Micronutrient status of New Zealand adolescent women consuming vegetarian and non-vegetarian diets.

BACKGROUND AND OBJECTIVES: Globally, there appears to be an ever-increasing interest in adopting a vegetarian diet. However, there are concerns that avoiding meat may increase the risk of anaemia and micronutrient deficiencies, especially for vulnerable populations, such as adolescent women. The objective of this study was to compare the micronutrient status of vegetarian and non-vegetarian adolescent women in New Zealand. METHODS AND STUDY DESIGN: Adolescent women aged 15-18 y were recruited from eight locations across New Zealand. Blood samples were analysed for: haemoglobin, serum ferritin, soluble transferrin receptor, zinc, selenium, retinol binding protein, folate, vitamin B-12, vitamin D and parathyroid hormone. RESULTS: Of the 182 participants who provided a blood sample, 15% self-identified as vegetarian (n=27). On average, vegetarians had 3.1% (95% CI -5.8 to -0.4, p=0.025) lower haemoglobin, and 8.3% (95%CI -14.1 to -2.1, p=0.004) lower selenium. In contrast, serum folate was 80.5% (95% CI 45.7 to 123.7, p<0.001) higher. The prevalence of zinc and selenium deficiency was higher among vegetarians (50% and 12%, respectively) than non-vegetarians (21%, and 2%, respectively). CONCLUSIONS: Adolescent vegetarian women may be at increased risk of deficiency of micronutrients commonly found in animal products, including zinc and selenium, and may benefit from following dietary practices that enhance micronutrient intake and absorption.

Rationalisation of meat consumption in New Zealand adolescents.

OBJECTIVE: This study aimed to describe meat consumption rationalisation and relationships with meat consumption patterns and food choice motivations in New Zealand adolescents. DESIGN: This was a cross-sectional study of adolescents from high schools across New Zealand. Demographics, dietary habits, and motivations and attitudes towards food were assessed by online questionnaire and anthropometric measurements taken by researchers. The 4Ns questionnaire assessed meat consumption rationalisation with four subscales: 'Nice', 'Normal', 'Necessary' and 'Natural'. SETTING: Nineteen secondary schools from eight regions in New Zealand, with some purposive sampling of adolescent vegetarians in Otago, New Zealand. PARTICIPANTS: Questionnaires were completed by 385 non-vegetarian and vegetarian (self-identified) adolescents. RESULTS: A majority of non-vegetarian adolescents agreed that consuming meat was 'nice' (65 %), but fewer agreed that meat consumption was 'necessary' (51 %). Males agreed more strongly than females with all 4N subscales. High meat consumers were more likely to agree than to disagree that meat consumption was nice, normal, necessary and natural, and vegetarians tended to disagree with all rationalisations. Adolescent non-vegetarians whose food choice was motivated more by convenience, sensory appeal, price and familiarity tended to agree more with all 4N subscales, whereas adolescents motivated by animal welfare and environmental concerns were less likely to agree. CONCLUSIONS: To promote a reduction in meat consumption in adolescents, approaches will need to overcome beliefs that meat consumption is nice, normal, necessary and natural.

Predicting height from ulna length for the determination of weight status in New Zealand adolescents: A cross-sectional study.

BACKGROUND: The measurement of height is crucial for weight status assessment. When standing height is difficult to measure, ulna length may offer a convenient and accurate surrogate of height measure. Adolescence is a period of accelerated linear growth; hence, the validation of age-specific equations that predict height from ulna length in adolescents is warranted. The present study aimed to develop and validate age- and sex-specific equations for predicting height from ulna length in New Zealand adolescents. METHODS: Height, weight and ulna length were measured in 364 adolescents (n = 110 males, n = 254 females) aged 15.0-18.8 years, who were enrolled in the SuNDiAL (Survey of Nutrition Dietary Assessment and Lifestyle) project, a cross-sectional survey performed in 2019 and 2020. Regression models were used to determine equations to predict height from ulna length. Agreement between measured and predicted height, body mass index (BMI) and BMI z-score was assessed with intra-class correlation coefficients (ICC) and Bland-Altman plots. Sensitivity and specificity were calculated for classifying obesity. RESULTS: Strong agreement was found between predicted and measured height (ICC = 0.78; mean difference = 0; 95% confidence interval = -0.5 to 0.5 cm) and BMI (ICC = 0.95; mean difference = 0; 95% confidence interval = -0.1 to 0.1 kg m-2 ). Predicted height was 88.1% accurate when classifiying weight status, showing high sensitivity (93.8%) and specificity (99.4%) for classifying obesity. CONCLUSIONS: Ulna length measurement can accurately estimate height and subsequently weight status in New Zealand adolescents aged 15-18 years.

Feasibility and Pilot Outcomes of the Move More @ Work Intervention Designed to Encourage Employees to be Physically Active for 2 Minutes After Every 30 Minutes of Sitting.

