Promotes natural immunity Supports bone health Contains 400 IU of vitamin D3 per serving Free of gluten, dairy, soy, sugar, salt, nuts, and artificial colors of flavors Sunlight is our primary source of vitamin D—an essential vitamin that promotes bone health and immune function by regulating calcium absorption and phosphorus levels. But between cloudy skies, office jobs, school, and relaxing days spent indoors, getting your recommended 600 IU of vitamin D per day can be tough. A single The Vitamin Shoppe ® brand Vitamin D3 softgel features 400 IU of vitamin D3 so your body has what it needs to support strong bones and a healthy immune system.