Ultra-processed food (UPF) intake has been associated with negative health outcomes. Research investigating UPF intake and cognitive health outcomes has begun. The aim of this review is to summarise the existing evidence of associations between exposure to UPFs, as defined by the NOVA food classification system, and cognitive health outcomes. We conducted a systematic search across multiple databases for relevant studies up to October 2024. The Newcastle-Ottawa Scale was used to assess the quality of included studies. A narrative approach was used to summarise and integrate results across studies. 383 articles were screened and five met the inclusion criteria. The association between UPF intake and four different cognitive outcomes (dementia risk, cognitive impairment risk, cognitive performance and cognitive change trajectories) was explored. Three out of the five studies found a significant negative main effect of consuming UPF on the outcome of interest. All studies identified adverse associations of consumption; for some studies, these negative associations were isolated to a subgroup of the population or a subgroup of UPF type. Conclusions should be drawn with caution due to the limited number of studies available examining UPF intake according to NOVA and its association with cognitive outcomes, as well as the variability in cognitive measures assessed. Due to the novelty of this research area, more studies are required to help elucidate whether, and how, UPF may affect cognitive health. Additionally, future analyses should incorporate a measure of overall diet quality to aid in determining whether the effect of UPF is independent of dietary pattern or influenced by it. PROSPERO registration number CRD42024600338.

Background Nutrition is a modifiable driver of morbidity and mortality in the UK, yet nutrition education remains marginal within medical curricula. Despite guidance from the General Medical Council (GMC) and the Association for Nutrition (AfN), evidence suggests persistent under-provision. Methods We triangulated findings from: (1) a curriculum review and mapping exercise of UK medical schools; (2) a curriculum survey (n=31) of final-year or newly qualified students; and (3) a rapid review (2010–2025) of literature on nutrition education in UK medical programmes. Survey items mapped to AfN competencies and GMC Outcomes for Graduates. Results Across all data sources, nutrition education was inconsistently delivered, theoretical and rarely assessed. Most students (71%) reported receiving ≤10 hours of teaching. Although 84% rated nutrition as important, only 61% felt prepared to address nutrition issues. Confidence was lowest for practical skills (nutrition assessment, referral pathways and brief interventions). The rapid review identified longstanding barriers: low curricular legitimacy, limited assessment, insufficient faculty expertise and weak clinical integration. Enablers included nutrition leads, interprofessional learning and competency-aligned teaching. Conclusions Despite national prevention ambitions, nutrition remains insufficiently integrated into UK medical education. Aligning curricula with AfN/GMC standards, strengthening assessment, embedding leadership and co-designing applied teaching with students represent practical high-impact opportunities to develop prevention.

Background Malnutrition is common in patients with cancer. Limited data exist on the association between nutritional status, chemotherapy cycles and therapeutic responses in low-resource settings. This study investigated the association between pretreatment nutritional status, chemotherapy cycles and treatment response in Addis Ababa, Ethiopia, providing insights through count data analysis. Methods A multicentre prospective cohort study was conducted from February 2024 to June 2025, involving 400 patients with solid tumours followed from prior to chemotherapy to 1 month after completing treatment. Nutritional status was assessed using the Patient-Generated Subjective Global Assessment, and treatment response was measured using the Response Evaluation Criteria in Solid Tumours (V.1.1). Multivariable logistic and Poisson regression analyses were used to determine the association between malnutrition, treatment response and number of chemotherapy cycles. Results At baseline, 39% of the patients exhibited severe malnutrition. Of the 400 recruited participants, only 204 (51%) completed six or more chemotherapy cycles, and 19.6% showed progressive disease (PD). In bivariate analysis, severe malnutrition was associated with PD (crude OR = 2.67 (95% CI: 1.12 to 6.1)). In the multivariable logistic regression analysis, low dietary diversity (adjusted OR (AOR) = 3.63 (95% CI: 1.19 to 11.05)) and low performance status (AOR = 4.3 (95% CI 1.35 to 13.67)) were associated with PD. Additionally, based on Poisson regression, patients with severe malnutrition received 17% fewer chemotherapy cycles than well-nourished patients (incidence rate ratio = 0.83 (95% CI: 0.73 to 0.93)). Conclusions Based on a prospective cohort study, malnutrition may not predict chemotherapy response. However, it was associated with a reduced number of chemotherapy cycles. Therefore, early nutritional assessment and intervention are imperative to reduce treatment dropouts. Patients should also be encouraged to consume a diverse diet rich in essential nutrients to improve their treatment responses.

