Obesity is a multifactorial condition arising from complex interactions between genetic susceptibility, environmental exposures, and behavioural factors. Among the genetic contributors identified through genome-wide association studies, variants within the fat mass and obesity-associated (FTO) gene represent some of the most consistently replicated loci associated with body mass index, adiposity, and appetite regulation across populations. Experimental and observational evidence suggests that FTO variants may influence energy intake, food preference, and metabolic pathways through effects on hypothalamic signalling, adipocyte biology, and epigenetic regulation. These findings have stimulated interest in precision nutrition approaches that aim to tailor dietary strategies according to individual genetic profiles. This narrative review critically examines the role of FTO gene variants in polygenic obesity and evaluates the current evidence supporting gene-diet interactions relevant to personalized weight management. We synthesized data from mechanistic studies, observational cohorts, randomized controlled trials, and meta-analyses to assess whether dietary interventions, including macronutrient composition, mediterranean-style dietary patterns, and discretionary food intake, can meaningfully modify obesity risk in individuals carrying FTO risk alleles. While mechanistic plausibility and observational associations are well established, evidence from intervention studies indicates that genotype-specific responses are generally modest and context-dependent. Overall, current findings support the potential of precision nutrition as a complementary framework rather than a deterministic approach to obesity management. Further large-scale, long-term, and ethnically diverse intervention studies are required to clarify clinical utility and inform evidence-based implementation.

A high sodium intake is a major risk factor for raised blood pressure. Consumption of fish fillet is associated with lower blood pressure in humans and other animals, whereas the effects of consuming fish residuals are less explored. To obtain high-quality fishmeal with acceptable sensory properties, the fish residuals may be washed with seawater onboard factory trawlers. This will increase the sodium content in the residuals, and whether this affects blood pressure has not yet been investigated. The primary objective of the present study was to investigate if the increased sodium content in Atlantic cod (Gadus morhua) residuals after washing with saltwater affected the development of high blood pressure in male obese Zucker fa/fa rats which spontaneously develop hypertension. Rats were fed diets containing cod protein powders prepared from unwashed or saltwater-washed backbone or head fractions (n 6/group) as 25% of total protein with the remaining 75% as casein, or casein as the sole protein source (Control group, n 6) for six weeks. Blood pressure was measured on day 0 and 40. The diets containing backbone protein powder, independent of whether this fraction was washed with saltwater or not, attenuated the blood pressure increase compared to the Control group, whereas diets containing washed or unwashed head protein powder did not affect the blood pressure development. To conclude, a diet containing cod backbone protein powder attenuated the blood pressure increase in obese Zucker fa/fa rats, and this effect was not compromised by the higher sodium content in backbones washed with saltwater.

The role of omega-6 polyunsaturated fatty acids (PUFAs), especially linoleic acid (LA) in adiposity, remains contested. While clinical interventions suggest improved body composition with higher LA intake, observational evidence using dietary data is inconsistent, and few studies consider circulating fatty acids or longitudinal changes in adiposity. Using multivariable linear models, we evaluated cross-sectional and longitudinal associations between omega-6 PUFAs and waist circumference (WC), weight, and whole-body fat mass (FM) in the UK Biobank Cohort. Cross-sectionally (N=272,587, 54% female, mean age 57 years), higher circulating LA was inversely associated with WC, weight, and FM. Participants in the highest versus lowest quintile of LA had significantly smaller WC [–11.04 (–11.17, –10.91) cm], lower weight [–11.77 (–11.92, –11.62) kg], and lower FM [–7.87 (–7.97, –7.77) kg]. Associations for total omega-6 were generally consistent with those for LA. Conversely, non-LA omega-6 was positively associated with WC [1.46 (1.32, 1.61) cm], weight [2.41 (2.25, 2.58) kg], and FM [1.81 (1.69, 1.92) kg]. Longitudinal analyses (N=58,335, 51% female, mean age 55 years) largely corroborate these patterns, with annual changes in WC, weight, and FM inversely associated with LA and positively associated with non-LA omega-6. Higher circulating LA, but not non-LA omega-6, was associated with lower WC, weight, and FM both cross-sectionally and longitudinally. Our findings potentially support dietary recommendations to promote LA-rich oils. Divergent associations between LA and non-LA omega-6 caution against treating omega-6 PUFAs as a homogenous group. Examining distinct health effects of individual non-LA omega-6 are warranted.

