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    Investigating the impact of αs1-casein genetic variants on sheep milk composition, physico-chemical properties, rennet gelation properties and digestion behavior : a thesis presented in partial fulfilment of the requirements for the degree of Master of Food Technology at Massey University, Palmerston North, New Zealand. EMBARGOED until 18th December 2025.
    (Massey University, 2023) Chiang, Kuan Yu
    Sheep milk is an important dietary resource in various regions across the world, including the Middle East, Europe, and certain developing countries. The unique composition of sheep milk, with high levels of protein, fat, and essential vitamins, makes it a valuable source of nutrition. Furthermore, the genetic polymorphism of αs1-casein in sheep milk has recently gained attention due to the potential influence on sheep milk properties and dairy production. In this study, the genetic variations in αs1-casein and their effects on the physicochemical properties, composition, rennet gelation properties and digestion behavior of sheep milk were investigated and discussed. The genetic polymorphism of as₁-casein among 39 sheep milk samples were analyzed. Four αs₁-casein phenotypes were identified: AC, BB, BC, and CC and eight sheep milk samples which produced from individual ewes were selected for further investigation. While the fat content remained consistent among the samples, there were significant differences in sheep milk protein and lactose content. Among the selected eight samples, sample 192574 exhibiting the highest protein content and lowest lactose content. In addition, differences were observed in the proportions of major caseins and whey proteins in sheep milk. The mineral content, specifically magnesium, potassium, phosphorus, and sodium, showed variations between samples, and κ-casein, potassium, and phosphorus content seem appeared to be influenced by αs₁-casein phenotypes. The result showed that BB αs₁-casein phenotypes had the highest proportion of κ-casein, while AC αs₁-casein phenotypes had the highest potassium and phosphorus content. The physico-chemical properties including pH, casein micelle size, fat globule size, ethanol stability, heat stability and ionic calcium content were examined. The results showed that, apart from casein micelle size and fat globule size, most physicochemical properties of sheep milk exhibited significant differences among the eight samples. The rennet gelation time, final G', and final tan δ of the sheep milk samples were also examined. Although there were no significant differences in these parameters between the eight selected samples, variations emerged when considering the sampling time, with larger variations in samples from March compared to those from February. Seasonality was found to have a significant impact on the physico-chemical and rennet gelation properties of sheep milk, particularly towards the end of the season. However, no significant differences were observed in the physico-chemical and rennet gelation properties with respect to αs₁-casein phenotypes, it requires for a larger sample size to validate any potential influences in future research. Furthermore, in vitro dynamic gastric digestion was carried out to investigate the digestion behavior of sheep milk. Previous studies primarily focused on bovine milk, and limited information was available on sheep milk digestion behavior, especially concerning the effects of genetic polymorphisms. In this study, eight sheep milk samples from ewes with different αs₁-casein phenotypes were subjected to 20 min in vitro dynamic gastric digestion and three selected samples with different αs₁-casein phenotypes were subjected to 240 min digestion experiment. The curds formed at 240 minutes during gastric digestion displayed a denser and smaller structure, lower dry and wet weights, lower moisture content, and higher G* value compared to the 20-minute digestion curds. The pH profiles of the digesta of the selected three samples did not exhibit significant differences, despite variations in the initial pH values. Furthermore, the SDS-page profiles of the samples revealed that sample 192574 had the most distinct protein hydrolysis level. The distinct digestion behavior of this sample may be attributed to its significantly lower pH and higher κ-casein content compared to the other samples. However, the result showed that αs₁- casein genetic variation had no significant impact on digestion behavior. In conclusion, this research sheds light on the genetic polymorphism of αs₁-casein in sheep milk and its potential effects on composition, physico-chemical properties, rennet gelation properties and digestion behavior. These findings can inform future efforts to improve milk quality and dairy production, as well as enhance the understanding of the complex factors influencing sheep milk properties.
