Is it ok to give fat free yoghurt and skimmed milk to a 4yo?

[DingDongDraculaOnHigh]

dd doesnt seem to notice the difference so surely is best? She tends towards slight podginess despite eating very healthily (like me grrrr) so I can't help but think it would be good.

Is there any reason why not?

full fat until over 2 then semi till over 5 then they can have skimmed if need be.(i read this in a child nutrition book) You can stick with full fat if you want to, it is a personnel choice i suppose.
Dont know about yogurt i always use full fat natural yeo valley as its so yummy!!