Tart cherry juice (TC) and pomegranate juice (POM) have been demonstrated to reduce symptoms of exercise-induced muscle damage (EIMD), but their effectiveness has not been compared. This randomized, double-blind, parallel study compared the effects of TC and POM on markers of EIMD. Thirty-six non-resistance trained men (age 24.0 (Interquartile Range (IQR) 22.0, 33.0) years, body mass index (BMI) 25.6 ± 4.0 kg·m−2) were randomly allocated to consume 2 × 250 mL of: TC, POM, or an energy-matched fruit-flavored placebo drink twice daily for nine days. On day 5, participants undertook eccentric exercise of the elbow flexors of their non-dominant arm. Pre-exercise, immediately post-exercise, and at 24 h, 48 h, 72 h and 96 h post-exercise, maximal isometric voluntary contraction (MIVC), delayed onset muscle soreness (DOMS), creatine kinase (CK), and range of motion (ROM) were measured. The exercise protocol induced significant decreases in MIVC (p < 0.001; max decrease of 26.8%, 24 h post-exercise) and ROM (p = 0.001; max decrease of 6.8%, 72 h post-exercise) and significant increases in CK (p = 0.03; max increase 1385 U·L−1, 96 h post-exercise) and DOMS (p < 0.001; max increase of 26.9 mm, 48 h post-exercise). However, there were no statistically significant differences between treatment groups (main effect of group p > 0.05 or group x time interaction p > 0.05). These data suggest that in non-resistance trained men, neither TC nor POM enhance recovery from high-force eccentric exercise of the elbow flexors.

IntroductionGout is a painful form of inflammatory arthritis associated with several comorbidities, particularly cardiovascular disease. Cherries, which are rich in anti-inflammatory and antioxidative bioactive compounds, are proposed to be efficacious in preventing and treating gout, but recommendations to patients are conflicting. Cherry consumption has been demonstrated to lower serum urate levels and inflammation in several small studies. One observational case cross-over study reported that cherry consumption was associated with reduced risk of recurrent gout attacks. This preliminary evidence requires substantiation. The proposed randomised clinical trial aims to test the effect of consumption of tart cherry juice on risk of gout attacks.Methods and analysisThis 12-month, parallel, double-blind, randomised, placebo-controlled trial will recruit 120 individuals (aged 18–80 years) with a clinical diagnosis of gout who have self-reported a gout flare in the previous year. Participants will be randomly assigned to an intervention group, which will receive Montmorency tart cherry juice daily for a 12-month period, or a corresponding placebo group, which will receive a cherry-flavoured placebo drink. The primary study outcome is change in frequency of self-reported gout attacks. Secondary outcome measures include attack intensity, serum urate concentration, fractional excretion of uric acid, biomarkers of inflammation, blood lipids and other markers of cardiovascular risk. Other secondary outcome measures will be changes in physical activity and functional status. Statistical analysis will be conducted on an intention-to-treat basis.Ethics and disseminationThis study has been granted ethical approval by the National Research Ethics Service, Yorkshire and The Humber—Leeds West Research Ethics Committee (ref: 18/SW/0262). Results of the trial will be submitted for publication in a peer-reviewed journal.Trial registration numberNCT03621215.

Objective: To assess the alignment of YouTube® videos providing dietary recommendations for gout with evidence-based guidelines targeted at the United Kingdom (UK) population and to establish their quality. Design: A content analysis of YouTube® videos providing dietary recommendations for gout was undertaken. Videos were categorised by video source. Each video’s dietary recommendations for gout were compared with three evidence-based guidelines for gout, producing a compliance score. Presence of non-guideline advice was assessed. Understandability and actionability were evaluated using the Patient Education Material Assessment Tool for Audio-Visual Materials. Reliability was assessed using an adapted-DISCERN tool and educational quality using the Global Quality Score Five-Point Scale. Differences between video source and continuous variables were assessed using one-way Kruskal-Wallis H tests. For categorical variables, associations were investigated using Fisher-Freeman-Halton tests. Setting: Online, May-June 2020. Participants: 131 videos. Results: Alignment of videos with evidence-based guidelines was poor (median compliance score 27% (IQR 17-37%)). Additionally, 57% of videos contained non-guideline advice. The health professional source group had the fewest videos containing non-guideline advice, but this was only significantly lower than the naturopath group (31% vs 81%, p = 0.009). Almost 70% of videos were considered poorly actionable and 50% poorly understandable. Most videos were rated poor for reliability (79%) and poor to generally poor for educational quality (49%). Conclusions: YouTube® videos providing dietary recommendations for gout frequently fail to conform to evidence-based guidelines and their educational quality, reliability, understandability, and actionability is often poor. More high-quality, comprehensive, evidence-based YouTube® videos are required for UK gout patients.

Gout is a painful form of inflammatory arthritis that affects approximately 3% of adults in the United Kingdom (UK). It is associated with several comorbidities including cardiovascular disease (CVD). Diet can contribute to the prevention and management of gout and several evidence-based dietary guidelines for gout have consequently been published. Nevertheless, gout patients may use alternative sources for dietary recommendations, for example YouTube® videos. One dietary recommendation that has received considerable attention in the prevention and management of gout is the consumption of cherries, but evidence supporting this is limited to observational research and studies without appropriate controls. Therefore, over three studies, this thesis aimed to explore the role of dietary modification in the prevention and management of gout and CVD, with a particular focus on tart cherries. In Study 1, the accuracy, reliability, quality, and understandability of dietary information for gout provided on the YouTube® platform was assessed. This study highlighted that dietary recommendations for gout on YouTube® often fail to align with evidence-based guidelines in the UK, are inconsistent, and are not always suitable for patients. Almost 30% of videos analysed included advice to consume cherries. Study 2 compared the acute effects of tart cherry juice with a neutral water control on uric acid levels, inflammation, and CVD risk markers in healthy individuals. A single serving of juice was not found to exert any acute health benefits. However, diurnal fluctuations in markers were detected. The effects of 12 months of daily tart cherry supplementation on gout flares, uric acid levels, inflammation, and CVD risk in gout patients were evaluated in Study 3. Compared with a placebo drink, long-term tart cherry supplementation did not present any health-promoting benefits for gout or CVD. This study was limited by low sample size. Nevertheless, long-term cherry juice supplementation was shown to be feasible and accepted by individuals with gout. Overall, this thesis is unable to support a direct role of tart cherry juice in the prevention and management of gout and CVD, despite the prevalence of this recommendation. However, it appears to be an appropriate alternative to drinks that are known to exacerbate risk marker of gout and CVD. Placebo-controlled studies with larger sample sizes are required to confirm these findings.

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