Disordered eating (DE) is common among patients attending primary health care settings. However, the prevalence of DE among patients who receive care in nutrition practice settings has yet to be estimated. We aimed to determine the prevalence of DE and its correlates among outpatients in a nutrition service. A cross-sectional survey was conducted using a convenience sample of outpatients (N = 502) who received care from 2022 to 2024 at the Nutrition Care Offices, which is a university nutrition service in Mexico City. A screening questionnaire was created to identify DE. Items were derived from existing DE screening tools and patients’ experiences. Linear regression models were estimated, with the outcomes being the three indicators of DE (negative body image, binge eating-compensation, and exercise as a negative experience). The most common DE behaviours and cognitions were feeling uncomfortable or insecure about their body fat (74.7%), feeling ashamed of their weight (57.6%), feeling uncomfortable or insecure about their muscles (57.2%), feeling bad when their weight is measured (54.0%), and feeling they have lost control of what they eat (51.0%). Binge eating-compensation and negative body image scores were higher among women, younger individuals, those with higher body weight, and those with very light or light leisure-time physical activity (PA). The practice of leisure-time PA was positively associated with exercise as a negative experience but negatively related to negative body image. Our findings suggest that DE is a problem that arises recurrently in weight-related nutrition consultations. Higher risk groups deserved special attention.

School-based interventions offer a promising setting to promote healthier nutritional behaviours (NB) such as physical activity (PA), sedentary behaviour (SB) and eating behaviour, while addressing weight social inequalities. NB changes may occur before measurable effects on weight, which can take longer to emerge. This study evaluated the overall effectiveness of the school-based Promotion de l’ALIMentation et de l’Activité Physique – INEgalités de Santé (PRALIMAP-INÈS) trial on weight and NB social inequalities reduction among adolescents with overweight or obesity. Adolescents were divided into two intervention groups according to their socio-economic status (socially advantaged and socially less advantaged). NB were self-reported by adolescents. Outcomes were BMI z-score (BMIz), fruit and vegetables (FV) consumption, sweetened products and beverages (SPB) consumption, vigorous/moderate PA, walking and SB. Overall effectiveness was estimated using generalised pairwise comparisons, estimating net benefit for each outcome (δ) and overall net benefit (Δ). Of 985 adolescents (age = 15·3 (sd 0·7 years; 46·7 % boys), those in less advantaged group were 12·5 % more likely to have a favourable change in weight status and NB than those in advantaged group (Δ = 12·5 % (6·1, 19·1 %)). For each outcome, net benefits were as follows: BMIz (δ = 4·2 % (0·0, 8·6)), vigorous PA (δ = 4·2 % (0·4, 8·3)), FV (δ = 3·2 % (0·9, 5·5)), SB (δ = 0·8 % (–1·6, 3·2)), SPB (δ = −0·2 % (–1·1, 0·6)), moderate PA (δ = 0·2 %) (–0·7, 1·1) and walking (δ = 0·2 % (–0·2, 0·6)). Results showed an overall beneficial effect of the PRALIMAP-INÈS trial in reducing social inequalities in weight and NB among adolescents with overweight or obesity. Long-term effectiveness could be expected by reducing social inequalities in NB.

The potential of obesity medications to serve as viable alternatives to bariatric surgery to treat obesity remains an open question. This review examines whether contemporary anti-obesity pharmacotherapy can replace metabolic and bariatric surgery in the management of obesity, by critically comparing their mechanisms of action, weight loss outcomes, durability, safety profiles and roles in long-term disease control. While metabolic/bariatric surgery has been the gold standard for substantial and sustained weight loss, advancements in pharmacotherapy are producing weight loss approaching surgical outcomes without associated risks, complications and recovery time. New drug therapies demonstrate previously unattainable efficacy and long-term control of obesity. Surgery, however, induces superior short- and long-term weight loss via profound hormonal, neurological and metabolic shifts, resulting in durable outcomes without ongoing intervention, though it remains difficult to scale. Pharmacotherapy is scalable and increasingly effective but requires sustained adherence, with loss of treatment-mediated control and weight regain upon cessation. It also does not have as extensive established research on safety as surgery. While obesity medications cannot fully replicate the multifactorial physiological impacts of metabolic/bariatric surgery, they offer a scalable, less invasive treatment path that broadens patient options. So far, pharmacotherapy will not replace surgery, as there are patients who will respond better to it, while others to medication only. However, combining both surgical and pharmacological options can increase the penetrance of treatments to manage the chronic complexities of obesity.

