Higher calcium and/or vitamin D intake may be associated with lower body weight and better metabolic health. A group of clinical nutrition researchers out of China studied the effects of calcium plus vitamin D3 supplementation in healthy overweight and obese adults whose calcium consumptions were considered very low. The researcher measured bodyweight, BMI, body composition, waist circumference, blood pressure and metabolic profiles during a 12-week energy-restricted diet (i.e., 500 calories below maintenance level). Compared to a calorie-restricted diet alone, adults who supplemented with 600 mg elemental calcium and 125 IU vitamin D3 per day experienced significantly greater decreases in fat mass loss and visceral fat mass/visceral fat area loss. If you are restricting your calorie intake and may be under-consuming calcium, add calcium plus vitamin D3 into your supplementation regimen for at least 12 weeks to augment body fat and visceral fat loss.
[Zhu, Wei, et al. “Calcium plus vitamin D3 supplementation facilitated fat loss in overweight and obese college students with very-low calcium consumption: a randomized controlled trial.” Nutr J 12.1 (2013): 8.]