I am on my doctor's orders to have 2500IU daily due to extreme Vitamin D deficiency. When I found this liquid option with the same units I needed to take.... I was thrilled. I hate taking multiple pills....so now I just take one pump per day on my tongue and the taste is great - refreshing citrus flavor. I just had my labs rechecked and my Vitamin D is in the normal range after one month of taking this product. -KM