Children with CHD have demonstrated a rise in obesity, and have unique risks related to comorbidities of obesity, including feeding dysfunction and exercise limitations. The incidence and cause of obesity among patients with surgically corrected CHD are not fully understood. This single-centre, longitudinal, retrospective cohort study identified patients between 2004 and 2020 with surgical correction. Diagnoses were restricted to d-transposition of the great arteries, coarctation of the aorta, or tetralogy of Fallot with surgical repair by 6 months of life without long-term post-operative complications or chromosomal abnormalities. Evaluation of Body Mass Index by survival curve for endpoints of overweight and obesity, as well as descriptive analysis of the population, was performed compared to the expected prevalence in the state of Oregon (13.7%). Cohorts were divided into eras in 5-year increments. Of 240 patients identified, 87 (36.2%) were overweight and 50 (20.8%) obese, findings significantly higher than expected prevalence (p = <0.01) for the same time period in the state of Oregon. Patients with coarctation of the aorta had a higher prevalence than other diagnoses (p = <0.01). Patients in the 2004–2008 cohort had the highest rates of obesity compared to other cohorts (p = <0.01 and p = <0.01, respectively), likely due to a longer observational period. However, the 2014–17 cohort had the highest rate of increase in hazard ratio. Children with surgically corrected CHD demonstrate higher prevalences of obesity compared to the general population. There is variation by diagnosis, with coarctation of the aorta having comparatively higher prevalences of obesity. Several factors may impact this discrepancy, including sports participation restrictions and initial emphasis on weight gain.

Studies frequently view Black populations as homogenous, disregarding important diversity within this population. Furthermore, nativity can be key to distinguishing health risks among this population. Yet few researchers have examined these distinctions using body roundness index (BRI), a measure of central adiposity. We assessed the relationship between nativity and BRI among non-Hispanic Black people in the United States (US) using cross-sectional data from the 2011–2018 National Health and Nutrition Examination Survey (NHANES). BRI was calculated using height, weight, and waist circumference. Nativity was categorized as US-born and foreign-born. Multilinear regression analysis was used to evaluate the relationship between BRI and nativity, controlling for demographic characteristics and Healthy Eating Index scores. The average age and BRI score of participants were 44.74 ± 0.46 and 5.36 ± 0.04, respectively. Among eligible participants (3341), 9.6% were foreign-born (n = 322). In multivariate regression models adjusting for covariates, men had significantly lower BRI scores than women (4.67 ± 0.04 versus 5.96 ± 0.05; β = −1.25; t61 = 24.60; P < 0.0001), and BRI increased with age (β = 0.02; t61 = 9.17; P < 0.0001). US-born Black people had significantly higher BRI scores compared to their foreign-born counterparts (5.40 ± 0.04 versus 5.00 ± 0.09; β = −0.36; t61 = −3.99; P = 0.0002). Results suggest that nativity is associated with central adiposity, with potential implications for cardiometabolic disease risk.

Understanding trends in height and BMI, along with trajectories of weight status, is crucial to identifying the optimal timing for intervention. The objective of this study was to describe trends in height and BMI among children and adolescents and identify the trajectory of weight status over time. This was a longitudinal study with data collected annually (2013–2020). A total of 41 325 students aged 5–18 years from forty-seven schools participated in the study, and a subsample of 11 535 participants with at least five BMI measurements was used for the analyses. Mixed-effects analysis showed significant increases in height over the years for boys (0·19 cm, standard error 0·01, P < 0·001) and girls (0·15 cm, standard error 0·01, P < 0·001). Regarding BMI, an increasing trend over the years was also found in boys (0·04 kg/m2, se 0·01, P < 0·001) and girls (0·04 kg/m², se 0·01, P < 0·001). Analysing weight status trajectories, three groups were identified: consistently normal weight (males 63·7 %, females 64·5 %), increasingly overweight (males 21·8 %, females 20·7 %) and increasingly obese (males 14·5 %, females 14·8 %). We conclude that in adolescence, height was below expected, indicating that children are not reaching their maximum growth potential. Furthermore, the identification of increasing trajectories of overweight and obesity, starting in childhood, emphasises the progressive nature of excessive weight gain before adulthood. These findings highlight the early onset of nutritional deviations in this population, suggesting the need for interventions to promote healthy weight as children transition into adolescence to mitigate future health risks.

