Background: It is widely accepted that low-grade chronic inflammation in obesity worsens the metabolic state and threatens patients’ lives in a long-term manner. In fact, diet therapy is the first-line treatment in which relevant nutrients such as the omega-3 polyunsaturated fatty acids (ω-3 PUFA) must be adequately consumed to counteract the established inflammation. In particular, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have been identified as agonists of cellular receptors, including the free fatty acid receptor 4 (FFAR4), which regulates anti-inflammatory pathways associated with enhanced insulin sensitivity. However, the expression and activation of this receptor in peripheral blood mononuclear cells (PBMC) remains poorly investigated in humans. Objective: This study aimed to evaluate the effect of a diet supplemented with marine ω-3 PUFA on FFAR4 receptor activation and inflammatory markers in peripheral blood mononuclear cells in subjects with obesity. Methodology: A double-blind, randomized clinical trial (NCT05068557) was conducted over two months (eight weeks) in 55 obese individuals (aged 25–59 years). Participants were randomly assigned to one of two groups: an active placebo group (1.6 g/day of alpha-linolenic acid) or a marine ω-3 group (1080 mg of EPA and 720 mg of DHA). Both groups followed a dietary regimen with progressive calorie restriction (−200 kcal/day during weeks 0–4 and −400 kcal/day during weeks 4–8) in addition to supplementation. Results: Following the intervention, both groups showed significant improvements in body composition and biochemical parameters. Supplementation with EPA and DHA enhanced FFAR4 activation at the end of the intervention. Moreover, there was a reduction in the expression of JNK and IKKβ genes, as well as in serum levels of TNF-α, IL-6, and IL-18. In contrast, IL-10 levels increased significantly both within and between the groups. Conclusions: Marine ω-3 PUFA supplementation, in the context of a dietary intervention, promotes FFAR4 activation, thereby contributing to the modulation of the inflammatory response in human PBMC.

Neck circumference (NC) and wrist circumference (WrC) have been proposed as practical and inexpensive tools with the capacity to indicate metabolic alterations to some extent. Nevertheless, their application in the pediatric population is relatively recent. Thus, the aim of this scoping review was to review and analyze the reported evidence regarding the correlation of NC and WrC with metabolic alterations in the pediatric stage. The literature search was performed in January 2021 in seven indexes and databases. A total of 26 articles published between 2011 and 2020 were included. Most significant results were grouped into three categories: serum lipid profile, glucose homeostasis, and blood pressure. The parameter that showed the most significant results regardless of the anthropometric indicator analyzed for association was blood pressure. In contrast, total cholesterol and LDL-cholesterol showed non-significant associations along with conflicting results. We conclude that the use of NC and WrC, in addition to other well-established indicators, could facilitate the identification of metabolic alterations, specifically in plasma insulin and blood pressure. In fact, further studies are required to address the potential use of NC and WrC as predictors of early metabolic alterations, especially in countries with a fast-growing prevalence in obesity.

Neck circumference was studied for the first time in a pediatric population in 2010. Since then, various countries have proposed cutoff values to identify overweight, obesity, and metabolic syndrome. However, no reference values have been established for the Mexican child population. The aim of this study is to provide percentile reference values for the neck circumference of Mexican schoolchildren. Only normal-weight schoolchildren aged 6–11 years were included. Percentiles and growth charts were constructed based on the “Generalized Additive Model for Location, Scale and Shape” (GAMLSS). A total of 1059 schoolchildren (52.9% female) was evaluated. Weight, height, and BMI values were higher for males; however, this difference was not statistically significant. The 50th percentile for females was 24.6 cm at six years old and 28.25 cm at 11 years old, and for males, it was 25.75 cm and 28.76 cm, respectively. Both males and females displayed a pronounced increase in neck circumference between 10 and 11 years of age. The greatest variability was found in the 11-year-old group, with an increase of 5.5 cm for males and 5.4 cm for females. This study presents the first reference values for neck circumference for a Mexican child population.

Background/Objectives: Neck circumference (NC) has been proposed as a simple measurement to identify patients with overweight and obesity. It has been found that adipose tissue at the cervical level is associated with the presence of metabolic alterations. The aim of this study was to estimate the association between NC and indicators of Metabolic Syndrome (MS) to subsequently estimate its capacity to identify the risk of MS compared to waist circumference (WC) and Body Mass Index (BMI). Methods: A cross-sectional study was carried out with a sample of 286 children 6–9 years old who attended six public primary schools in Jalisco, Mexico. Pearson’s correlation coefficients along with sensitivity and specificity tests were performed to analyze the relationship between NC and MS indicators. Odds ratio (OR) and concordance analyses were performed considering the Kappa index. Results: NC showed statistically significant correlations with all MS indicators except for LDL cholesterol and total cholesterol. The cut-off points of NC to identify MS according to sex was >27.4 cm for girls and >29.8 cm for boys. The association of NC with values above the cutoff point and the presence of MS was OR: 21.6 (CI: 7.11–65.74). Conclusions: NC represents a simple and cost-effective alternative to identify children at risk of MS when compared to BMI and WC.

Background: Neck circumference (NC) is a simple anthropometric index of upper-body subcutaneous adiposity. Its relationship with inflammatory cytokines, particularly the anti-inflammatory cytokine IL-10, remains poorly explored, especially in Latin-American populations. Methods: This cross-sectional study analyzed data from 80 Mexican adults with obesity (40 women and 40 men). NC, waist circumference (WC), and body mass index (BMI) were measured according to standardized ISAK and NHANES protocols. Fasting glucose, insulin, lipid profile, and HbA1c were evaluated. Finally, serum TNF-α, IL-6, IL-18, IL-10, and hs-CRP were quantified from a subsample. Correlation coefficients and sex-stratified multiple linear regression models adjusted for age and BMI were performed. Results: In the overall sample, neck circumference (NC) was positively associated with triglycerides, VLDL-C, insulin, and HbA1c, and inversely associated with HDL-C. Sex-stratified analyses revealed marked differences. In women, NC showed strong and independent associations with triglycerides, VLDL-C, IL-10, and the IL-10/TNF-α ratio, whereas these associations were not observed in men. Similarly, waist circumference was independently associated with IL-10, and BMI was associated with hs-CRP. Conclusions: NC may serve as a useful surrogate marker of upper-body adiposity and is independently associated with triglycerides, VLDL-C, IL-10, and the IL-10/TNF-α ratio exclusively in women with obesity. These exploratory findings highlight sex-specific differences in the adiposity–inflammation axis and underscore the need for larger longitudinal studies and sex-tailored approaches in obesity research.