# Physiological Effects of Hydrolyzed Skim Milk and Probiotics on Osteoporosis Models
## 3 Results and Discussion
### Attenuation of the OVX-Driven Effects of Skim Milk and Probiotics  
Micro-CT imaging of the distal metaphysis of femurs was performed to analyze the effects of skim milk and probiotics on OVX-induced osteoporosis models. The number of reconstructed femurs decreased in the OVX group and was restored by the consumption of skim milk and probiotics (Figure 2A). Compared to the control group, the percentages of BV/TV, Tb.Th, and Tb.N significantly decreased (Figure 2B-D), while that of Tb.Sp significantly increased in the OVX group (Figure 2E). For the OVX groups administered skim milk and skim milk with probiotics, the levels of BV/TV, Tb.Th, and Tb.N were significantly increased by the consumption of skim milk and skim milk with probiotics (Figure 2B-D). The percentage of Tb.Sp significantly decreased when skim milk was consumed alone or in combination with probiotics (Figure 2E). Milk and dairy products contain proteins, minerals, and vitamins that are beneficial for bone health [25]. Skim or nonfat milk is  
Figure 1: Changes in body weights and serum lipid profiles due to ovariectomy (OVX) and skim-milk and probiotic treatment. Changes in body weight from weeks 0 to 8 (**A**). Concentrations of calcium (**B**), triglycerides (**C**), and low-density lipoprotein cholesterol (LDL-C) in the serum of each experiment group (**D**). Data from the experimental group were compared with data from the OVX group. Data are presented as mean \(\pm\) SD (\(n\) = 5). The values of \({}^{*}\)\(p\) < 0.05 and \({}^{**}\)\(p\) < 0.01 were considered to indicate statistical significance. milk in which the milk fat has been removed. As a result, this milk has fewer calories and a higher percentage of calcium by weight. According to a prior study, the calcium concentration in skim milk is 244 mg/200 mL, which is higher than that in whole milk (236 mg/200 mL) [12]. Skim milk contains higher amounts of vitamins than whole milk owing to fortification. In recent years, several studies have reported the potential benefits of probiotic supplementation on bone health under both healthy and pathological conditions. _L. casei_ and _L. acidophilus_, either alone or in combination, decreased bone damage and effectively restored the antioxidant status of the liver and kidneys [26]. _L. reuteri_ treatment significantly protects OVX mice from bone loss. The levels of osteoclast bone resorption markers and activators (Trap5 and RANKL) and osteoclastogenesis were significantly downregulated in _L. reuteri_-treated mice [27]. In this study, we used the probiotic combination of _Lactobacillus_, _L. delbrueckii_ ssp. _bulgaricus L. Lactis_, _Bif. animalis_ ssp. _lactis_, and _Streptococcus thermophiles_, which are abundant in zygurt starter cultures. Based on the results, the consumption of skim milk with probiotics was similar to zygurt consumption, and skim milk had a positive effect on bone density when supplemented with probiotics. Fermented milk consists of zygurt, cultured cream, and buttermilk. However, various processes and equipment are required for milk fermentation. Here, we suggest that a mixture of skim milk and probiotics without fermentation is effective at reducing weight gain and preventing osteoporosis in elderly individuals. This mixture is also economical because it excludes the fermentation process, despite evidence that various products, such as acids, produced through the fermentation process, positively affect human health [28]. Figure 2: Effects of ovariectomy (OVX) and the consumption of skim milk and probiotics on bone mineral density and bone mineral content. (**A**) Longitudinal and transverse cross-sections of representative micro-CT reconstructed femurs after a four-week treatment with skim milk and probiotics. Skim-milk- and probiotic-driven suppression of OVX-induced loss of femoral bone volume/tissue volume ratio (BV/TV) (**B**), trabecular number (Tb.N) (**C**), trabecular thickness (Tb.Th) (**D**), and trabecular spacing (Tb.Sp) (**E**). The results are presented as mean \(\pm\) SD.