Comparison of the effect of daily consumption of probiotic compared with low-fat conventional yogurt on weight loss in healthy obese women following an energy-restricted diet: a randomized controlled trial1

Background: Despite evidence for the beneficial effects of probiotics and low-fat dairy products, to our knowledge, no study has compared the beneficial effect on weight loss of consuming a probiotic yogurt (PY) compared with a standard low-fat yogurt (LF) during a hypoenergetic program. Objective: We compared the effect of the PY with LF yogurt consumption on body weight and cardiometabolic risk factors in women during a weight-loss program. Design: Overweight and obese women [body mass index (in kg/m): 27–40; age: 18–50 y) who usually consumed standard LFs were asked to consume either PY or LF every day with their main meals for 12 wk while following a weight-loss program. Results: A total of 89 participants were randomly assigned to one of the 2 intervention groups. Baseline variables were not significantly different between groups. A statistically significant reduction in anthropometric measurements and significant improvements in cardiometabolic risk characteristics were observed over the 12 wk in both groups. However, no significant differences in weight loss and anthropometric measurements were seen between groups after the intervention. Compared with the LF group, the PY group had a greater (mean6 SD) decrease in total cholesterol (PY =20.366 0.10 mmol/L, LF = 20.31 6 0.10 mmol/L; P = 0.024), low-density lipoprotein cholesterol (PY = 20.35 6 0.10 mmol/L, LF = 20.31 6 0.11 mmol/L; P = 0.018), homeostasis model assessment of insulin resistance (PY = 20.55 6 0.32, LF = 20.42 6 0.20; P = 0.002), 2-h postprandial glucose (PY = 20.61 6 0.24 mmol/L, LF = –0.44 6 0.19 mmol/L; P , 0.001), and fasting insulin concentration (PY = 21.76 6 1.01 mU/mL, LF = 21.32 6 0.62 mU/mL; P = 0.002), as secondary endpoints after the study. No significant differences were found for fasting plasma glucose, high-density lipoprotein cholesterol, or triglycerides within both groups after the 12 wk. Conclusion: Consumption of PY compared with LF with main meals showed no significant effects on weight loss. However, it may have positive effects on lipid profiles and insulin sensitivity during a weight-loss program. This trial was registered at http:// www.irct.ir/ as IRCT201402177754N8. Am J Clin Nutr