Introduction Improving healthy lifestyles of adolescents is challenging. Citizen Science is a way to engage them in the design and delivery of interventions, and may also increase their interest in science, technology, engineering and mathematics (STEM). The Science Engagement to Empower aDolescentS (SEEDS) project aims to use an equity-lens, and engage and empower boys and girls from deprived areas by designing and cocreating interventions to promote healthy lifestyles, and to seed interest in STEM. Methods and analysis SEEDS is a cluster randomised controlled trial in four countries (Greece, the Netherlands, Spain and the UK). Each country will recruit six to eight high schools from lower socioeconomic neighbourhoods. Adolescents aged 13–15 years are the target population. High schools will be randomised into intervention or control group. Each country will select 15 adolescents from intervention schools called ambassadors, who will be involved throughout the project. In each country, focus groups with ambassadors and stakeholders will focus on physical activity, snacking behaviour and STEM. The input from focus groups will be used to shape Makeathon events, cocreation events where adolescents and stakeholders will develop the interventions. The resultant intervention will be implemented in the intervention schools during 6 months. In total, we aim to recruit 720 adolescents who will complete questionnaires related to healthy lifestyles and STEM outcomes at baseline (November 2021) and after the 6 months (June 2022). Ethics and dissemination The four countries obtained approval from their corresponding Ethics Committees (Greece: Bioethics Committee of Harokopio University; the Netherlands: The Medical Research Ethics Committee of the Erasmus Medical Center; Spain: The Drug Research Ethics Committee of the Pere Virgili Health Research Institute; UK: Sport and Health Sciences Ethics Committee of the University of Exeter). Informed consent will be collected from adolescents and their parents in line with General Data Protection Regulation legislation. The findings will be disseminated by conference presentations, publications in scientific peer-reviewed journals and during (local) stakeholders and public events. Lessons learnt and the main results will also be used to provide policy recommendations. Trial registration number NCT05002049.

Context: Adolescence is an optimal period to promote healthy lifestyles because behavior patterns are established in this stage. It has been suggested that engaging youth increases the effectiveness of interventions, but an overview is lacking. Objective: This study aims to evaluate the effectiveness of participatory research (PR) interventions, where adolescents (11–18 years old) from high-income countries had a significant role in the intervention development and/or delivery, compared with no (PR) intervention control groups on obesity-related outcomes and healthy lifestyle behaviors (HLBs). Data Sources: Eight databases (Embase, Medline ALL, Web of Science Core Collection, PsycINFO, ERIC, CINAHL, Scopus, and Cochrane Central Register of Controlled Trials) and Google Scholar were searched from 1990 to 2024 for randomized controlled trials (RCTs) and non-RCTs (in English). Data Extraction: Two researchers independently performed the data extraction and risk-of-bias assessment. Data Analysis: Sixteen studies were included and outcomes have been narratively described. Seven studies evaluated youth-led interventions, 3 studies evaluated co-created interventions, and 6 studies evaluated the combination of both. Six studies focused on physical activity (PA), 2 on nutrition, and 8 on a combination of PA, nutrition, and/or obesity-related outcomes. Ten studies presented at least 1 significant effect on PA, nutrition, or obesity-related outcomes in favor of the intervention group. Additionally, 12 studies were pooled in a meta-analysis. Whereas a small desired effect was found for fruit consumption, a small undesired effect was found for vegetable consumption. The pooled analysis found no significant effects on moderate–vigorous PA, total PA, and PA self-efficacy. Conclusion: We found some evidence that youth empowerment in research may have positive effects on obesity-related HLBs, specifically an increased fruit consumption. However, the overall evidence was inconclusive due to limited studies and the heterogeneity of the studies included. This overview may guide future public health interventions that aim to engage and empower adolescents. Systematic Review Registration: PROSPERO registration Nº CRD42021254135.