Objectives This study aimed to investigate the association between vitamin E intake, its serum levels and all-cause mortality by smoking status. Participants This study included 30280 adults from National Health and Nutrition Examination Survey (NHANES) 1999–2014. We categorised participants into current smokers, former smokers and non-smokers. Measurements Vitamin E intake was assessed via a 24-hour dietary recall and categorised into tertiles. Serum vitamin E levels (alpha-tocopherol) were measured using high-performance liquid chromatography. Mortality data were obtained through linkage to the National Death Index. Results During a median follow-up of 119.7 months, 15.4% of participants experienced all-cause mortality. The former smokers were the oldest and had the highest proportions of men, hypertension, diabetes mellitus and chronic kidney disease. This group had the highest Body Mass Index, serum cholesterol, uric acid and urinary albumin creatinine ratio. The proportion of participants who met the recommended dietary allowance (RDA) of vitamin E was only 2491 (8.3%), and the RDA meeting rate was highest in the order of non-smokers, former smokers and current smokers. Cox regression analysis revealed that higher vitamin E intake was associated with lower mortality risks in former smokers and non-smokers, but not in current smokers. The association between vitamin E intake and mortality in former smokers was observed, particularly those who had quit smoking for more than 20 years. Serum vitamin E levels were associated with mortality only in non-smokers. Conclusions Vitamin E intake was not associated with a lower mortality risk in current smokers but was associated with lower mortality risk in former smokers and non-smokers. This finding suggests the importance of smoking cessation and the potential benefits of antioxidant vitamin E in former smokers.

Objective Primary headaches are a prevalent health concern among children and adolescents, often affecting their quality of life. Emerging evidence suggests that hydration status may play a role in primary headache occurrence and severity. This study aimed to evaluate the impact of hydration on headache characteristics in children and adolescents with primary headaches. Methods A total of 60 children and adolescents diagnosed with primary headaches were enrolled from the outpatient Headache Clinic of the Department of Paediatric Neurology at the University Children’s Hospital, University Medical Centre Ljubljana, Slovenia, between May and September 2023. Participants received personalised hydration recommendations based on established Slovenian dietary guidelines and guidance on appropriate fluid choices. The primary outcome was headache frequency, intensity, and duration, measured at baseline and after the four-month intervention using a headache questionnaire. Fluid intake was assessed using a Food Frequency Questionnaire, while hydration status was evaluated in a sub-group (n=28) using bioelectrical impedance analysis. Results Following the four-month intervention, participants demonstrated a significant increase in daily fluid intake from 5–8 glasses/day (one glass=200 mL) to 8–10 glasses/day (p<0.001), which was associated with a reduction in primary headache frequency (1–2 times/week to 3 times/month; p<0.001) and headache intensity (7/10–5/10; p<0.001). However, no significant effect was observed on headache duration (3 hours/headache to 2 hours/headache; p=0.19). Following the intervention, hydration status improved, as evidenced by significant increases in median total body water and extracellular water (p<0.001 and p=0.007, respectively), while the total body water to extracellular water ratio remained unchanged. Conclusions This study provides novel evidence supporting adequate fluid intake and hydration as a non-pharmacological intervention for reducing primary headache frequency and intensity in paediatric populations.

