Proceedings of the Nutrition Society最新文献

Dietary guidelines are increasingly promoting plant-based diets, limits on red meat consumption, and plant-based sources of protein for health and environmental reasons(1). It is unclear how the resulting food substitutions associate with insulin resistance, a risk factor for type 2 diabetes. Here, we modelled the replacement of red and processed meat with plant-based alternatives and the estimated effect on insulin sensitivity. We included 783 participants (55% female) from the Childhood Determinants of Adult Health (CDAH) study, a population-based cohort of Australians. In adulthood, diet was assessed at three time points using food frequency questionnaires: CDAH-1 (2004–06), CDAH-2 (2009–11), and CDAH-3 (2017–19). The median follow-up duration was 13 years. The cumulative average intake of each food group was calculated to reflect habitual consumption. Insulin sensitivity (%) was estimated from fasting glucose and insulin concentrations at CDAH-3 (aged 39–49 years) using homeostasis model assessment. Applying the partition model(2), we simulated the replacement of one food group with another by including both in the model simultaneously (e.g., red meat and legumes), along with potential confounders and energy intake. The difference between parameter estimates (i.e., regression coefficients and variances) and their covariance were used to estimate the “substitution” effect. We report the simulated percentage point change in log-transformed insulin sensitivity for a 1 serve/day lower intake of one food group with a 1 serve/day higher intake of another food group. Replacing red meat with a combination of plant-based alternatives was associated with higher insulin sensitivity (β = 0·10, 95% CI 0·04–0·16). Adjustment for waist circumference attenuated this association by 61·4%. On an individual basis, replacing red meat with legumes (β = 0·12, 95% CI 0·02–0·21), nuts and seeds (β = 0·15, 95% CI 0·06–0·23), or whole grains (β = 0·11, 95% CI 0·04–0·17) was likewise associated with higher insulin sensitivity. Point estimates were similar when replacing processed meat with plant-based alternatives, but more uncertain due to wide confidence intervals. Our modelling suggests that habitually replacing red meat, and possibly processed meat, with plant-based alternatives may associate with higher insulin sensitivity, and thus, a lower risk of type 2 diabetes. Abdominal adiposity was identified as a potentially important mediator in this relationship. In relation to insulin sensitivity, our findings support the recommendation to choose plant-based sources of protein at the expense of red meat consumption.

Utilising local and traditional foods in schools presents a significant opportunity within our region to ensure food and nutritional security, support local livelihoods by driving markets and employment opportunities, increasing food literacy, and help students to understand the role of, and develop a preference for these foods. School meals programs (SMP) are increasingly touted as a strategy for food system transformation(1), however, are not widely used in the Pacific Islands(2). Yet, there is increasing interest and momentum towards understanding school food and nutrition environments and the use of SMP in this region, especially with models that support and promote the integration of local, traditional climate-resilient, nutrient rich foods. When a large scale SMP may not be possible, other school food and nutrition activities can be utilised to support nutritious food choice. Evidence collected over the last five years provides information on the current situation, activities, and capacity for providing food in schools across the Pacific Islands (2,3,4). Activities across the region vary from national SMP to gardening programs, nutrition education, providing canteens/tuckshops and other ad hoc activities, for example events for World Food Day. Some activities have a requirement for the use of local food, while some prioritise local foods in gardening programs and work with local farmers. Recently it has been shown that youth are exposed to, and have access to significant amounts of ultra-processed foods (UPF) around schools(3). Mapping of the foods available to students within a 400m radius of 88 schools in Fiji found that sugar sweetened beverages were available in 80%, and lollies/confectionary in just over 60% of outlets. Fresh fruit was available in just over 20% of outlets, while fresh vegetables were available in less than 20% of outlets(3). While there are many challenges to providing local, traditional, nutritious foods in schools, including access to financial, human, and physical resources, stakeholders have told us that one of the most significant is how modernisation and colonisation of food systems have resulted in a preference for hyperpalatable UPF and how this makes it more challenging to incorporate local produce in a way that is accepted by students. This provides an opportunity to further explore and share ways to integrate local, traditional, climate-resilient, nutrient rich foods in schools to support children and adolescents to value, utilise, prefer, and advocate for these foods. There is a need to support the utilisation of traditional, local foods in schools by advocating for policy (at various levels, right from a school level upwards) that drives the use of these foods and creates more supportive school food environments.

