Adolescent athletes have better general than sports nutrition knowledge and lack awareness of supplement recommendations: a systematic literature review

Nutrition knowledge (NK) impacts food choices and may be improved through educational programmes. Identifying knowledge gaps related to NK among adolescent athletes may guide future nutrition education programmes. This review aimed to systematically review the level of NK in adolescent athletes based on the currently available published literature. The protocol for this review was registered with PROSPERO (CRD42022321765). A literature search was conducted in April 2022 using MEDLINE, CINAHL, SPORTDiscus, Web of Science and SCOPUS databases. The study design was not restricted, provided that a quantitative NK score was reported for adolescent athletes. Studies were limited to the English language and published between 2010 and April 2022. Studies were assessed for quality and risk of bias using the Academy of Nutrition and Dietetics Quality Appraisal Checklist. Data extracted included demographics, questionnaire name, number of items, validation status and mean total and subsection NK scores. Meta-analyses were inappropriate due to the heterogeneity of NK assessment tools; therefore, results were presented narratively. Thirty-two studies that assessed NK of 4553 adolescent athletes and 574 comparison participants were included. Critical appraisal of studies resulted in neutral rating 'moderate quality' for most (n 30) studies. Studies lacked justification for sample size and often used inadequately validated questionnaires. NK scores ranged from poor (33·3 %) to excellent (90·6 %). The level of NK across studies is difficult to determine due to heterogenous questionnaires often lacking appropriate validation. NK should be assessed using tools validated in the relevant population or revalidated tools previously used for other populations.

Practical application of the Crohn's disease exclusion diet as therapy in an adult Australian population

There is demand from patients and clinicians to use the Crohn's disease exclusion diet (CDED) with or without partial enteral nutrition (PEN). However, the therapeutic efficacy and nutritional adequacy of this therapy are rudimentary in an adult population. This review examines the evidence for the CDED in adults with active luminal Crohn's disease and aims to provide practical guidance on the use of the CDED in Australian adults. A working group of nine inflammatory bowel disease (IBD) dietitians of DECCAN (Dietitians Crohn's and Colitis Australian Network) and an IBD gastroenterologist was established. A literature review was undertaken to examine (1) clinical indications, (2) monitoring, (3) dietary adequacy, (4) guidance for remission phase, and (5) diet reintroduction after therapy. Each diet phase was compared with Australian reference ranges for food groups and micronutrients. CDED with PEN is nutritionally adequate for adults containing sufficient energy and protein and meeting > 80% of the recommended daily intake of key micronutrients. An optimal care pathway for the clinical use of the CDED in an adult population was developed with accompanying consensus statements, clinician toolkit, and patient education brochure. Recommendations for weaning from the CDED to the Australian dietary guidelines were developed. The CDED + PEN provides an alternate partial food-based therapy for remission induction of active luminal Crohn's disease in an adult population. The CDED + PEN should be prioritized over CDED alone and prescribed by a specialist IBD dietitian. DECCAN cautions against using the maintenance diet beyond 12 weeks until further evidence becomes available.

Processed Food as a Risk Factor for the Development and Perpetuation of Crohn's Disease-The ENIGMA Study

(1) Background: Developing countries have experienced a rapid recent rise in Inflammatory Bowel Disease (IBD) incidence and emerging evidence suggests processed foods and food additives may predispose one to the development and perpetuation of Crohn’s disease (CD). The aim of this study was to evaluate processed food and food additive intake in CD patients and controls, in Australia (high CD incidence), Hong Kong (intermediate incidence) and mainland China (emerging incidence). (2) Methods: In 274 CD patients (CD), 82 first-degree relatives (FDR), 83 household members (HM) and 92 healthy unrelated controls (HC) from Australia (n = 180), Hong Kong (HK) (n = 160) and mainland China (n = 191) we estimated early life (0–18 years), recent (12 months), and current processed and food additive intake, using validated questionnaires and a 3-day-food diary. (3) Results: Early life processed food intake: Combining all regions, CD were more likely to have consumed soft drinks and fast foods than HM, more likely to have consumed processed fruit and snacks than their FDR, and more likely to have consumed a range of processed foods than HC. HK and China CD patients were more likely to have consumed a range of processed foods than HC. Recent food-additive intake (12-months): Combining all regions, CD patients had significantly higher intakes of aspartame and sucralose, and polysorbate-80, than HC, and more total emulsifiers, artificial sweeteners, and titanium dioxide than FDR and HC. HK and China CD patients had a higher intake of almost all food additives than all controls. Current additive intake (3-days): Australian and HK CD patients had higher total food-additive intake than FDR, and HK CD patients had a higher intake of total food-additives and emulsifiers than HM. (4) Conclusions: CD patients have been exposed to more processed food and food additives than control groups, which may predispose them to CD development and ongoing inflammation.

