I was shocked to learn that many children today are deficient in vitamin D. Apparently, using sunscreen to prevent skin cancer also prevents our kids from absorbing the helpful vitamin D from the sun. Our pediatrician recommended the Carlson brand and so we bought a bottle. The dosage is really small, only one drop, and you can mix it into a drink. However, my kids insisted that the drop made their entire glass of milk taste bad and instead chose to have it dripped into their mouths. I had a heck of a time remembering to give them their supplement on a regular basis. I would try to give the drops in the morning, but in the busyness of breakfast and signing permission slips signed and cleaning up milk spills, I forgot all the time. Also the drops come out slowly, then quickly which can make them hard to dose. They taste really oily, which is a bummer. On the plus side, one drop gives you the entire amount of IUs on the bottle. Many other brands will be labeled as 1000 or 2000 IUs, but only have 400 per drop. Our family switched to pills, which can be put in a pillbox and are easier t9 remember.