Adequate energy intake (EI) is essential for adolescent athletes to support health, performance, and growth(1). Rowing is a physically demanding sport where intense training begins in adolescence. Research is needed to assess whether current EI is sufficient to support healthy physiological functions and training in adolescent rowers. The aim of this study was to evaluate the energy status (energy availability (EA) or energy balance (EB)) including EI and exercise energy expenditure (EEE) of adolescent rowers in New Zealand. A total of 35 rowers (23 females, 16.8yrs ± 1.9yrs; 12 males, 17.3yrs ± 1.6yrs) who had been rowing for at least one season participated. A bioimpedance analyser measured body composition in 11 participants (8 females, weight 63.0±7.0kg, fat free mass (FFM) 50.8 ± 6.5kg; 3 males, weight 78.5 ± 15.9kg, FFM 70.7 ± 12.2kg) enabling calculation of EA. Due to COVID-19 restrictions, the remaining 24 participants (15 females, 9 males) provided estimated body weight (74.7 ± 9.2kg) and EB was then used to evaluate energy status. All participants completed four days of food and training diaries, two ‘recovery’ and two ‘hard’ training days. EI was determined in FoodWorks10 software using the New Zealand Food Composition Database. For training, metabolic equivalent of tasks (MET)(2) were assigned using bodyweight, heart rate, and rating of perceived effort to estimate EEE. Paired sample t-tests or Wilcoxon Signed Rank test (non-parametric data) was used to determine differences between EI, EEE, EA, and EB on the high and low training days for each gender. Significance was set at p< 0.05. The average EI for females on hard and recovery days was 10837 ± 3304kJ and 10461 ± 2882kJ respectively, and for males was 15293 ± 3971kJ and 13319 ± 4943kJ, respectively. No significant differences were found between EI on hard vs. recovery days in both genders. Significant differences between average EEE on hard vs. recovery days were found in both genders (females, hard day 4609 ± 2446kJ, recovery day 3146 ± 1905kJ, p<0.001; males, hard day 6589 ± 1575kJ, recovery day 3326 ± 2890kJ, p = 0.001). EA on hard and recovery training days was classified as suboptimal at 142 ± 80kJ/FFMkg/day and 167 ± 79kJ/FFMkg/day respectively with no significant difference in EA between hard and recovery days (p = 0.092). Average EB on hard training days was −484 ± 4267kJ and on recovery training days was 572 ± 3265kJ, with no significant difference between training days (p = 0.177). Both genders showed no significant difference in EB between hard and recovery training days (females p = 0.221, males p = 0.978). The results suggest that adolescent rowers do not adjust their nutritional intake to match EEE. This may increase the risk of adolescent rowers presenting with suboptimal EB or EA, with females being at a greater risk than males.

Weight loss or fad diets are often promoted for rapid weight loss and by unqualified individuals and celebrities. There is sometimes limited information around the nutritional adequacy of the diet. Some diets require fasting, some modify macronutrient composition, and some restrict food groups, such as dairy foods, resulting in suboptimal intake of nutrients like calcium, potentially leading to nutrient deficiencies and disease such as osteoporosis if followed long-term. We assessed the total dairy food and calcium content of five popular weight loss diets (Intermittent Fasting, Ketogenic, Optifast, Paleolithic, 8 Weeks to Wow; 8WW), and two government recommended healthy eating principles (Australian Guide to Healthy Eating; AGHE, and Mediterranean diet; MedDiet, for weight loss). Meal plans from each diet were analysed using Foodworks Dietary Software and compared with government recommendations and dietary reference values (DRV) in Australia, the United States and Ireland to give the percentage of the recommended intake of dairy food and calcium, met by each diet(1). Intermittent Fasting, Ketogenic and AGHE provided the most serves of dairy foods with 2.8, 2.3 and 2.2 serves/d, respectively, whilst 8WW, MedDiet, and Optifast provided 1.4, 1.3 and 1 serve/d each, respectively, and Paleolithic 0.02 serves/d. None of the dietary patterns met all government recommendations for dairy serves. Milk was the most common source of dairy food in all dietary patterns except for Ketogenic (cheese), MedDiet (yoghurt) and Paleolithic. The Ketogenic diet provided the highest calcium content (1293mg/d), followed by Intermittent Fasting (1230mg/d) and Optifast (1212mg/d). Non-dairy sources contributed to 93% of the calcium content (385mg/d) of the Paleolithic diet, 70% for Optifast and 61% in the MedDiet (631mg/d). None of the dietary pattens met all dietary reference values for calcium. There are no universal dietary recommendations for dairy foods or calcium, making cross country comparisons of dietary recommendations difficult. Only the Intermittent Fasting diet met the dietary recommendations in Australia for dairy serves for males 19-70 and females 19-50 years. None of the other diets met any recommendation for Australia, the US and Ireland. Most dietary patterns met the estimated average requirement for age and gender, for calcium for Australia, the US and Ireland, apart from the Paleolithic diet which eliminates dairy foods and the MedDiet which is naturally low in dairy foods. These data indicate that several popular weight-loss diets do not meet dietary recommendations for dairy foods or calcium. Therefore, when considering a weight loss diet or dietary pattern, it is crucial to consider the nutritional adequacy, to ensure macro and micronutrient requirements are met for health and avoidance of nutritional deficiencies, particularly if followed long-term.