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    Macronutrient intakes of adolescent rowers for growth, development and sports performance : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Nutrition and Dietetics at Massey University, Albany, New Zealand
    (Massey University, 2023) Watts, Samantha
    Introduction: Dietary intake plays a central role in athletic performance in competitive rowing (Cornford & Metcalfe, 2019). During moderate training, it is recommended that adolescent athletes aim for 5.0-7.0¹ of carbohydrates, 1.3-1.8¹ of protein, and 20-35% energy from fat (Desbrow et al., 2014). Suboptimal nutrition within the adolescent rowing population may negatively impact growth and development, rowing performance, professional athlete development and career longevity. Previous research has indicated that suboptimal carbohydrate intake is a common issue in rowing (Baranauskas et al., 2014). The quality of dietary intake in adolescent rowers has seldom been explored. This study aimed to examine the dietary intake of adolescent rowers in New Zealand and compare it with nutritional guidelines for normal growth, development, and sports performance. Methods: A cross-sectional study design involved data collection on two hard training days and two recovery days from rowers aged 14-21 years from around New Zealand. During the four 24-hour collection periods participants recorded food intake, training duration and intensity. The food records were verified for accuracy, and dietary data was entered into Foodworks software for nutritional analysis. IBM SPSS software was used to calculate the mean intake and standard deviations for carbohydrate, protein, and dietary fat. Independent t-tests were used to compare the carbohydrate and protein intakes between males and females. Results: Of the initial 40 participants, 35 fully (females n=23, 16.8±1.9 years; males n=12, 17.3±1.6 years) completed the study. Participants consumed 319±116 g (4.5±1.7¹.day-¹) of carbohydrates, 121±56 g (1.7±0.7¹.day-¹) of protein and 113±46 g (1.6±0.6¹.day-¹) of fat per day. Females consumed 290±80 g (4.4±1.3¹.day-¹) of carbohydrates and males consumed 400±78 g (5.0±1.4¹.day-¹) per day, with no significant difference between males and females intake per kilogram of bodyweight per day (p=0.165). Minimum carbohydrate levels of 5.0¹ per day were only achieved by seven females (30.4%) and four (33.3%) males. Females consumed significantly less protein per day, 106±38 g (1.6±0.6¹.day-¹), in comparison to males who consumed 164±46 g (2.0±0.5¹.day-¹) per day (p=0.04). Fourteen females (60.9%) and ten males (83.3%) consumed more than the minimum requirement of 1.3¹ of protein per day. Conclusion: The findings suggest that two out of three adolescent rowers in New Zealand fail to reach the minimum recommendation for carbohydrate intake (Desbrow et al., 2014), and males more readily meet the recommended intakes of protein when compared to females. Nutrition education for adolescent rowers in New Zealand should emphasise adequate carbohydrate and protein intakes that meet sports nutrition guidelines in order to support normal growth, development and optimised performance for these athletes.
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    Validation and reproducibility of an iodine and selenium specific food frequency questionnaire in breastfeeding women : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Nutrition and Dietetics at Massey University, Albany, New Zealand
    (Massey University, 2023) Bertasius, Charlotte
    Backgrounds: New Zealand has poor levels of iodine and selenium in its food sources. During lactation, women have increased selenium and iodine requirements, as their breastfeeding infant relies on their intake, putting them at increased risk of deficiency. Thyroid function is impacted by iodine and selenium status, and if these nutrients are low can cause consequences for the mother and breastfed infant. Dietary assessment methods, such as a Food Frequency Questionnaire (FFQ), can be utilised to assess nutrient intake, and validating an FFQ shows that the questionnaire can be used on the intended population to predict nutrient intake. To the best of our knowledge, New Zealand currently does not have a valid iodine and selenium specific FFQ for breastfeeding women. Due to this population risk with iodine and selenium, it is justified to test the validity and reproducibility of this FFQ on breastfeeding women in New Zealand. Aim: The aim of this study is to assess the validity and reproducibility of an iodine and selenium specific Food Frequency Questionnaire for breastfeeding women living in New Zealand. Methods: As part of the Mother and Infant Nutrition Investigation study (MINI), data was collected from breastfeeding mothers from three months to 12 months postpartum (PP). Participants (n = 87) were administered an iodine and selenium specific FFQ at three months and a four-day diet diary (4DDD). To assess reproducibility the FFQ was readministered at 12 months PP (FFQ2). FFQ1 was validated via 4DDD and selected biomarkers (urinary and breastmilk iodine concentrations and plasma selenium); statistical analysis was used, including Wilcoxon signed ranked test, Spearman’s correlation, cross-classifications, weighted