Iron intakes of Australian infants and toddlers: findings from the Melbourne Infant Feeding, Activity and Nutrition Trial (InFANT) Program

Fe deficiency remains the most common nutritional deficiency worldwide and young children are at particular risk. Preventative food-based strategies require knowledge of current intakes, sources of Fe, and factors associated with low Fe intakes; yet few data are available for Australian children under 2 years. This study’s objectives were to determine intakes and food sources of Fe for Australian infants and toddlers and identify non-dietary factors associated with Fe intake. Dietary, anthropometric and socio-demographic data from the Melbourne Infant Feeding, Activity and Nutrition Trial Program were analysed for 485 infants (mean age: 9·1 (sd 1·2) months) and 423 toddlers (mean age: 19·6 (sd 2·6) months) and their mothers. Dietary intakes were assessed via 24-h recalls over 3 non-consecutive days. Prevalence of inadequate Fe intake was estimated using the full probability approach. Associations between potential non-dietary predictors (sex, breast-feeding status, age when introduced to solid foods, maternal age, maternal education, maternal employment status and mother’s country of birth) and Fe intakes were assessed using linear regression. Mean Fe intakes were 9·1 (sd 4·3) mg/d for infants and 6·6 (sd 2·4) mg/d for toddlers. Our results showed that 32·6 % of infants and 18·6 % of toddlers had inadequate Fe intake. Main food sources of Fe were Fe-fortified infant formula and cereals for infants and toddlers, respectively. Female sex and current breast-feeding were negatively associated with infant Fe intakes. Introduction to solid foods at or later than 6 months was negatively associated with Fe intake in toddlers. These data may facilitate food-based interventions to improve Australian children’s Fe intake levels.

Infant feeding websites and apps: a systematic assessment of quality and content

Background: Internet websites and smartphone apps have become a popular resource to guide parents in their children’s feeding and nutrition. Given the diverse range of websites and apps on infant feeding, the quality of information in these resources should be assessed to identify whether consumers have access to credible and reliable information.

Objective: This systematic analysis provides perspectives on the information available about infant feeding on websites and smartphone apps.

Methods: A systematic analysis was conducted to assess the quality, comprehensibility, suitability, and readability of websites and apps on infant feeding using a developed tool. Google and Bing were used to search for websites from Australia, while the App Store for iOS and Google Play for Android were used to search for apps. Specified key words including baby feeding, breast feeding, formula feeding and introducing solids were used to assess websites and apps addressing feeding advice. Criteria for assessing the accuracy of the content were developed using the Australian Infant Feeding Guidelines.

Results: A total of 600 websites and 2884 apps were screened, and 44 websites and 46 apps met the selection criteria and were analyzed. Most of the websites (26/44) and apps (43/46) were noncommercial, some websites (10/44) and 1 app were commercial and there were 8 government websites; 2 apps had university endorsement. The majority of the websites and apps were rated poor quality. There were two websites that had 100% coverage of information compared to those rated as fair or poor that had low coverage. Two-thirds of the websites (65%) and almost half of the apps (47%) had a readability level above the 8th grade level.

Conclusions: The findings of this unique analysis highlight the potential for website and app developers to merge user requirements with evidence-based content to ensure that information on infant feeding is of high quality. There are currently no apps available to consumers that address a variety of infant feeding topics. To keep up with the rapid turnover of the evolving technology, health professionals need to consider developing an app that will provide consumers with a credible and reliable source of information about infant feeding, using quality assessment tools and evidence-based content.

Acute psychophysiological relationships between mood, inflammatory and cortisol changes in response to simulated physical firefighting work and sleep restriction

This study examined how changes in wildland firefighters' mood relate to cytokine and cortisol levels in response to simulated physical firefighting work and sleep restriction. Firefighters completed 3 days of simulated wildfire suppression work separated by an 8-h (control condition; n = 18) or 4-h sleep opportunity (sleep restriction condition; n = 17) each night. Firefighters' mood was assessed daily using the Mood Scale II and Samn-Perelli fatigue scale. Participants also provided samples for the determination of salivary cortisol and pro- (IL-6, IL-8, IL-1β, TNF-α) and anti-inflammatory (IL-4, IL-10) cytokine levels. An increase in the positive mood dimension Happiness was related to a rise in IL-8 and TNF-α in the sleep restriction condition. A rise in the positive mood dimension Activation among sleep restricted firefighters was also related to higher IL-6 levels. An increase in the negative mood dimension Fatigue in the sleep restriction condition was associated with increased IL-6, TNF-α, IL-10 and cortisol levels. In addition, an increase in Fear among sleep restricted firefighters was associated with a rise in TNF-α. Elevated positive mood and immune activation may reflect an appropriate response by the firefighters to these stressors. To further understand this relationship, subsequent firefighting-based research is needed that investigates whether immune changes are a function of affective arousal linked to the expression of positive moods. Positive associations between negative mood and inflammatory and cortisol levels to physical work and restricted sleep provide useful information to fire agencies about subjective fire-ground indicators of physiological changes.