Childhood antibiotics as a risk factor for Crohn's disease: The ENIGMA International Cohort Study

Background and Aim

Environmental factors play a key role in development of Crohn's disease (CD), thought to be mediated by changes in the gut microbiota. We aimed to delineate the potential contribution of antibiotic exposure to subsequent development of CD, across diverse geographical populations.

Methods

This case–control study in Australia and three cities in China (Hong Kong, Guangzhou, and Kunming) included four groups: patients with CD, at‐risk individuals including non‐affected first‐degree relatives (FDRs) and household members of CD patients (HM), and unrelated healthy controls (HCs). Environmental risk factors, including childhood antibiotic use and 13 other categories, were assessed using a self‐developed questionnaire. Logistic regression and conditional logistic regression were used to determine environmental factors associated with CD development.

Results

From 2017 to 2019, a total of 254 patients with CD (mean age: 37.98 ± 13.76 years; 58.3% male), 73 FDR (mean age: 49.35 ± 13.28 years; 46.6% male), 122 HMs (including FDR) (mean age: 45.50 ± 13.25 years; 47.5% male), and 78 HC (mean age: 45.57 ± 11.24; 47.4% male) were included. Comparing CD patients with their FDR and HMs, antibiotic use before 18 years old was a risk factor for CD development (adjusted odds ratio [OR] 3.46, 95% confidence interval [CI] 1.38–8.69; P = 0.008). There were no significant differences in other childhood environmental risk factors between CD and their FDR or HMs. Subgroup analysis showed that antibiotic use <18 years old was a risk factor for CD development in the Chinese (adjusted OR 4.80, 95% CI 1.62–12.24; P = 0.005) but not in Australian populations (OR 1.80, 95% CI 0.33–9.95; P = 0.498).

Conclusion

Use of antibiotics <18 years was a risk factor for CD development. Attention should be paid to identifying modifiable environmental risk factors in early childhood, especially in at‐risk families.

Diet and gut microbiome in gastrointestinal disease

The composition and function of the dynamic microbial community that constitutes the gut microbiome is continuously shaped by the host genome, mode of birth delivery, geography, life stage, antibiotic consumption, and diet. Diet is one of the most potent factors in determining microbiome integrity. Dietary factors in early life appear to substantially determine the risk of later health or disease; for example, exposure to ultra-processed foods in childhood or adolescence may increase the risk of the later development of inflammatory bowel disease or colorectal cancer, thought to be mediated by modulation of the gut microbiota. Dietary factors when gut diseases are established influence symptoms and disease activity, can form a risk factor for ongoing disease, or can be used as therapy to decrease disease activity. The characterization of dietary content is currently complex and imperfect, but tools are emerging to define precisely the nature of dietary composition. Similarly, the revolution in microbial analysis allows greater understanding of how diet influences microbial composition and function. Defining the interaction between diet, the gut microbiome, and gastrointestinal disease is leading to radical changes in our clinical approach to these disorders.

The Dietary Inflammatory Index and Human Health: An Umbrella Review of Meta-Analyses of Observational Studies

Numerous observational studies have investigated the role of the Dietary Inflammatory Index (DII®) in chronic disease risk. The aims of this umbrella review and integrated meta-analyses were to systematically synthesize the observational evidence reporting on the associations between the DII and health outcomes based on meta-analyses, and to assess the quality and strength of the evidence for each associated outcome. This umbrella review with integrated meta-analyses investigated the association between the DII and a range of health outcomes based on meta-analyses of observational data. A credibility assessment was conducted for each outcome using the following criteria: statistical heterogeneity, 95% prediction intervals, evidence for small-study effect and/or excess significance bias, as well as effect sizes and P values using calculated random effects meta-analyses. In total, 15 meta-analyses reporting on 38 chronic disease-related outcomes were included, incorporating a total population of 4,360,111 subjects. Outcomes (n = 38) were examined through various study designs including case-control (n = 8), cross-sectional (n = 5), prospective (n = 5), and combination (n = 20) study designs. Adherence to a pro-inflammatory dietary pattern had a significant positive association with 27 (71%) of the included health outcomes (P value < 0.05). Using the credibility assessment, Class I (Convincing) evidence was identified for myocardial infarction only, Class II (Highly suggestive) evidence was identified for increased risk of all-cause mortality, overall risk of incident cancer, and risk of incident site-specific cancers (colorectal, pancreatic, respiratory, and oral cancers) with increasing (more pro-inflammatory) DII score. Most outcomes (n = 31) presented Class III (Suggestive) or lower evidence (Weak or No association). Pro-inflammatory dietary patterns were nominally associated with an increased risk of many chronic disease outcomes. However, the strength of evidence for most outcomes was limited. Further prospective studies are required to improve the precision of the effect size.

