The objective of this study was to assess the feasibility and effectiveness of a novel WeChat applet-based personalized dietary intervention aimed at promoting healthier dietary intakes. A two-arm parallel, randomized, controlled trial was conducted in a real-world scenario and involved a total of 153 participants (the intervention group, n = 76; the control group, n = 77), lasting for 4 months in Shanghai, China. The intervention group had access to visualized nutrition evaluations through the applet during workday lunch time, while the control group received no interventions. A total of 3413 lunch dietary intake records were captured through the applet. Linear mixed models were utilized to assess the intervention effects over time. At baseline, the participants’ lunchtime dietary intakes were characterized by insufficient consumption of plant foods (86.9% of the participants) and excessive intake of animal foods (79.7% of the participants). Following the commencement of the intervention, the intervention group showed a significant decrease in the animal/plant food ratio (β = −0.03/week, p = 0.024) and the consumption of livestock and poultry meat (β = −1.80 g/week, p = 0.035), as well as a borderline significant increase in the consumption of vegetables and fruits (β = 3.22 g/week, p = 0.055) and plant foods (β = 3.26 g/week, p = 0.057) over time at lunch compared to the control group. The applet-based personalized dietary intervention was feasible and effective in improving dietary intakes and, consequently, possibly may manage body weight issues in real-world scenarios.

Background: Metabolic syndrome, a cardiovascular risk cluster, is recognized as a global health priority influenced by gene–diet interactions. The rs2794720 polymorphism has not been previously reported in relation to metabolic syndrome. This study examined the associations between dietary iron, SNP rs2794720, and metabolic syndrome in Chinese metropolitan population, with a focus on sex-specific and genotype-specific effects. Methods: A community-based cross-sectional study enrolled 2639 adults (1254 males, 1385 females) from Shanghai, China. Anthropometric measurements, laboratory analyses, and genotyping for the participants were performed. Dietary assessment utilized the 3-day 24 h dietary recall method. Metabolic syndrome was identified by the presence of at least three out of five metabolic abnormalities according to the NCEP—ATP III criteria. Results: After adjusting for confounders, in males, metabolic syndrome risk was associated with dietary iron (p = 0.002) but not with rs2794720 (p = 0.731). In females, metabolic syndrome risk was associated with rs2794720 (p = 0.014) and dietary iron (p = 0.016), with a significant interaction observed between rs2794720 and dietary iron (p = 0.047). Stratified by rs2794720, among females lacking the C allele, there was a linear trend between dietary iron and metabolic syndrome risk (p = 0.048). Compared to the reference group (lowest-intake GG homozygotes), the Q2–Q4 Ors (95% CI) were 5.31 (1.08, 39.52), 5.50 (1.16, 40.28), and 8.40 (1.80, 41.44)), while the major allele carriers did not show this trend (p = 0.704); compared to the reference group, the Q1–Q4 ORs(95% CI) were 6.13 (1.68, 39.66), 7.53 (2.06, 48.86), 8.10 (2.20, 52.60), and 7.84 (2.07, 51.70)). Conclusions: Our study first identified rs2794720 as a novel SNP associated with metabolic syndrome in Chinese females. The association between dietary iron and metabolic syndrome risk was unique to GG homozygotes (the minority), whereas CC/CG genotypes (the majority) showed no such association.

Objectives: Dysglycemia is prevalent in China; previous studies had shown that dietary iron was associated with glucose metabolism, and rs864745 was also related to it. The objective of this study is to investigate the association between dietary iron, the SNP of the JAZF1 rs864745, and glucose metabolism among Chinese adults. Methods: 3298 participants (1584 males and 1714 females) were recruited and underwent physical measurements, laboratory tests, and genotyping. All surveys were conducted by qualified public health professionals. Dietary iron was assessed using the 3-day 24 h dietary recall method and condiment weight records. Genotyping for rs864745 was performed using the SNaPshot Multiplex System. Results: After adjusting for covariates, a significant trend was found between the dietary iron and elevated fasting glucose (p = 0.012), whereas no such trend was observed for the rs864745 (p = 0.932). Among the male participants, the risk of elevated fasting glucose was associated with both dietary iron (compared to the lowest quartile, the ORs with 95% CIs for elevated fasting glucose in Q2,Q3, and Q4 were 1.52 (1.01, 2.45), 1.73 (1.05, 3.00), and 2.49 (1.33, 4.74), respectively) and the rs864745 (OR = 2.15 (1.02, 4.51)), and an interaction effect between them was observed (p = 0.041), which was absent in females (p = 0.999 and p = 0.131, respectively). Stratified by the SNP rs864745, the males without the C allele had a linear risk increase with iron (p = 0.018), while the C allele carriers did not. Additionally, ferritin and the rs864745 were associated with the AST-to-ALT ratio (p = 0.005 and p = 0.048, respectively). Conclusions: Our study found that dietary iron and the SNP rs864745 interacted and were associated with elevated fasting glucose in Chinese males and absent in females. In addition, the presence of a C allele on rs864745 showed higher risks of elevated fasting glucose regardless of the consumption of dietary iron among the males.

Background/Objectives: Although efficacious in randomized trials, the real-world adoption of AI-driven dietary management applications remains uncertain across diverse dining contexts and populations. Methods: This field-based observational study was conducted over 18 days at three real-world dining sites in Shanghai, China, enrolling 181 participants stratified into three groups based on food service style and customer attribute. A cross-sectional survey was administered on day 9, followed by a 9-day prospective usage tracking period. Results: After adjusting for sex, Group 2 (staff cafeteria with fixed-portion dishes) had the highest adjusted mean usability score at 71.20 (p < 0.001). Group 3 (community canteen) had the highest mean scores for information quality (16.57, p = 0.03) and perceptions of intended use in nutrition (12.01, p = 0.08). However, Group 3 recorded zero active usage sessions despite favorable initial perceptions. Conclusions: Favorable user perceptions of this AI-driven dietary management tool did not automatically translate into adoption. Scenario-specific usability and digital divide constraints define the boundary of real-world efficacy; moreover, AI may amplify existing dietary self-management behaviors rather than creating them de novo.