kappa statistics, Bland Altman plots, the same statistical analysis carried out to assess reproducibility between FFQ1 and FFQ2. Results: For the validation, the correlation observed ranged from 0.317 (selenium) to 0.532 (total iodine) between the FFQ and 4DDD and for FFQ to EIB, 0.146 (selenium) and 0.155 (total iodine). Cross-classifications majority of the nutrient groups were >50% correctly classified (32.9% (selenium) to 71.6% (iodine food only)) when comparing the FFQ to 4DDD. Most of the groups were <10% misclassified (1.37% (iodine and salt) to 11.0% (selenium)). For the FFQ to EIB, the correctly classified participants were 50% (iodine) and 73.1% (selenium), and the grossly misclassified participants were 16.35% (iodine) and 3.4% (selenium). For FFQ to 4DDD, the weighted kappa values showed poor agreement (k<0.21) for two groups and fair agreement (k 0.21-0.41) for three groups. For EIB, the weighted kappa showed poor agreement (k<0.21) for four groups and fair agreement (k 0.21-0.41) for one. The Bland-Altman plots showed fair agreement for the difference between FFQ1 to 4DDD or EIB. For reproducibility, the correlation between FFQ1 and FFQ2 was 0.625 (iodine) and 0.429 (selenium). Cross-classification for correctly classified participants was >50% for iodine; for selenium and iodine, <10% were grossly misclassified. The weight kappa value showed poor agreement (k0.21) for both iodine and selenium. Conclusion: The FFQ showed reasonable validity when assessing iodine and selenium intake using the FFQ for breastfeeding women in New Zealand and showed good reproducibility for iodine and selenium. This FFQ could be used in future research on this population and could be used in primary care as a convenient way to assess iodine and selenium intake for breastfeeding women in New Zealand.
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    Prevalence and frequency of menstrual cycle symptoms in exercising females and their perceived impact on exercise performance : a thesis presented in partial fulfilment of the requirements for the degree of Master of Health Science in Sport and Exercise, Massey University, Albany, New Zealand
    (Massey University, 2023) Wilton, Hannah
    Background: Menstrual cycle symptoms (MCS), experienced by up to 93% of females, can negatively impact quality of life. Yet research investigating the impact of these symptoms on exercise/sport performance is still in its infancy and is largely focused on the elite athletic population. Furthermore, many studies do not account for the fact that 43% - 57% of females do not have a natural menstrual cycle (MC) and are using hormonal contraception (HC). Further investigation is needed to examine the impact of the potential perceived negative effects associated with MCS and HC use on physical performance in exercising females. Objectives: Identify and compare the prevalence and frequency of MCS in naturally menstruating (NM) females and females using HC. Identify and compare the perceived impact of MCS or HC side effects on exercise/sport performance and participation in NM females and females using HC. Methods: Two hundred exercising females (age 26 ± 6 years) participated in this study. Participants completed an online questionnaire which was an amalgamation of four independent validated surveys, including, the International Physical Activity Questionnaire – short form (IPAQ) to assess physical activity levels, the Reproductive Status Questionnaire for Menstrual Cycle Studies to assess MC status, the STRAVA x FitrWomen Survey to evaluate prevalence and frequency of MCS and their effect on exercise/sport participation, and the Exercise and Menstruation in Australia Questionnaire to assess perceived impact on exercise/sport performance. After data cleaning to remove incomplete responses, 182 participants were included in the final analysis. For each participant, total number, and frequency of MCS were added based on a Likert scale to receive a menstrual cycle index (MSi) score. Correlations between MSi and likelihood of missing exercise sessions and likelihood of reporting positive, neutral, or negative training outcomes were assessed. Results: Participants were 54.4% NM and 45.6% HC users, with the oral contraceptive pill (OCP) being the most used (23.6%) form of HC. The most prevalent MCS for both groups were, changes in mood/increased irritability, bloating/increased gas, stomach cramps, cravings/increased appetite, and increased tiredness/fatigue. MSi score did not differ significantly between NM females and HC users (p = 0.435). MSi score was weak - moderately correlated to and increased likelihood of missing training in both NM females (p < 0.001) to report negative training outcomes than HC users. Whereas HC users were more likely (P < 0.001) to report no changes to their training performance. Conclusion: Results from this study demonstrate that MCS are very common in exercising females, with no difference in prevalence or frequency between NM females and HC users. The large prevalence of MCS and associations to negative training outcomes and missing training sessions would suggest greater education and awareness on managing and reducing the risk of MCS is imperative to improve the wellbeing and exercise performance of females.