Background: Low muscle mass quantity/quality is needed to confirm sarcopenia diagnosis; however, no validated cut-off points exist. This study aimed to determine the diagnostic accuracy of sarcopenia through muscle mass quantity/quality parameters, using the bioimpedance analysis (BIA), isokinetic, and ultrasound tools in probable sarcopenic community-dwelling older adults (≥60 years). Also, it aimed to suggest possible new cut-off points to confirm sarcopenia diagnosis. Methods: A cross-sectional exploratory analysis study was performed with probable sarcopenic and non-sarcopenic older adults. BIA, isokinetic, and ultrasound parameters were evaluated. The protocol was registered on ClinicalTrials.gov (NCT05485402). Results: A total of 50 individuals were included, 38 with probable sarcopenia (69.63 ± 4.14 years; 7 men and 31 women) and 12 non-sarcopenic (67.58 ± 4.54 years; 7 men and 5 women). The phase angle (cut-off: 5.10° men, p = 0.003; 4.95° women, p < 0.001), peak torque (cut-off: 66.75 Newtons-meters (N-m) men, p < 0.001; 48.35 N-m women, p < 0.001), total work (cut-off: 64.00 Joules (J) men, p = 0.007; 54.70 J women, p = 0.001), and mean power (cut-off: 87.8 Watts (W) men, p = 0.003; 48.95 W women, p = 0.008) in leg extension, as well as the the forearm muscle thickness (cut-off: 1.41 cm (cm) men, p = 0.017; 0.94 cm women, p = 0.041), had great diagnostic accuracy in both sexes. Conclusions: The phase angle, peak torque, total work, and mean power in leg extension, as well as forearm muscle thickness, had great diagnostic accuracy in regard to sarcopenia, and the suggested cut-off points could lead to the confirmation of sarcopenia diagnosis, but more studies are needed to confirm this.

Background: Management of sarcopenia by nutritional and lifestyle interventions is a challenge. The aim is to assess the effectiveness of a phenolic‐rich extra virgin olive oil (EVOO), alone or combined with a prebiotic (PREB) (fructooligosaccharides and inulin), to improve skeletal muscle mass and function in home‐dwelling older adults (60–80 years) with at least one sarcopenia parameter altered. Methods: A 12‐week randomised, double‐blind, parallel, placebo‐controlled, three‐arm clinical trial was conducted. Intervention groups were as follows: (1) refined olive oil (ROO; 30 mL/day; 90‐mg caffeic acid) + maltodextrin placebo (7.5 g/day); (2) EVOO (30 mL/day; 296–300‐mg caffeic acid) + maltodextrin placebo (7.5 g/day); or (3) EVOO + prebiotic (EVOO + PREB; 30 mL/day + 7.5 g/day). Everyone followed co‐created dietary and physical activity recommendations. A 12‐week follow‐up after intervention cessation was assessed. Results: Thirty‐eight participants (69.6 ± 4.1 years; 31 women) with probable sarcopenia were assigned to ROO ( n = 13), EVOO ( n = 14) or EVOO + PREB ( n = 11) intervention groups. At the end‐of‐intervention, assessed by ultrasound, EVOO + PREB compared to EVOO significantly increased muscle thickness of the quadriceps in females, mean (95% CI) (0.230 cm [0.008; 0.45], p = 0.044), cross‐sectional area of the rectus femoris in all populations (0.827 cm ² [0.16; 1.5], p = 0.017) and females (0.569 cm ² [−1.0; −0.08], p = 0.024), and rectus femoris muscle thickness in all population (0.195 cm [0.04; 0.35] p = 0.015) and females (0.179 cm [0.05; 0.31] p = 0.009). Also, EVOO + PREB compared to ROO increased the cross‐sectional area of the rectus femoris (0.579 cm ² [0.07; 1.1], p = 0.026) and rectus femoris muscle thickness (0.133 cm [0.00; 0.27], p = 0.050) in females. At 12‐week follow‐up, EVOO and EVOO + PREB, compared to ROO, significantly increased skeletal muscle mass and appendicular skeletal muscle mass in all populations assessed by bioelectrical impedance analysis (BIA). Also, EVOO, compared to ROO, significantly increased skeletal muscle mass index and appendicular skeletal muscle mass index. In addition, at 12‐week follow‐up, EVOO, compared to ROO, improved the overall quality of life score in females. Conclusions: Consuming phenolic‐rich EVOO, alone or combined with prebiotics, improved muscle mass assessed by ultrasound at the end‐of‐intervention and by BIA at 12‐week follow‐up. Further studies are needed to confirm these promising results. Trial Registration: Registration number: NCT05485402; https://clinicaltrials.gov/study/NCT05485402 ; registration date: 03/08/2022.