Relationships between inflammatory cytokine and cortisol responses in firefighters exposed to simulated wildfire suppression work and sleep restriction

The interplay between inflammatory and cortisol responses modulates an appropriate response to a stressor. Exposure to severe stressors, however, may alter the actions and relationships of these responses and contribute to negative health outcomes. Physical work and sleep restriction are two stressors faced by wildland firefighters, yet their influence on the relationship between inflammatory and cortisol responses is unknown. The aim of the present study was to quantify the relationship between the cytokine and cortisol responses to sleep restriction while performing simulated physical wildfire suppression work. Firefighters completed 3 days of simulated physical firefighting work separated by either an 8-h (Control condition; n = 18) or 4-h sleep (Sleep restriction condition; n = 17) opportunity on each of the two nights. Salivary cortisol and inflammatory cytokines (IL-6, IL-8, IL-1β, TNF-α, IL-4, and IL-10) were measured throughout each day. An increase in morning IL-6 was related to a rise (6.2%, P = 0.043) in evening cortisol among firefighters in the sleep restriction condition. Higher morning IL-6 levels were related to increased (5.3%, P = 0.048) daily cortisol levels, but this relationship was not different between conditions. Less pronounced relationships were demonstrated between TNF-α, IL-10, IL-4, and cortisol independent of the sleep opportunity, but relationships did not persist after adjusting for demographic factors and other cytokines. These findings quantify the relationship between cytokine and cortisol responses among wildland firefighters exposed to simulated occupational stressors. Potential disturbances to the IL-6 and cortisol relationship among sleep-restricted firefighters' supports further investigations into the negative health effects related to possible imbalances between these systems.

Sex, fat and the tilt of the earth: effects of sex and season on the feeding response to centrally administered leptin in sheep

Whilst there have been many studies in various species examining the effects of leptin on food intake, there is a paucity of data comparing responsiveness in the two sexes. We have, therefore, addressed this issue in sheep. Because this species shows seasonal variation in voluntary food intake (VFI), we also considered the possibility that there might be seasonal variation in the responsivity to leptin. Centrally administered leptin was relatively ineffective as a satiety factor in either sex during AUTUMN: In Spring, leptin had a profound inhibitory effect on VFI in the females, but only a slight effect in males. These data indicate that responsiveness to leptin depends on sex and also on season in animals that are substantially affected by photoperiod.

The extended Infant Feeding, Activity and Nutrition Trial (InFANT Extend) Program : a cluster-randomized controlled trial of an early intervention to prevent childhood obesity

BACKGROUND: Understanding how we can prevent childhood obesity in scalable and sustainable ways is imperative. Early RCT interventions focused on the first two years of life have shown promise however, differences in Body Mass Index between intervention and control groups diminish once the interventions cease. Innovative and cost-effective strategies seeking to continue to support parents to engender appropriate energy balance behaviours in young children need to be explored. METHODS/DESIGN: The Infant Feeding Activity and Nutrition Trial (InFANT) Extend Program builds on the early outcomes of the Melbourne InFANT Program. This cluster randomized controlled trial will test the efficacy of an extended (33 versus 15 month) and enhanced (use of web-based materials, and Facebook® engagement), version of the original Melbourne InFANT Program intervention in a new cohort. Outcomes at 36 months of age will be compared against the control group. DISCUSSION: This trial will provide important information regarding capacity and opportunities to maximize early childhood intervention effectiveness over the first three years of life. This study continues to build the evidence base regarding the design of cost-effective, scalable interventions to promote protective energy balance behaviors in early childhood, and in turn, promote improved child weight and health across the life course. TRIAL REGISTRATION: ACTRN12611000386932 . Registered 13 April 2011.