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    Investigating the eating behaviours of free-living low-carbohydrate diets users in New Zealand : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Nutrition and Dietetics, Massey University, Albany, New Zealand
    (Massey University, 2024) Nunn, Chloe
    Background: Many individuals adopt a low-carbohydrate (low-CHO) diet as a weight management approach. Eating behaviours are a crucial determinant of dietary intake and health, however, their relation to low-CHO diet users has scarcely been assessed. Aim: This study aimed to investigate the body compositions, dietary intakes, and eating behaviours of free-living, self-reported low-CHO diet users in NZ and how they differed between CHO intake groups. Methods: This cross-sectional study recruited men and women aged 20-45 years following a low-CHO diet for at least four months. Participants completed a health and demographics questionnaire, the Three-Factor Eating Questionnaire (TFEQ), a 4-day weighed dietary record, and provided anthropometric measurements. Participants were grouped into three CHO intake ranges defined as moderately low (ML) (>100 and <150 g/day) (n=10), low (L) (≥50 and <100 g/day) (n=20), and very-low (VL) (<50 g/day of CHO) (n=39). Results: Sixty-nine individuals with a mean age of 35 years participated in this study. Their mean macronutrient intakes as a contribution to total energy were 12.5 ± 8.28% for CHO, 58 ± 11.3% for total fat, 22.6 ± 6.98% for saturated fatty acids (SFA), and 24.5 (23.3-25.9) % for protein. Total fat and SFA (%EI) increased as CHO intake decreased, while protein intake was similar in each CHO group. They had a mean body fat percentage (BF%) of 27.9 ± 9.9% and a median muscle mass of 28.0 [25.2-33.2] kg. Body composition was similar in each CHO group. Overall, participants showed high restraint, low rigid and flexible restraint, low disinhibition, low habitual, situational, and emotional disinhibition, low hunger, and low internal and external hunger. TFEQ scores did not differ significantly between CHO groups. Restraint was positively associated with CHO (%EI) (r = 0.34, p = <0.01) and inversely associated with total fat (r = -0.35, p = <0.01) and SFA (%EI) (r = -0.31, p = 0.01). CHO intake (%EI) was positively correlated with rigid restraint (r = 0.27, p = <0.01) and flexible restraint (r = 0.34, p = <0.01). Restraint correlated with BF% (r = 0.28, p = 0.02), and each increasing restraint score predicted a 0.6% increase in BF%. As diet duration increased, BMI (r = -0.27, p = 0.03), WC (r = -0.28, p = 0.03), and habitual disinhibition (r = - 0.27, p = 0.03) decreased. Conclusions: Our findings suggest that low-CHO diet users exhibit high dietary restraint, low disinhibition, and low hunger. Restraint may increase as CHO intake increases and fat intake decreases. BF% was accompanied by high restraint. It is important to consider the associations eating behaviours can have with dietary intake and body composition in low-CHO diets in determining the suitability of such a diet.
