Pick brands named with the NSF Worldwide, US Pharmacopeia, Guarantors Lab, or Customer Lab seal. These confirm that the item really contains the fixings that the name says it does, and that the item has no possibly destructive fixings
In humans, vitamin c.
It is a compound, so it is a pure substance.
Yes because it is 1 compound: C4H5N3O. It does have to mix with other compounds to be created.
No calcium is in pure vitamin C. It is possible a manufacture may prepare the calcium salt of vitamin C in its formulation. The label would indicate that.
It is a compound, so it is a pure substance.
Vitamin D, Vitamin B, Vitamin E Good for me, makes you pee Anything with the "ee" sound really.
Not exactly. The body will convert Beta Carotene into Vitamin A when it is needed. That's why Beta Carotene is the preferred and safer version of Vitamin A... you can overdose on pure Vitamin A easier than you can on Beta Carotene
B
skin
No, collagen is a type of protein and retinol is a pure form of Vitamin A.
Vitamin E is an anti-oxidant which is very soothing if applied to a burn. (But can be sticky and difficult to apply to the skin in its pure form)
If there is no salt or substance that makes it impure it is a pure mixture