Food insecurity (FI), defined as unreliable access to healthy, nutritious food, is a major health concern in higher-income countries, primarily due to its association with an increased risk of obesity. Supermarket-based interventions may influence population-level food purchasing behaviour, an antecedent to consumption. It is unclear whether there are specific characteristics that these interventions should employ to resonate with vulnerable groups. This scoping review aimed to explore the characteristics of supermarket-based interventions that sought to support healthier and/or more environmentally sustainable food purchasing for people living with obesity, overweight (PLWO/Ow), and/or FI.

A systematic literature search, conducted in Medline, Embase, CINAHL, Scopus, and Web of Science databases, identified 35 eligible studies, representing 43 interventions. Title and abstract screening and data extraction were conducted independently by two reviewers. Most interventions focused on supporting the purchase of healthy food items. No study applied a validated measure of FI. Area-level demographic data were used to identify FI-related characteristics (i.e., area of low income, low socio-economic status) and, in some cases, those living with obesity. Interventions utilised the behaviour change levers of price (n = 8), promotion (n = 2), placement (n = 7), nudges (n = 4), and education (n = 2), or a combination of these (n = 20). High heterogeneity in the way behavioural change levers were operationalised and combined, alongside the use of proxy measures to identify FI and PLWO/Ow, makes it difficult to determine the most supportive intervention characteristics. This presents challenges in understanding how to best facilitate changes in purchasing patterns in favour of heathy, sustainable food items in this population.

The effect of dietary intake on body weight may vary based on individual genetic differences. However, children are rarely used in such investigations. The aim was to identify possible genetic moderation through polygenic scores (PGS) for BMI, of the association between dietary intakes and BMI in children. The study sample included children who were part of a French-Canadian birth-cohort study. BMI data was available on seven occasions between ages 4 and 13 years. FFQ (juice and fruit drinks, sweets and snack foods, meats, and fruits and vegetables) and 24-h dietary recall (proteins, lipids, carbohydrates, total energy) data were available up to 4 years. Linear mixed models were used to account for repeated BMI measurements. The consumption of juice and fruit drinks (in girls), sweets and snack foods, fruits and vegetables, proteins, lipids, carbohydrates and total energy were associated with BMI. Associations with BMI increased with age (kg/m2 per year) for fruits and vegetables (β: −0.03, 95%CI: −0.06;−0.01), lipids (β: 0.11, 95%CI: 0.01;0.22), carbohydrates (β: 0.05, 95%CI: 0.01;0.08), and total energy (β: 0.07, 95%CI: 0.02;0.12), and with higher values of a PGS (kg/m2 per SD) for proteins (β: 0.54, 95%CI: 0.03;1.06), lipids (β: 0.63, 95%CI: 0.12;1.13), and total energy (β: 0.32, 95%CI: 0.06;0.58). Using longitudinal data, we showed that the associations between specific dietary intakes and BMI may vary depending on age and genetic susceptibility in childhood.

Epidemiological and clinical research has confirmed a link between obesity and depressive symptoms, with inflammation as a potential common mechanism. Given that dietary components modulate inflammation and relate to both conditions, investigating dietary inflammation as a potential underlying pathway is necessary. Herein, we aimed to explore the potential role of the Energy-adjusted Dietary Inflammatory Index (E-DII) in explaining the relationship between obesity and depressive symptoms. We conducted a cross-sectional analysis of the 2007–2018 National Health and Nutrition Examination Survey cohort, enrolling 20 324 participants. Obesity and dietary inflammation were assessed by BMI and E-DII, respectively. Depressive symptoms were evaluated using the nine-item Patient Health Questionnaire-9. We found that obesity and inflammatory diets were positively associated with depressive symptoms (β = 0·50, 95 % CI 0·30, 0·69; β = 0·35, 95 % CI 0·19, 0·50; both P < 0·001), and variations in the association among obesity, pro-inflammatory diets and depressive symptoms were evident across various population subgroups (e.g. sex, age, chronic diseases and smoking status subgroups, Pfor interaction < 0·050). After adjusting for all covariates, E-DII accounted for 4 % of the obesity–depression association. Despite this modest proportion, the finding identifies dietary-induced inflammation as a statistically significant, modifiable pathway. In conclusion, obesity and pro-inflammatory diets are linked to an increased risk of depressive symptoms, with E-DII serving as a modest but significant modifiable pathway. These findings highlight dietary intervention as a potential strategy for mitigating depressive symptoms in individuals with obesity.