Preference for feeding at habitat edges declines among juvenile blue crabs as oyster reef patchiness increases and predation risk grows

Both habitat patchiness and behaviorally-mediated indirect effects (BMIEs; predator- induced changes in prey behavior that affect the prey's resources) are important in many food webs, but the relationships between these 2 factors have yet to be investigated. To explore effects of habitat patchiness and variation in perceived risk of predation on food-web dynamics, we conducted a factorial experiment in a model aquatic food chain of predator-prey-resource using 2 contrasting predators (adult blue crab Callinectes sapidus and toad fish Opsanus tau), juvenile blue crab as prey, and mussel Geukensia demissa as resource. Both predator presence and habitat patchiness influenced the prey's preference for consuming resources at patch edges instead of interiors. The preference of prey for consuming resources at habitat edges was 4 times stronger in continuous oyster reef habitat than in smaller habitat patches. This suggests that interior resources in continuous habitat experience a refuge from consumption, but this refuge is largely lost in patchy habitat. The mere presence of predators reduced the prey's preference for consuming resources at habitat edges. This BMIE was significant for the ambush predator (toadfish) and the treatment containing both predators, but not for the actively hunting predator (adult blue crab). We conclude that habitat patchiness and predator presence can jointly affect resource distribution by inducing shifts in prey foraging behavior, revealing a need to incorporate BMIEs into habitat fragmentation studies. This conclusion has broad and growing relevance as anthropogenic factors increasingly modify predator abundances and fragment coastal habitats. © Inter-Research 2012.

Feeding ecology of King George whiting Sillaginodes punctatus (Perciformes) recruits in seagrass and unvegetated habitats. Does diet reflect habitat utilization?

This study investigated the feeding ecology of King George whiting Sillaginodes punctatus recruits to determine how diet composition varies between habitat types (seagrass and unvegetated habitats), and between sites separated by distance. Broad-scale sampling of seagrass and unvegetated habitats at nine sites in Port Phillip Bay (Australia) indicated the diet composition varied more by distance into the bay than by habitat. Near the entrance to the bay the diet was dominated by harpacticoids and gammarid amphipods, in the middle reaches of the bay the diet was completely dominated by harpacticoids, while at sites furthest into the bay, mysids and crab zoea were also important. Abundances of prey in guts was significantly higher between 1000 and 2200 hours compared with other times, indicating diurnal feeding. Laboratory determined gut evacuation rate (based on an exponential model) was estimated to be -0·54. Daily rations were highly variable among sites and habitat types. Sillaginodes punctatus recruits consumed much higher quantities of prey on unvegetated habitat than seagrass habitat at some middle reach sites; with prey consumption of harpacticoid copepods on unvegetated habitat approaching 3000 individuals per day at one site. The results of this study provide insight into why habitat associations of S. punctatus recruits within mosaics of seagrass and unvegetated habitat show high spatial variation.

Sleep restriction across a simulated firefighting deployment: the impact on acute stress responses

 This research demonstrated how exposure to physical work and restricted sleep can trigger an increase in firefighters’ immune and hormonal stress responses. The work also explored psychophysiological interactions between responses, with findings that suggest when sleep restricted, firefighters’ show a worsening in mood which relates to elevated hormonal and immune changes.

A qualitative study of the infant feeding beliefs and behaviours of mothers with low educational attainment

BACKGROUND: Infancy is an important period for the promotion of healthy eating, diet and weight. However little is known about how best to engage caregivers of infants in healthy eating programs. This is particularly true for caregivers, infants and children from socioeconomically disadvantaged backgrounds who experience greater rates of overweight and obesity yet are more challenging to reach in health programs. Behaviour change interventions targeting parent-infant feeding interactions are more likely to be effective if assumptions about what needs to change for the target behaviours to occur are identified. As such we explored the precursors of key obesity promoting infant feeding practices in mothers with low educational attainment.

METHODS: One-on-one semi-structured telephone interviews were developed around the Capability Opportunity Motivation Behaviour (COM-B) framework and applied to parental feeding practices associated with infant excess or healthy weight gain. The target behaviours and their competing alternatives were (a) initiating breastfeeding/formula feeding, (b) prolonging breastfeeding/replacing breast milk with formula, (c) best practice formula preparation/sub-optimal formula preparation, (d) delaying the introduction of solid foods until around six months of age/introducing solids earlier than four months of age, and (e) introducing healthy first foods/introducing unhealthy first foods, and (f) feeding to appetite/use of non-nutritive (i.e., feeding for reasons other than hunger) feeding. The participants' education level was used as the indicator of socioeconomic disadvantage. Two researchers independently undertook thematic analysis.

RESULTS: Participants were 29 mothers of infants aged 2-11 months. The COM-B elements of Social and Environmental Opportunity, Psychological Capability, and Reflective Motivation were the key elements identified as determinants of a mother's likelihood to adopt the healthy target behaviours although the relative importance of each of the COM-B factors varied with each of the target feeding behaviours.

CONCLUSIONS: Interventions targeting healthy infant feeding practices should be tailored to the unique factors that may influence mothers' various feeding practices, taking into account motivational and social influences.