OBJECTIVE: The aim of the study is to evaluate the feasibility of a workplace intervention supporting employees to interrupt sitting time with short bouts of activity (termed an opportunity to move [OTM]). METHODS: Using an interrupted time series design, 58 sedentary employees provided baseline assessments of physical activity, health, and work-related outcomes and completed the 12-week intervention. Assessments were repeated immediately and 12 weeks after intervention. Focus groups explored intervention acceptability. RESULTS: Accelerometer data showed no change in the number of OTMs taken before to after intervention, while participants self-reported 62-69% intervention adherence. Physical activity at work, productivity, and musculoskeletal health improved but cardiometabolic health and psychological well-being did not. Intervention components were viewed favorably (pending amendments), but taking an OTM every 30 minutes was not feasible. CONCLUSIONS: The Move More @ Work intervention has potential, but adaptations are required to increase adherence.

A Sample of Female Adolescent Self-Identified Vegetarians in New Zealand Consume Less Protein and Saturated Fat, but More Fiber than Their Omnivorous Peers.

This study aimed to describe the intake and food sources of macronutrients in vegetarian and non-vegetarian adolescent females. Cross-sectional data was collected between February and September 2019. Adolescent females, aged 15 to 18 years old, were recruited throughout New Zealand. Intakes were assessed via two 24-h diet recalls, adjusted to represent usual intake using the multiple source method. Of the 254 participants, 38 self-identified as vegetarian. Vegetarians had similar carbohydrate and fat intakes compared to non-vegetarians; however, their protein intakes were 2.1% kJ lower (95% confidence interval (CI) -3.0 to -1.1%). Vegetarians also consumed 1.1% kJ less saturated fat (95% CI -2.1 to -0.1%), 1.3% kJ (95% CI 0.7 to 1.9) more polyunsaturated fat, and 5 g/day (95% CI 1.8 to 8.0) more fiber than non-vegetarians. When consumed, bread-based dishes and discretionary foods were the highest sources of energy, fat, and carbohydrate in both vegetarians and non-vegetarians. This suggests that some adolescents, including vegetarians, were obtaining high amounts of fat and carbohydrate from food groups associated with poorer dietary quality. We recommend further research to assess how the changing food environment is influencing vegetarian eating patterns and their associations with health outcomes in the wider population.

Using a 24 h Activity Recall (STAR-24) to Describe Activity in Adolescent Boys in New Zealand: Comparisons between a Sample Collected before, and a Sample Collected during the COVID-19 Lockdown.

BACKGROUND: Tools that assess all three components of 24 h movement guidelines (sleep, physical activity, and screen use) are scarce. Our objective was to use a newly developed Screen Time and Activity Recall (STAR-24) to demonstrate how this tool could be used to illustrate differences in time-use across the day between two independent samples of male adolescents collected before and during the COVID-19 lockdown. METHODS: Adolescent boys aged 15-18 years (n = 109) each completed the STAR-24 twice, n = 74 before lockdown and n = 35 during lockdown. RESULTS: During lockdown more than 50% of the sample reported gaming between 10 a.m. and 12 noon, transport was not reported as an activity, and activities of daily living spiked at mealtimes. Gaming and screen time were more prevalent in weekends than weekdays, with the highest prevalence of weekday screen use (before lockdown) occurring between 8 and 9 p.m. Differences in estimates of moderate-to-vigorous physical activity prior to and during lockdown (mean difference (95% CI); 21 (-9 to 51) min) and sleep (0.5 (-0.2 to 1.2) h) were small. Total and recreational screen time were higher during lockdown (2 h (0.7 to 3.3 h) and 48 min (-36 to 132 min), respectively). CONCLUSIONS: The STAR-24 holds promise as a single tool that assesses compliance with 24 h movement guidelines. This tool also allows clear illustration of how adolescent boys are using their time (instead of only providing summary measures), providing richer data to inform public health initiatives.

The Impact of Organised Sport, Physical Education and Active Commuting on Physical Activity in a Sample of New Zealand Adolescent Females.

BACKGROUND: The majority of adolescents do less physical activity than is recommended by the World Health Organization. Active commuting and participation in organised sport and/or physical education individually have been shown to increase physical activity in adolescents. However, how these domains impact physical activity both individually and in combination has yet to be investigated in a sample of New Zealand female adolescents from around the country. METHODS: Adolescent females aged 15-18 y (n = 111) were recruited from 13 schools across eight locations throughout New Zealand to participate in this cross-sectional study. Participants completed questions about active commuting, and participation in organised sport and physical education, before wearing an Actigraph GT3X (Actigraph, Pensacola, FL, USA) +24 h a day for seven consecutive days to determine time spent in total, MVPA and light physical activity. RESULTS: Active commuters accumulated 17 min/d (95% CI 8 to 26 min/d) more MVPA compared to those who did not. Those who participated in sport accumulated 45 min/d (95% CI 20 to 71 min/d) more light physical activity and 14 min/d (95% CI 5 to 23 min/d) more MVPA compared to those who did not. Participation in physical education did not seem to have a large impact on any component of physical activity. Participation in multiple domains of activity, e.g., active commuting and organised sport, was associated with higher accumulation of MVPA but not light activity. Conclusion Active commuting and sport both contribute a meaningful amount of daily MVPA. Sport participation has the potential to increase overall activity and displace sedentary behaviour. A combination of physical activity domains may be an important consideration when targeting ways to increase physical activity in adolescent females.

