Low-Fat Yogurt Consumption Modulates Insulin in Obese Mice

Abstract

Abstract Objectives The objective of this study was to determine how low-fat yogurt consumption affects obese mice fed on standardized western diet. Methods C57BL6 mice were acclimatized for 2 weeks prior to experiments. Mice were fed either a chow diet (C, Teklad global 2014C) or a standard high-fat diet (F, TD.06414, 60.3% kcal from fat) for 11 weeks to induce increased fat mass and obesity. Then, the mice were further randomized to receive either a typical western diet (FC and CC, TD.07201) or a yogurt-supplemented diets (FY and CY, 5.6% lyophilized yogurt) for 3 weeks to test how yogurt consumption inhibits markers of obesity. Body weight and food intake were recorded weekly. Adipose tissues and liver weights were also measured. Fasting plasma (for 4 hours) was collected to determine glucose and insulin level. Results After 11 weeks, the mean body weights of mice fed with C and F diets were 27.0 ± 0.7 and 37.4 ± 1.6 g, respectively (P < 0.05). Consumption of the western diet rapidly induced weight gain in the chow-fed mice over the subsequent 3 weeks relative to obese mice due to increased food intake. Thus, at week 14, the groups had similar mean body weights ranging from 32.6 to 41.5 g. In mice initially fed with chow diet, yogurt intake reduced food consumption to levels intermediate to the CC and FY/CY groups. For the liver weight, no significant difference was found between FC and FY group. Retroperitoneal adipose tissue was increased by 62% in FC group compared to CC group (P < 0.001), and yogurt did not affect tissue weights in either group. Fasting glucose levels were not significantly different between FC and FY. FC had increased fasting insulin at 2.49 ± 1.99 µg/L compared to CC (P < 0.01), and was normalized by yogurt supplementation to 1.44 ± 1.14 µg/L in FY (P < 0.05). Likewise, the HOMA-IR index was significantly increased in FC compared to CY (P < 0.05), but not in FY. Conclusions Yogurt did not prevent the rapid weight gain in mice induced by a Western diet. In obese mice, yogurt effectively inhibited fasting hyperinsulemia as part of a Western diet. Funding Sources Supported by National Dairy Council.