Dietary Guidance From the International Organization for the Study of Inflammatory Bowel Diseases

Recent evidence points to a plausible role of diet and the microbiome in the pathogenesis of both Crohn's disease (CD) and Ulcerative Colitis (UC). Dietary therapies based on exclusion of table foods and replacement with nutritional formulas and/or a combination of nutritional formulas and specific table foods may induce remission in CD. In UC, specific dietary components have also been associated with flare of disease. While evidence of varying quality has identified potential harmful or beneficial dietary components, physicians and patients at the present time do not have guidance as to which foods are safe, may be protective or deleterious for these diseases. The current document has been compiled by the nutrition cluster of the International Organization for the Study of Inflammatory Bowel Diseases (IOIBD) based on the best current evidence to provide expert opinion regarding specific dietary components, food groups and food additives that may be prudent to increase or decrease in the diet of patients with inflammatory bowel diseases to control and prevent relapse of inflammatory bowel diseases.

Australian team sports athletes prefer dietitians, the internet and nutritionists for sports nutrition information

AIM

To evaluate the information sources that are used and preferred by Australian athletes and to assess if preferences influence nutrition knowledge (NK).

METHODS

Elite and non-elite Australian team sport athletes, playing Australian football (AF), cricket, lawn bowls, soccer or hockey, were recruited via the sporting organisations' qualified sports dietitians or club presidents. Athletes completed one of two online, validated sports NK questionnaires. Frequency analysis on previous sources of advice, preferred sources of information and preferred type of support were assessed. Differences in NK scores (%) based on previous sources of dietary advice and preferences for obtaining information were assessed using t test or Mann-Whitney U test.

RESULTS

Demographic and information source questions were completed by 410 athletes; 331 also completed NK questions. Athletes were mostly non-elite (76%) and AF players (79%). Forty-four per cent of athletes reported having previously received advice from a dietitian. Twenty per cent, 19% and 16% of athletes chose "dietitian," "internet" and "nutritionist" as their preferred source of nutrition information, respectively. Athletes preferred information on sports nutrition (35%), individual consultations (33%), and information on general healthy eating (33%), over cooking classes (4%) and group presentations (3%). There were no significant associations between preferred and previous information sources and NK scores.

CONCLUSIONS

Australian athletes prefer dietitians, the internet and nutritionists for sports nutrition information. There is an interest in and need for access to a qualified sports dietitian and reputable internet-based nutrition information. Education programs and advice given to athletes need to be evaluated.

A Systematic Review of Athletes' and Coaches' Nutrition Knowledge and Reflections on the Quality of Current Nutrition Knowledge Measures

Context: Nutrition knowledge can influence dietary choices and impact on athletic performance. Valid and reliable measures are needed to assess the nutrition knowledge of athletes and coaches. Objectives: (1) To systematically review the published literature on nutrition knowledge of adult athletes and coaches and (2) to assess the quality of measures used to assess nutrition knowledge. Data Sources: MEDLINE, CINAHL, SPORTDiscuss, Web of Science, and SCOPUS. Study Selection: 36 studies that provided a quantitative measure of nutrition knowledge and described the measurement tool that was used were included. Data extraction: Participant description, questionnaire description, results (mean correct and responses to individual items), study quality, and questionnaire quality. Data synthesis: All studies were of neutral quality. Tools used to measure knowledge did not consider health literacy, were outdated with regards to consensus recommendations, and lacked appropriate and adequate validation. The current status of nutrition knowledge in athletes and coaches is difficult to ascertain. Gaps in knowledge also remain unclear, but it is likely that energy density, the need for supplementation, and the role of protein are frequently misunderstood. Conclusions: Previous reports of nutrition knowledge need to be interpreted with caution. A new, universal, up-to-date, validated measure of general and sports nutrition knowledge is required to allow for assessment of nutrition knowledge.