Background: New approaches for the management of obesity, a worldwide problem and a major determinant of disability and mortality, are needed. Mastication influences appetite and satiety mechanisms via actual food or sham feeding. However, the effect of mastication of chewing gum, a type of sham feeding, on appetite regulation has not yet been elucidated. Objectives: Our aim was to evaluate the influence of chewing gum on appetite regulation, satiety, energy intake, and weight loss via randomized controlled Trials. Methods: This study was conducted in accordance with the 2020 PRISMA guidelines, and the protocol was registered in PROSPERO (CRD42023432699). Electronic databases MEDLINE^®/PubMed, Scopus, and Cochrane Central Register of Controlled Trials were searched from July 2023 to September 2024. The quality of each included study was assessed using the Cochrane risk of bias tool, RoB 2. Results: A total of eight articles with nine RCTs were included in this systematic review. Seven out of nine RCTs evaluated appetite regulation. Five out of seven RCTs reported a significant suppressing effect of hunger, three out of five RCTs reported a significant reduction in desire to eat, and three out of four reported a significant reduction in the desire to eat a sweet snack, all of them compared to the control group. However, the effects on satiety, energy intake, and weight loss are not conclusive. Conclusions: Chewing gum could be a promising non-pharmacological tool for obesity management through appetite regulation; however, further research, with sustained RCTs evaluating the sustained effects of gum chewing on appetite and weight management, is needed.

Management of sarcopenia by nutritional and lifestyle interventions is a challenge. The aim is to assess the effectiveness of a phenolic-rich extra virgin olive oil (EVOO), alone or combined with a prebiotic (PREB) (fructooligosaccharides and inulin), to improve skeletal muscle mass and function in home-dwelling older adults (60-80 years) with at least one sarcopenia parameter altered. A 12-week randomised, double-blind, parallel, placebo-controlled, three-arm clinical trial was conducted. Intervention groups were as follows: (1) refined olive oil (ROO; 30 mL/day; 90-mg caffeic acid) + maltodextrin placebo (7.5 g/day); (2) EVOO (30 mL/day; 296-300-mg caffeic acid) + maltodextrin placebo (7.5 g/day); or (3) EVOO + prebiotic (EVOO + PREB; 30 mL/day + 7.5 g/day). Everyone followed co-created dietary and physical activity recommendations. A 12-week follow-up after intervention cessation was assessed. Thirty-eight participants (69.6 ± 4.1 years; 31 women) with probable sarcopenia were assigned to ROO (n = 13), EVOO (n = 14) or EVOO + PREB (n = 11) intervention groups. At the end-of-intervention, assessed by ultrasound, EVOO + PREB compared to EVOO significantly increased muscle thickness of the quadriceps in females, mean (95% CI) (0.230 cm [0.008; 0.45], p = 0.044), cross-sectional area of the rectus femoris in all populations (0.827 cm² [0.16; 1.5], p = 0.017) and females (0.569 cm² [-1.0; -0.08], p = 0.024), and rectus femoris muscle thickness in all population (0.195 cm [0.04; 0.35] p = 0.015) and females (0.179 cm [0.05; 0.31] p = 0.009). Also, EVOO + PREB compared to ROO increased the cross-sectional area of the rectus femoris (0.579 cm² [0.07; 1.1], p = 0.026) and rectus femoris muscle thickness (0.133 cm [0.00; 0.27], p = 0.050) in females. At 12-week follow-up, EVOO and EVOO + PREB, compared to ROO, significantly increased skeletal muscle mass and appendicular skeletal muscle mass in all populations assessed by bioelectrical impedance analysis (BIA). Also, EVOO, compared to ROO, significantly increased skeletal muscle mass index and appendicular skeletal muscle mass index. In addition, at 12-week follow-up, EVOO, compared to ROO, improved the overall quality of life score in females. Consuming phenolic-rich EVOO, alone or combined with prebiotics, improved muscle mass assessed by ultrasound at the end-of-intervention and by BIA at 12-week follow-up. Further studies are needed to confirm these promising results. Registration number: NCT05485402; https://clinicaltrials.gov/study/NCT05485402; registration date: 03/08/2022.