What d'you think of the treat?
The same article notes that it's very hard to get all the vitamin D you need from food.
However, many foods are fortified with vitamin D, so while fortified foods can't provide all the vitamin D you need, it's still helpful.
While there are many different schools of thought on how much D you need to maintain optimal health, doctors recommend that you get anywhere from 1,000 to 2,000 international units (IU) of vitamin D a day.