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    Orchard yield estimation using multi-angle image processing : submitted to the School of Food and Advanced Technology in partial fulfilment of the requirements for the degree of Master of Engineering in Mechatronics at Massey University, Auckland
    (Massey University, 2023) Ripa, Leon
    The rise of autonomous robots and deep learning techniques in recent times has sparked a surge in complex multi robot system (MRS), leveraging these technologies to handle intricate tasks and complement human labour. As the agricultural landscape has evolved from labour intensive, small-scale farming to vast macro-managed expanses, precision agriculture (PA) has emerged to address the challenge. PA offers farmers micro-scale insights into their farms, enabling precise knowledge of pest presence, crop growth variations, and expected yields. For kiwi fruit farmers in New Zealand—spanning over 15,500 hectares and yielding more than 11.65 thousand trays per season—issues persist due to the absence of a mechanical harvesting solution. The inability to accurately estimate yields results in potential profitability concerns, often leading to over, or underemployment during fruit picking. Furthermore, the spread of viruses and diseases poses significant challenges, compelling the need to minimize human intervention and activity under kiwi orchards. Integrating PA techniques not only facilitates fruit counting but also provides crucial insights into fruit density, aiding in identifying underperforming areas for better farm management and potential yield enhancement. This thesis introduces current methods used for orchard yield estimation and presents a novel approach tailored for estimating yields in kiwi fruit orchards. It discusses established solutions for similar agricultural challenges and explores their integration to devise the most effective method for estimating kiwi orchard yields. The proposed solution employs object detection through a convolutional neural network to identify, track, and count kiwi fruits. This is facilitated by images captured by a hexa-drone UAV flown beneath kiwi orchards, ensuring smoother camera capture for increased accuracy in object detection throughout the orchard. This data not only enables farmers to estimate current kiwi production but also aids in identifying sections of orchards that may be overperforming or underperforming.
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    The effects of CYP1A2 gene polymorphisms on caffeine pharmacokinetics and exercise performance : a thesis presented in the partial fulfilment of the requirements for the degree of Master of Science in Nutrition and Dietetics, Massey University, Albany, New Zealand
    (Massey University, 2024) Masters, Chloe
    Background: Caffeine is one of the most popular psychoactive stimulants consumed globally. The CYP1A2 gene encodes the cytochrome P450 1A2 enzyme, found in the liver, which is predominantly responsible (~95%) for caffeine metabolism in the body. A single nucleotide polymorphism (SNP) in the non-coding region of the CYP1A2 gene (CYP1A2; rs762551) induces different expression levels of the enzyme, influencing the clearance rate of caffeine from the body. There are equivocal results as to whether the CYP1A2 genotype is a determinant of exercise performance following supplementation with caffeine. This lack of consensus may be due to differences in trial designs, including mixed exercise modes, and solely male, or mixed sex participant cohorts with most studies using a caffeine dose of between 3-6 mg·kg-¹, and commencing exercise 60-min following caffeine ingestion. Purpose: This research aimed to determine if 6 mg·kg-¹ caffeine ingested 60-min prior to commencing exercise impacts performance, and to identify if the CYP1A2 gene, and consequent caffeine metabolism rates, has a role in improving exercise performance following caffeine consumption. Methods: Thirty-eight healthy, recreationally active, male athletes were recruited for this study. All participants were classified as moderate caffeine users. Participants attended one familiarisation session, where their body composition was measured, practiced a 1-km run or 40-km cycle, and provided saliva samples for genotyping to identify their specific CYP1A2 SNP. Two follow up sessions were undertaken one week apart, with participants completing either a 10-km run or 40- km cycle following the ingestion of an anhydrous caffeine capsule (6 mg·kg-¹) or placebo (maltodextrin) following randomised, placebo-controlled double-blind protocols. Blood sampling was undertaken before, during and following exercise in the two exercise trials to measure plasma caffeine, paraxanthine and theophylline concentrations. Results: Caffeine supplementation improved exercise performance by 1.8% (p=0.05; ηp²=0.12), with greater improvements in performance seen in the second half of exercise (2.4%; p=0.02; ηp²=0.16) in comparison with the first half (1.2%). Twenty-four of the 34 participants whose data were used to analyse time to completion, showed an improvement in exercise performance with caffeine ingestion. Heart rate was higher in participants following caffeine ingestion compared to placebo (p=0.02; ηp²=0.15). Genotyping showed 50% of participants were homozygous AA allele carriers and 50% heterozygous AC allele carriers. No participants carried the CC allele polymorphism. Plasma caffeine concentrations were higher in AA allele carriers than AC allele carriers (p=0.05; ηp²=0.207). No gene-treatment interaction effects were observed in time to completion, heart rate (HR) or plasma concentrations of paraxanthine or theophylline. A significantly higher total sum of plasma caffeine was observed in the area under the concentration time curve (AUC) in AA allele carriers compared with AC allele carriers (p=0.01). Conclusion: Ingesting a dose of 6 mg·kg-¹ caffeine 60 min prior to exercise is likely to improve performance in endurance activities in recreationally trained males. Plasma caffeine concentrations were significantly higher in AA allele carriers compared to AC allele carriers, though no gene caffeine interaction was observed in time to completion, therefore the role of CYP1A2 gene polymorphisms and caffeine consumption in determining enhancements in exercise performance remains unclear.
