[@PrarieD0G]

@PrarieD0G asked the Naked Scientists:
   
Do you recommend taking a daily fish oil supplement or multivitamin? Are they actually effective?

What do you think?

[CliffordK]

If you have a well balanced diet. 
Fruits, Vegetables, Meats, Dairy, etc...  every day.
Then you may not need vitamins.

If your diet is unbalanced for whatever reason, then it might not be a bad idea.

Folic Acid has been shown to reduce certain types of birth defects when taken in early pregnancy (or prior to becoming pregnant).
If you have a history of osteoporosis in your family, then Calcium, Vitamin D, and perhaps Magnesium might be appropriate, even starting quite young.

Many other vitamin supplements are very controversial about the actual magnitude of their effects.