Poly-Vi-Sol with Iron - is there a better way for my son to get vitamin d other than taking poly vi?

from http://www.drugs.com/enc/vitamin-d.html

Vitamin D

Definition
Vitamin D is a fat-soluble vitamin that helps the body absorb calcium. Fat-soluble vitamins are stored in the body's fatty tissue.

Function
In addition to helping the body absorb calcium, vitamin D also helps the body keep the right amount of calcium and phosphorus in the blood.

Food Sources
Vitamin D is found in the following foods:
* Dairy products
o Cheese
o Butter
o Cream
o Fortified milk (all milk in the U.S. is fortified with vitamin D)
* Fish
* Oysters
* Fortified cereals
* Margarine

Recommendations

The best way to get the daily requirement of essential vitamins is to eat a balanced diet that contains a variety of foods from the food guide pyramid.

Vitamin D is also known as the "sunshine vitamin" because the body manufactures the vitamin after being exposed to sunshine. Ten to 15 minutes of sunshine 3 times weekly is enough to produce the body's requirement of vitamin D.

Specific recommendations for each vitamin depend on age, gender, and other factors (such as pregnancy). In general, those over age 50 need slightly higher amounts of vitamin D than younger persons.