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    The relationship between the motivation of health for being vegan and the intake of key nutrients and nutritional status in individuals following a vegan diet : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Nutrition and Dietetics, Massey University, Albany, New Zealand
    (Massey University, 2024) Pearce, Rebecca
    Background: The fundamental principle of veganism is to avoid all possible animal exploitation and therefore, animal ethics has always been a primary motivator. Nowadays, the environment and health are becoming increasingly common motivators for veganism. Omission of all animal products leads to dietary exclusion of vitamin B12, limited intake of omega-3 fatty acids, specifically EPA and DHA, and intake of low bioavailable iron sources. It is unknown whether greater health motivation leads to enhanced intake and status of nutrients. Objectives: To describe the importance placed on three motivations for following a vegan diet, to investigate the role of health motivation on dietary intake of vitamin B12, iron and the nutritional status of omega-3 fatty acids, vitamin B12, and iron, as well as investigate the role of health motivation on use of vitamin B12, iron and omega-3 supplementation. Methods: This cross-sectional, observational study recruited participants, who had followed a vegan diet for minimum 2 years. Demographics were obtained from questionnaires. Motivation type was determined using the validated vegetarian eating motives inventory (VEMI) – participants scored the importance of animal ethic, environment and health. Dietary intakes of vitamin B12 and iron, were calculated from a 4-day food diary and assessed against Estimated Average Requirement (EAR). Blood samples were taken to determine status of vitamin B12, haemoglobin, serum ferritin, and omega-3 index. Results: The study was completed by 212 participants, of whom 73% were female, and the mean (SD) age was 39.43 years (12.41). Animal ethics was a very important motivator for 83.5% of participants, compared to the environment (71.7%), and health (53.3%). Participants motivated the greatest by health had significantly higher intake of iron (p = 0.032) and lower intake of vitamin B12 (p = 0.006) after adjusting for energy intake. No relationship was found between health motivation and omega-3 index. Participants used omega-3 fatty acid, iron and B12 supplementation regardless of level of health motivation. Mean haemoglobin serum concentration was adequate (154.31g.L), as was mean serum ferritin (41.62µg.L), and mean serum vitamin B12 (316.54pmol.L). The mean omega-3 index was 3.15%, with no participants having a cardioprotective score of >8%. Conclusion: The motivation of health appears to influence intake of iron and vitamin B12. Vitamin B12 status within normal range despite not meeting the EAR and limited vegan sources, indicates the use and importance of supplementation. Iron status shows large consumption of iron rich foods to overcome bioavailability issues. The omega-3 index reveals low cardioprotective omega-3 fatty acid intake.