A majority of Australians consume a limited range of different dietary fibres and insufficient total dietary fibre(1). This contributes to low intestinal microbial diversity and impaired microbial function, such as capability in producing beneficial metabolites like short-chain fatty acids (SCFA). This diet-induced dysbiosis is associated with poor gastrointestinal health and a broad range of non-communicable diseases(2). Our study aimed to determine whether one dietary change, substitution of white bread with a high fibre bread improves faecal microbial diversity and butyrate-producing capability. Twenty-six healthy adults completed a randomised, cross-over, single-blinded intervention. Over the two intervention phases separated with a 4-wk washout, participants consumed either 3 slices of a high fibre bread (Prebiotic Cape Seed Loaf with BARLEYmax®) or control white bread as part of the usual diet, each for 2 weeks. At the beginning and end of each intervention period, participants completed a 24-h diet recall, a gut symptoms rating questionnaire and provided a faecal sample for microbiome analysis. The composition of faecal microbiome was characterised using 16S rRNA amplicon sequencing (V3-V4) and a marker of butyrate synthesis capability, the faecal content of butyryl-CoA:acetate CoA-transferase (BCoAT) gene was assessed using Real-time PCR. The high fibre bread intervention increased the servings of whole grain from 1.5 to 4 per day and increased total dietary fibre intake to 40 g/d which was double the amount of fibre consumed by participants at baseline or during the white bread intervention. Compared to white bread, the high fibre bread increased richness and evenness (Shannon, p = 0.014) of the gut microbiota and increased the relative abundance of SCFA producing taxa Lachnospiracae ND3007 group (p <0.001, FDR = 0.019). In addition, the high-fibre bread tended to increase relative abundance of butyrate-producing genus Roseburia, and microbial BCoAT gene content compared to white bread. In conclusion, the substitution of white bread with high-fibre bread improved the diversity of gut microbiota, specific microbes involved in SCFA production and may enhance the butyrate production capability of gut microbiota in healthy adults.

Brown Buttabean Motivation (BBM) is a Māori and Pacific-driven community-based organisation operating in Tāmaki Makaurau (Auckland) and Tokoroa. It provides free community exercise bootcamps and other social and health support programs. BBM’s foundational mission was to reduce, among Māori and Pacific people, the prevalence of obesity in Auckland through exercise and nutrition programs.1 This study aimed to understand participants’ engagement with BBM, and the meaning it has had in their lives, with a focus on nutrition. Combining Pacific Fonofale and Te Whare Tapa Wha frameworks, this was a process evaluation to understand the impact of BBM’s services on the community using qualitative methods and a systems analysis to identify program sustainability and improvement. Semi-structured interviews explored the benefits and values of engagement with BBM. Followed by cognitive mapping interviews (CMI) and group model building (GMB) to identify the motivations and challenges of sustained engagement. Participants described holistic health benefits and impacts on community wellbeing. BBM responds to inequitable nutrition contexts, through its FoodShare (food bank), community kitchen, and BBM Kai (nutrition literacy). Engagement changed family nutrition patterns, and benefits included healthier spending habits, and addressing food insecurity. Social inclusiveness represented the Fonofale foundation (family) and the roof (culture) was described as ethnic cultural practices and BBM culture. Nutrition was not highlighted by BBM participants in CMI or GMB activities. However, participants suggested BBM increase nutrition initiatives to enable all members to improve their health journeys. BBM was seen as not just an exercise program but their own and their family’s new way of life, that health was a journey, not a destination. Moreover, although participants mentioned nutrition and health benefits, there was an overwhelming understanding that the values of BBM, Pacific culture, and social collectivism were the drivers of engagement, motivating healthier practices. BBM could leverage existing strengths by incorporating nutrition-enabling initiatives that are achieved collectively. Opportunities for systematic intervention will be presented.