How Does Being Overweight Moderate Associations between Diet and Blood Pressure in Male Adolescents?

Diet is one of the strongest modifiable risk factors for hypertension. In this study, we described the associations between dietary factors and blood pressure; and explored how weight status moderated these associations in a sample of New Zealand male adolescents. We collected demographics information, anthropometric, blood pressure, and dietary data from 108 male adolescents (15-17 years old). Mixed effects and logistic regression models were used to estimate relationships between dietary variables, blood pressure, and hypertension. Moderation effects of overweight status on the relationship between hypertension and diet were explored through forest plots. One-third (36%) of the sample was classified as hypertensive. Fruit intake was related to significantly lower systolic (-2.4 mmHg, p = 0.005) and diastolic blood pressure (-3.9 mmHg, p = 0.001). Vegetable and milk intake was related to significantly lower diastolic blood pressure (-1.4 mmHg, p = 0.047) and (-2.2 mmHg, p = 0.003), respectively. In overweight participants, greater vegetable and milk, and lower meat intake appeared to reduce the odds of hypertension. Certain dietary factors may have more prominent effects on blood pressure depending on weight status.

Physical Activity, Sedentary Behaviour and Sleep, and Their Association with BMI in a Sample of Adolescent Females in New Zealand.

Despite activity guidelines moving towards a 24-h focus, we have a poor understanding of the 24-h activity patterns of adolescents. Therefore, this study aims to describe the 24-h activity patterns of a sample of adolescent females and investigate the association with body mass index (BMI). Adolescent females aged 15-18 years (n = 119) were recruited across 13 schools in 8 locations throughout New Zealand. Actigraph GT3X+ accelerometers were worn 24-h a day for seven days and the output was used to identify time spent in each 24-h component (sleep, sedentary, light-intensity physical activity and moderate-to-vigorous intensity physical activity). In a 24-h period, adolescent females spent approximately half their time sedentary, one third sleeping and the remainder in light-intensity physical activity (15%) and moderate-to-vigorous intensity physical activity (5%). Higher BMI z-scores were associated with 16 min more time spent in light-intensity physical activity. Additionally, those with higher BMI were less likely to meet the sleep and physical activity guidelines for this age group. Compliance with the moderate-to-vigorous intensity physical activity guidelines, sleep guidelines, or both, was low, especially in those classified as overweight or obese. The association between BMI and light activity warrants further investigation.

Dietary Intake Nutritional Status and Lifestyle of Adolescent Vegetarian and Nonvegetarian Girls in New Zealand (The SuNDiAL Project): Protocol for a Clustered, Cross-Sectional Survey.

BACKGROUND: Anecdotally, vegetarian eating patterns seem to be increasing in parallel with growing concerns about environmental sustainability. While this pattern of eating is widely believed to be associated with benefits for the planet and individual health, it may increase the risk of inadequate intakes and nutrient deficiency if not planned carefully. Adolescent girls may be particularly at risk, as they have increased requirements for nutrients such as iron, zinc, calcium, and vitamin B12 during growth and development. OBJECTIVE: The objective of the SuNDiAL Project (Survey of Nutrition, Dietary Assessment, and Lifestyles) is to compare the dietary intakes and habits, nutrition status, motivations, attitudes, and physical activity of a sample of vegetarian and nonvegetarian adolescent girls in New Zealand. METHODS: A clustered, cross-sectional, nationwide study of adolescents aged 15-18 years was conducted. Secondary schools were recruited throughout New Zealand, and pupils (n=290) were invited to participate in data collection in either the first (February to April) or third (August to October) school term of 2019 (New Zealand schools operate on a 4-term year). Sociodemographic and health information; vegetarian status; dietary habits; and attitudes, motivations, and beliefs regarding food choices were assessed via an online self-administered questionnaire. Dietary intakes were collected via two 24-hour diet recalls on nonconsecutive days and will be adjusted for within-person variation using the Multiple Source Method, to represent usual intakes. Nutrient adequacy will be assessed by the estimated average requirement cut-point method or probability approach as appropriate. Height and weight were measured, and blood and urine samples collected for micronutrient status assessment. Participants wore an accelerometer for 7 days to assess 24-hour activity patterns (time spent asleep, sedentary, or engagement in light-intensity or moderate-to-vigorous intensity physical activity). RESULTS: Recruitment and data collection were conducted in 2019. Data are currently being cleaned and analyzed, with publication of the main results anticipated at the end of 2020. CONCLUSIONS: The SuNDiAL Project will provide a meaningful and timely description of diet, nutrition status, and motivational factors associated with vegetarianism and identify any risks this pattern of eating may pose for female adolescents. The results of this study will support the development of targeted recommendations and interventions aimed at enhancing the health, growth, and development of adolescent girls. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12619000290190; https://tinyurl.com/yaumh278. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/17310.