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    Investigation of the food environment surrounding primary schools in New Zealand : a thesis presented in partial fulfilment of the requirements of the degree of Master of Science in Nutrition and Dietetics
    (Massey University, 2024) Nicholls, Kate
    Background: Childhood obesity is a prominent issue in New Zealand (NZ). Children's daily exposure to their food environment significantly influences their health, dietary patterns, and preferences. With children spending a substantial portion of their time on school grounds, the quality of the food environment within and around schools emerges as a crucial factor. Efforts have been made to enhance the food environment within schools. However, limited action has been taken to improve the food environment surrounding schools. Therefore, a comprehensive understanding of the food environment surrounding schools, encompassing both advertisements and stores and exploring correlations with internal food environments, is needed. This knowledge is paramount for informing policymakers and catalysing targeted actions to address childhood obesity comprehensively. Aims: To investigate food and beverage advertising and stores surrounding NZ primary schools and to explore correlations between the external food environment (food and beverage advertisements) and the internal food environment (Healthy Active Learning food menu and policy data) for these schools. Methods: Food and beverage advertisements (n=479) and stores (n=215) within 800 m of 18 primary schools were collected via Google Street View in August 2023. Advertisement and store characteristics were compared across different school deciles (low, medium and high). To determine the healthiness of the advisement, food and beverage advertisements were separated into ‘core’ and ‘non-core’ depending on whether they are considered part of the everyday diet. Results: ‘Non-core’ advertisements (n=426, 89.0%) outnumbered ‘core’ advertisements (n=53, 11.0%), with sugar-sweetened beverages (n=192, 40.1%) the most common category, and Coca-Cola the most common brand (n=158, 33.0%). The majority of advertisements were found near low (n=406, 43.0%) and medium (n=208, 43.4%) decile schools, with low decile schools having more nearby (0-400 m) advertisements (n=111, 57.5%). Advisement characteristics varied by school decile including; distance from school, brand and secondary marketing classifications. The number of advertisements strongly correlated with the number of stores (rs=0.879, n=18, p<0.001), with most advertisements (97.1%) located on food stores. The most common food and beverage stores near schools were local fast-food restaurants (44.7%) and convenience stores (24.2%). Low and medium-decile schools have more convenience stores, fast food outlets and bakeries within 800 m, while high-decile schools have more supermarkets and cafés. Conclusions: ‘Non-core’ food and beverage advertising, fast food stores, and convenience stores are highly prevalent surrounding primary schools, particularly surrounding low and medium-decile schools.
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    The development of a questionnaire for the assessment of menstrual health literacy amongst active females : a thesis present in partial fulfilment of the requirements for the degree of Master of Science in Nutrition and Dietetics, Massey University, Auckland, New Zealand
    (Massey University, 2023) Fletcher, Danielle
    Background: Poor menstrual health literacy (MHL) is a factor that contributes to females not seeking medical help for abnormal menstrual symptoms that may impact their mental, social, and physical health (Garside et al., 2008). Few studies have focused on testing baseline functional knowledge of the menstrual cycle (MC) outside the context of pregnancy and menopause. The primary objective of this study was to investigate MHL levels of physically active females residing in New Zealand using a developed validated questionnaire. A secondary objective was to understand where females get their MC information from, what sources they consider to be trustworthy and what MC information they would like to know more about. Methods: A MC knowledge questionnaire was developed by the research team (n=3), and reviewed by academics (n=4), medical experts (n=4), sporting organisation staff (n=5), and target population (n=10) to ensure content validity. Active females (n=203) between the ages of 16-40 years completed an online questionnaire. The questionnaire included a total of 25 knowledge questions and was split into four categories: menstrual cycle (Q=9), menstruation (Q=6), symptoms (Q=4), and health outcomes (Q=6). All correct options were coded as ‘1’ and incorrect options were coded as ‘0’. A total score of 44 was possible. Responses (single and multiple answer multi-choice questions) were analysed using descriptive statistics which were presented as mean, SD and frequency (%). Results: The overall knowledge score was 51.8% (22.8± 3.4). The highest knowledge scores were noted for symptoms (80.5%), followed by menstruation (79.8%), and the menstrual cycle (64.2%). Females scored poorly when asked about health outcomes related to the MC (20.4%). The majority of the participants (n=123, 61.5%) identified the internet as their main source of MC information. Friends (n=82, 41%), school sex education (n=73, 36.5%) and social media (n=73, 36.5%) were the next most common sources of MC information. Participants considered the most trustworthy sources of information to be doctors/general practitioners (n= 96, 48%) and healthcare professionals (n=70, 35%). The most common topics that females wanted to know more about were diet and the MC (n=115, 57.5%), training and the MC (n=115, 57.5%), MC tracking (n=78, 39%), MC and mood (n=75, 37.5%) and Relative Energy Deficiency in sport/Low Energy Availability/Female Athlete Triad (n=71, 35.5%). Conclusion: Overall functional knowledge levels of the MC and associated health outcomes is low in active females in New Zealand. Healthcare professionals and doctors are considered the most trustworthy sources of information; however, they are not the most common sources of information that females will engage with. Developing online educational resources on the MC, associated health outcomes and lifestyle factors (diet, physical activity) with medical and healthcare professionals may be considered in future female health education.