Background Low-carbohydrate diets (LCD) improve glycaemic control (HbA1c) and weight in individuals with type 2 diabetes (T2D). Few studies have explored both the quantitative effects and qualitative experiences of individuals following LCD. Methods Single-arm, prospective, observational study of a carbohydrate-reduced diet (CRD) on HbA1c, weight and the acceptability in people with T2D and HbA1c ≥6.5% (48 mmol/mol). Participants were recruited from general practitioner surgeries and enrolled in an eight-session CRD health coaching programme delivered by The Lifestyle Club, with follow-up over 6 months. Blood samples, anthropometric data and dietary adherence were measured at baseline and at 6 months. Participants were informed about the semi-structured interviews at consent and invited after visit 2. Results Forty-eight participants were included (mean age 67±10 years; 55% male). Carbohydrate intake decreased from 226.0 g/day at baseline to 126.3 g/day at 6 months (p<0.001) and the proportion of energy from carbohydrates decreased from 42.6% to 29.7% (p<0.001). HbA1c decreased from 60.0±12.9 mmol/mol to 49.7±9.0 mmol/mol at 6 months (p<0.001). Mean body weight decreased by 5.2±4.4 kg (p<0.001), and body mass index decreased from 30.6±6.5 kg/m² to 28.8±5.7 kg/m² (p<0.001). No significant changes were observed in lipids or blood pressure. Regression analyses showed an association between weight loss and HbA1c normalisation (OR 1.413, p=0.002), but no relationship was found between carbohydrate intake and changes in HbA1c. Qualitative interviews revealed that motivation and empowerment were central to adherence; participants cited health improvements and reduced medication as key motivators. Challenges included social dynamics and domestic routines; older participants and those with significant comorbidities reported greater difficulties in maintaining the diet. Conclusions CRD was associated with reduced HbA1c and weight. Weight loss was associated with HbA1c normalisation; however, no independent statistical relationship was observed between carbohydrate reduction and glycaemic outcomes. HbA1c normalisation often occurred with LCD, suggesting it is a viable option for individualised care alongside other dietary approaches in T2D.

Introduction Diabetes mellitus is involved in the development of various diseases, including microvascular and macrovascular complications, infections, osteoporosis and dementia. This study aimed to evaluate the mediating role of obesity or metabolic abnormalities (hypertension, dyslipidaemia) in causal pathways between dietary habits (fast eating, skipping breakfast) and developing type 2 diabetes. Research design and methods A retrospective cohort study was conducted using health examination data from employees of Panasonic Corporation in Japan. Information on participants’ dietary habits, metabolic factors and the onset of diabetes was collected. Cox regression-based causal mediation analyses were performed to assess associations among dietary habits, metabolic factors and diabetes development. Results Among 155 963 participants, fast eating (HR 1.93, 95% CI 1.73 to 2.14) and skipping breakfast (HR 1.31, 95% CI 1.24 to 1.37) were associated with increased onset of type 2 diabetes within 13 years. Fast eating showed a strong association with diabetes risk mediated through body mass index (BMI) (proportion mediated 0.73, 95% CI 0.65 to 0.85) while skipping breakfast showed a direct association with diabetes risk not mediated through BMI (proportion mediated 0.10, 95% CI 0.07 to 0.14). Both dietary habits exhibited small mediating effects through hypertension or dyslipidaemia. Conclusions Fast eating increases diabetes risk, primarily through BMI, whereas skipping breakfast poses a risk not through BMI. These findings suggest a mechanism by which dietary habits affect glucose metabolism.

Background The variability in lactose digestion ability is categorised into lactase persistence and lactase non-persistence phenotypes, primarily determined by the 13 910 C>T single nucleotide polymorphism (rs4988235). The relationship between the lactase gene, obesity and milk consumption has been studied, but the result remains discrepant. We aimed to investigate the association between lactase phonotypes/genotypes and obesity while also exploring potential connections with metabolic syndrome and milk consumption. Objective To investigate the association between lactase phenotypes/genotypes and 1) body mass index, 2) obesity/overweight status, 3) metabolic syndrome and 4) milk consumption. Methods A systematic literature search of Medline (via PubMed search engine) and Scopus databases was conducted up to August 2023. Data extraction was performed independently by three investigators. Meta-analysis utilised fixed and random effects, with heterogeneity assessed using Higgin’s I² statistic. Publication bias was examined using funnel plots. Results Twenty-six studies were included (5 in children, 21 in adults). In children, body mass index did not significantly differ based on the lactase phenotypes (mean difference 0.17 kg/m², 95% CI −0.26 to 0.60; p=0.44 (three studies)). However, among adults, lactase persistence individuals had a higher body mass index (mean difference 0.22 kg/m², 95% CI 0.15 to 0.30; p<0.01 (19 studies)) and an increased risk of obesity/overweight by 27% (OR 1.27, 95% CI 1.07 to 1.52; p=0.01 (four studies)) as compared with the lactase non-persistence. Even though it was not associated with metabolic syndrome (OR 0.98, 95% CI 0.61 to 1.57; p=0.93 [three studies]), lactase persistence was associated with higher milk consumption (mean difference of 41 g/day, 95% CI 26 to 56, p<0.01 [six studies]). Conclusions While data on lactase phenotype and obesity in children are limited, adults with lactase persistence have higher body mass index and risk of obesity/overweight and greater milk consumption than lactase non-persistence. More research is needed to define the interplay between lactase genotypes/phenotypes, obesity and milk consumption. PROSPERO registration number CRD42023400753.

