## 4 Discussion
This disparity may be attributed to various factors, including dietary habits, food fortification practices, and vitamin D supplement usage in different regions. Intervention programs typically evaluate the effectiveness of calcium and/or vitamin D supplementation on bone metabolism by assessing changes in whole-body bone mineral density (BMD), rather than specific bone health indicators [47]. During the present study, significant increases in whole-body BMD were observed in all four study groups, with the highest increase noted in group III, followed by group IV, I, and II, in descending order. Similar findings have been reported in previous research, particularly in postmenopausal Caucasian women receiving calcium supplementation (1600 mg/d) for a year [48]. While dietary interventions aim to mitigate age-related declines in BMD, significant increases are not typically expected. Some nutritional interventions have shown no effect on whole-body BMD [49], while others have reported moderate declines in bone loss following calcium and vitamin D supplementation [50]. The highest increase in whole-body BMD observed in group I may be attributed to vitamin C supplementation, as vitamin C plays a significant role in bone health. Research indicates that dietary vitamin C intake is associated with higher whole-body BMD in postmenopausal women [51] and affects bone turnover by enhancing collagen synthesis and osteoblast genesis [52]. Additionally, studies have shown an inverse relationship between vitamin C intake and the risk of fracture or osteoporosis [53]. Experimental pre-clinical data also suggest that a polyphenol-rich olive extract may help maintain whole-body bone mineral density (BMD) in postmenopausal women at high risk of osteoporosis [54]. Continuous monitoring of diet and supplementation is crucial for assessing long-term impacts on BMD response, and larger sample sizes are needed for comprehensive evaluation. Previous studies [55; 56; 57] have linked serum parameters like triglycerides (TG) and cholesterol with bone health and metabolism. In our study, normal TG levels (<150 mg/dL) were seen in groups I, II, and IV, while group III showed borderline high levels (150-199 mg/dL) both at baseline and study end. Total cholesterol remained within normal ranges (<200 mg/dL) for groups II, III, IV, with the group showing borderline high levels (200-239 mg/dL). LDL (100-129 mg/dL) and HDL (>60 mg/dL) levels were normal in all groups at both time points. These findings are consistent with prior research on calcium and vitamin D co-supplementation, indicating no association with serum LDL levels [50]. Additionally, group IV showed significant improvements in total cholesterol, and group I exhibited positive changes in HDL, aligning with previous studies suggesting a beneficial effect of vitamin D and calcium supplementation on these parameters. The variability in the above results underscores the necessity for larger-scale, well-designed intervention trials to elucidate the effects of micronutrient supplementation on lipid biomarkers. Nonetheless, the significant reduction in total cholesterol observed in group IV, coupled with the statistical increase in BMD, indicates a positive impact. This aligns with previous research suggesting a negative correlation between total cholesterol and BMD [55; 56]. Consistent with our findings, [PERSON] et al. documented physiological ranges in serum lipid profiles for total cholesterol, TG, LDL, and HDL-cholesterol after administering a combination of polyphenol-rich olive extract (250 mg/day) and calcium (1000 mg/day) [57]. Both our study and that of [PERSON] et al. suggest a novel positive influence on blood lipid profiles, potentially offering additional health benefits associated with olive polyphenol intake. However, conclusive statements regarding the effect of micronutrient supplementation on lipid profile biomarkers in postmenopausal women cannot be drawn from our study alone, necessitating further investigation.