help reduce cancer burden. The excessive drinking and overweight/obesity trends did not change in desired direction and deserve attention. The clustering of the lifestyle risk factors in specific social groups provides useful information for future intervention planning.

Background: The effects of subclinical vitamin D deficiency on bone mineral density (BMD) and bone turnover in adolescents, especially in boys, are unclear., Objective: We aimed to investigate the relations of different stages of vitamin D status and BMD and bone turnover in a representative sample of adolescent boys and girls., Design: BMD was measured by dual-energy X-ray absorptiometry at the nondominant forearm and dominant heel in a random sample of 12- (n = 260) and 15-y-old (n = 239) boys and 12- (n = 266) and 15-y-old (n = 250) girls. Serum 25-hydroxyvitamin D, parathyroid hormone, osteocalcin, and type I collagen cross-linked C-telopeptide were assessed by using enzyme-linked immunoassays. Relations between vitamin D status and bone health indexes were assessed by using regression modeling., Results: Using multivariate regression to adjust for potential physical, lifestyle, and dietary confounding factors, we observed that 12- and 15-y-old girls with high vitamin D status (>/=74.1 nmol/L) had significantly greater forearm (but not heel) BMD (beta = 0.018; SE = 0.008; P < 0.05 for each age group) and lower serum parathyroid hormone concentrations and bone turnover markers than did those with low vitamin D status. These associations were evident in subjects sampled throughout the year and in winter only. There was no significant relation between vitamin D status and BMD in boys., Conclusions: Maintaining serum 25-hydroxyvitamin D concentrations above approximately 50 nmol/L throughout the year may be a cost-effective means of improving bone health. Increased emphasis on exploring strategies for improving vitamin D status in adolescents is needed.

Background: Both folate and betaine are important predictors of total homocysteine (tHcy) during pregnancy. However, studies to date have only been undertaken in populations with Western dietary patterns., Objective: We investigated the predictors of tHcy in pregnant women recruited in the Seychelles, a population where access to fortified foods is limited and where women habitually consume diets rich in fish, eggs, rice, and fruit., Design: Pregnant women (n = 226) provided blood samples at enrollment, at week 28 of gestation, and at delivery. Cord blood was obtained from a subset of participants (n = 135)., Results: As in other studies, maternal tHcy was lower during pregnancy than at delivery, whereas folate and vitamin B-12 status declined significantly to delivery. Despite low maternal folate status at delivery (median: 9.0 nmol/L), with 35% of women in the deficient range (serum folate: <6.8 nmol/L), cord blood folate status (median: 40.2 nmol/L) was similar to concentrations reported in Western populations. Folate was a significant predictor of tHcy at all time points (P < 0.001). In contrast with previous studies, betaine was only a significant predictor of maternal tHcy (P < 0.001) when the essential amino acid methionine was low., Conclusions: The current study reports 2 important findings. First, fetal requirements for folate are paramount, such that cord blood folate status is maintained, even when maternal status is low. Second, betaine is a significant predictor of tHcy in pregnant women with low serum folate and low serum methionine concentrations.

In a climate of increasing privacy concerns, the feasibility of establishing new cohorts to examine chronic disease etiology has been debated. Our primary aim was to ascertain the feasibility of enrolling a geographically dispersed, population-based cohort in Alberta. We also examined whether enrolees would grant access to provincial health care utilization data and consider providing blood for future analysis. Using random digit dialling, 22,652 men and women aged 35 to 69 years, without diagnosed cancer, were recruited. Of these, 52.4 percent (N=11,865) enrolled; 84 percent of Alberta communities were represented. Approximately 97 percent of enrolees consented to linkage with health care data, and 91 percent indicated willingness to consider future blood sampling. Comparisons between the cohort and the Canadian Community Health Survey (Cycle 1.1) for Alberta demonstrated similarities in marital status and income. However, the cohort had a smaller proportion who had not finished high school, a greater proportion of nonsmokers and a higher prevalence of obesity. These findings indicate that establishment of a geographically dispersed cohort is feasible in the Canadian context, and that data linkage and biomarker studies may be viable.

Objective: To examine associations between milk consumption and incident heart disease and stroke., Design: A representative population sample of men was asked to weigh and record their food intake for seven days. The total consumption of milk was obtained from these records. Details of all deaths and vascular events were collected during the following 20 years. Incident ischaemic strokes and heart disease events were diagnosed by standard criteria., Setting: The Caerphilly cohort, a representative population sample of men in South Wales, aged 45-59 when first seen in 1979-83., Participants: A representative 3:10 subsample of the men in the cohort., Main Results: 665 men (87% of those approached) returned satisfactory seven day diet diaries. After adjustment, the relative odds of an event in the men whose milk consumption was the median or higher, relative to those with lower intakes of milk, were 0.52 (0.27 to 0.99) for an ischaemic stroke and 0.88 (0.56 to 1.40) for an ischaemic heart disease event. Deaths from all causes were similar in the two milk consumption groups (relative odds 1.08; 0.74 to 1.58)., Conclusions: These results give no convincing evidence of an increased risk of vascular disease from milk drinking. Rather, the subjects who drank more than the median amount of milk had a reduced risk of an ischaemic stroke, and possibly a reduced risk of an ischaemic heart disease event. These conclusions are in agreement with the results of a previously reported overview of 10 large, long term cohort studies based on food frequency intake records.

The unexplained underperformance syndrome (UPS), previously known as the overtraining syndrome (OTS), has been defined as a persistent decrement in athletic performance capacity despite 2 weeks of relative rest. It has been proposed that UPS may be caused by excessive cytokine release during and following exercise causing a chronic inflammatory state and 'cytokine sickness'. This article extends that hypothesis by proposing that time-dependent sensitisation could provide a model through which the aetiology of UPS may be explained. In this model, the principal abnormal factors in UPS are an increased production of and/or intolerance to interleukin (IL)-6 during exercise. Strategies to attenuate the IL-6 response to exercise that may also reduce an athlete's susceptibility to UPS are proposed.

The aim of this study was to investigate the endotoxin-induced interleukin-6 (IL-6) release in whole blood cultures from samples taken at rest, 24 h post-exercise, from a control group of recreationally trained individuals (C), a group of highly trained triathletes (TA) and a group of highly trained professional rugby players (RP). Fifteen RP [mean (SD): age 26 (3) years, height 1.90 (0.2) m, body mass 104.5 (12.2 kg)], 13 male TA [age 33 (5) years, height 1.78 (0.1) m, body mass 76.3 (12.6) kg] and eight recreationally active male volunteers [age 28 (6) years, height 1.80 (0.1) m, body mass 72.3 (7.3) kg] participated in the study. Plasma IL-6 concentration and in vitro IL-6 synthesis by whole blood cultures were measured in samples taken at rest. Plasma IL-6 concentration was significantly higher ( P<0.01) for the RP and TA groups than for C, as were the in vitro basal and endotoxin activated concentrations. However, after endotoxin stimulation, newly induced IL-6 concentration was significantly lower ( P<0.01) in the RP and TA than in the C group. Therefore, professional rugby players have a similar IL-6 release of whole blood cultures in vitro to that of triathletes. Specifically, mononuclear cells appear to be chronically activated to spontaneously release IL-6, but have a decreased capacity to respond to a further stimulus. Amongst possible explanations for this, the most likely is counter-regulation due to already elevated IL-6 release.