Clinical Strength. Healthy Origins Vitamin D3 10000 IU is a key nutrient manufactured in a highly absorbable liquid softgel form. Vitamin D3 is synthesized in the body form sunlight and only a small amount can be obtained from food.  . The winter season and most all sun block products inhibit the body's ability to produce optimal levels of Vitamin D. As a result Vitamin D3 supplementation becomes even more necessary to ensure your body receives an adequate supply.