Doctors are calling for the 'sunshine vitamin' to be cheaper to help kids stay healthy.
We get vitamin D from sunlight and it helps to keep our bones and teeth healthy but doctors are worried one in four children in Britain isn't getting enough.
A lack of the vitamin can lead to a range of diseases like diabetes and rickets where bones don't develop properly.
Some doctors want vitamin tablets to be more easily available and cheaper, the government says it already gives them out free to those most in need.
Although it it important to keep safe in strong sunshine by using sunscreen and covering up, the body does need us to get sunlight to help it make important vitamins like vitamin D.
People who have darker skin are less likely to get sunburnt but they need more sunlight to make vitamin D than people with lighter skin.
People who have to stay indoors or need to keep themselves covered up when they go outside might need to take vitamin D as a supplement to keep them healthy.
Vitamin D comes mainly from being out in the sun but is in some foods as well.
•oily fish, such as salmon and sardines
•fortified fat spreads
•fortified breakfast cereals