Background/Objectives: Primary dysmenorrhea (PD) is a common condition affecting up to 90% of menstruating women, which often results in significant pain without an underlying pathology. Zinc, recognized for its anti-inflammatory and antioxidant effects through inhibiting prostaglandin production and superoxide dismutase 1 (SOD1) upregulation, alleviates menstrual pain by preventing uterine spasms and enhancing microcirculation in the endometrium, suggesting its potential as an alternative treatment for primary dysmenorrhea. The goal of this systematic review and meta-analysis was to assess the efficacy and safety of zinc supplementation in reducing pain severity among women with PD and to explore the influence of dosage and treatment duration. Methods: Following the PRISMA 2020 guidelines, we conducted an extensive search across databases such as PubMed, Embase, Cochrane Library, Web of Science, and Google Scholar, up to May 2024. Randomized controlled trials assessing the effects of zinc supplementation on pain severity in women with PD were included. Pain severity was evaluated with established tools, such as the Visual Analog Scale (VAS). Risk of bias was assessed using the Cochrane Risk of Bias 2 (RoB2) tool. Two reviewers independently performed the data extraction, and a random-effects model was used for meta-analysis. Meta-regressions were conducted to examine the influence of zinc dosage and treatment duration on pain reduction. Adverse events were also analyzed. Results: Six RCTs involving 739 participants met the inclusion criteria. Zinc supplementation significantly reduced pain severity compared to placebo (Hedges’s g = −1.541; 95% CI: −2.268 to −0.814; p < 0.001), representing a clinically meaningful reduction in pain. Meta-regression indicated that longer treatment durations (≥8 weeks) were associated with greater pain reduction (p = 0.003). While higher zinc doses provided additional pain relief, the incremental benefit per additional milligram was modest (regression coefficient = −0.02 per mg; p = 0.005). Adverse event rates did not differ significantly between the zinc and placebo groups (odds ratio = 2.54; 95% CI: 0.78 to 8.26; p = 0.122), suggesting good tolerability. Conclusions: Zinc supplementation is an effective and well-tolerated option for reducing pain severity in women with primary dysmenorrhea. Doses as low as 7 mg/day of elemental zinc are sufficient to achieve significant pain relief, with longer durations (≥8 weeks) enhancing efficacy. The favorable safety profile and ease of use support the consideration of zinc supplementation as a practical approach to managing primary dysmenorrhea.

The effect of a vegetarian diet on bone health remains controversial. This retrospective medical record review compared changes in bone mineral density (BMD) and trabecular bone score (TBS) between vegetarian and non-vegetarian middle-aged and older women who underwent two general health examinations (T1 and T2) that were approximately three years apart. Generalized estimating equations were used to compare the change in lumbar spine and bilateral hip BMD and TBS over time. At T1, the mean age of the patients was 56.6 years (standard deviation 9.7 years) and the mean interval between T1 and T2 was 2.7 years. For women aged 40–55 years, compared with non-vegetarians, vegetarians were significantly associated with a larger reduction in lumbar spine BMD (p < 0.001) and left hip femoral neck BMD (p = 0.015) over the three-year interval. On the contrary, changes in BMD were not significant at any site in women aged ≥ 56 years. Moreover, the changes in BMD and TBS over the three-year interval did not significantly differ between vegetarian and non-vegetarian women aged 65–90 years. In conclusion, for women aged 40–55 years, vegetarian diets reduced bone quantity, as measured by BMD, but not bone quality, as measured by TBS.

Background: Optimal nutritional care is essential to improving outcomes in hemodialysis, yet translation of evidence into routine practice remains uneven across settings. To inform health system planning and implementation priorities, we mapped global research on hemodialysis-related nutrition. Methods: We searched the Web of Science Core Collection for English-language original articles on nutrition and hemodialysis from 1 January 2006 to 13 October 2025. Publication trends, productivity by country and institution, influential journals and authors, citation impact, and conceptual structure via Keyword Plus co-occurrence, trend, and thematic evolution analyses were assessed using the bibliometrix package (version 5.0) in R. Results: A total of 332 articles from 115 journals were identified, with substantial growth and multidisciplinary authorship, though international collaboration remains limited. The United States contributed 21.4% of publications and achieved the highest citation impact, while China, Japan, Iran, and Brazil formed the next tier of contributors. The Journal of Renal Nutrition accounted for 16.6% of papers. Highly cited studies established links between dietary intake, mineral and electrolyte management, and survival, while supporting the use of intradialytic oral nutritional supplements. Thematic evolution showed a shift from biochemical markers toward patient-centered priorities, including diet quality, adherence, body composition, mental health, and quality of life. Emerging directions point to whole-diet approaches and microbiome-modulating strategies. Conclusions: Global research on diet and hemodialysis has progressed from foundational nutrient studies to multidimensional, patient-focused approaches. Our findings suggest opportunities for health systems to strengthen dietitian-led models of care, integrate patient-reported outcomes, and prioritize scalable nutrition interventions within routine dialysis services.