Background While body mass index (BMI) is widely used to assess obesity, it fails to detect individuals with normal weight who have excess body fat referred to as normal weight obesity (NWO). NWO is associated with an increased risk of cardiometabolic conditions despite a seemingly healthy BMI. South Asians, known to carry higher fat percentages at lower BMI levels, are particularly susceptible. Yet, population-based data on the prevalence and determinants of NWO in North India are limited. Objectives To estimate the prevalence and examine the determinants of NWO among adults in Kurukshetra, North India, using Asian BMI criteria and body fat percentage. Methods A community-based cross-sectional study was conducted from October 2022 to September 2023, involving 460 adults aged 20–60 years from urban (Shahabad) and rural (Thol) areas of Kurukshetra district, selected via multistage stratified random sampling. NWO was defined as BMI 18.50–22.99 kg/m² with body fat >25% in males and >30% in females, measured using an Omron body fat analyser. Data on sociodemographic, dietary, physical activity and sleep variables were collected using a pre-tested structured questionnaire. Associations were analysed using χ2 tests and multivariate logistic regression. Results NWO was identified in 24.6% of participants with normal BMI. The condition was more prevalent among females (27.6%) and increased notably with age, particularly after 40 years. Married individuals were more frequently affected. Protective factors included daily intake of fruits and vegetables, greater dietary diversity and moderate-to-high physical activity. Poor sleep hygiene, particularly prolonged sleep latency and short sleep duration, was also significantly associated with NWO. These findings suggest a hidden metabolic risk among individuals with otherwise ‘normal’ weight. Conclusion NWO poses a significant but under-recognised public health challenge. Routine screening should include body fat assessments alongside BMI to enable early lifestyle interventions and prevent non-communicable diseases.

Background Given the anti-inflammatory properties of nuts, their consumption might play a role in reducing inflammation and the severity of pemphigus vulgaris (PV). However, limited evidence exists regarding the association between nut intake and PV severity. Thus, this cross-sectional study investigates the relationship between PV severity and the consumption of total nuts as well as specific nut varieties. Methods This study included 138 PV patients, of whom 108 had a Pemphigus Disease Area Index (PDAI)<15 and 30 had a PDAI≥15. Dietary intake was evaluated using a validated 168-item food frequency questionnaire, and consumption of total nuts and subtypes (peanuts, hazelnuts, almonds, walnuts and pistachios) was categorised into quartiles. Results While no significant association was found between individual nut types and PV severity, individuals with the highest total nut intake (including peanuts, hazelnuts, almonds, walnuts and pistachios) were 92% less likely to experience increased PV severity compared with those with the lowest intake (OR: 0.08; 95% CI 0.01 to 0.38). This association remained significant after adjusting for age, sex and energy intake (OR: 0.072; 95% CI 0.01 to 0.36). Further adjustments for corticosteroid use and physical activity did not alter the strength or significance of the association (OR: 0.08; 95% CI 0.01 to 0.42). Conclusion Our findings suggest that higher total nut consumption is inversely associated with PV severity, though no such link was observed for specific nut subtypes. Prospective cohort studies are needed to validate these results.