Doesn’t this kind of thing strip your enamel?
Nope, it shouldn't.
Look:
Tooth enamel is one of the four major tissues that make up the
tooth in humans and many other animals, including some species of fish. It makes up the normally visible part of the tooth, covering the
crown. The other major tissues are
dentin,
cementum, and
dental pulp. It is a very hard, white to off-white, highly mineralised substance that acts as a barrier to protect the tooth but can become susceptible to degradation, especially by acids from food and drink.
Enamel is the hardest substance in the human body and contains the highest percentage of minerals,
[1] 96%, with water and organic material composing the rest.
[2] The primary mineral is
hydroxyapatite, which is a
crystalline calcium phosphate.
[3] Enamel is formed on the tooth while the tooth is developing within the gum, before it
erupts into the mouth. Once fully formed, it does not contain blood vessels or nerves.
Remineralisation of teeth can repair damage to the tooth to a certain degree but damage beyond that cannot be repaired by the body. The maintenance and repair of human tooth enamel is one of the primary concerns of
dentistry.
In humans, enamel varies in thickness over the surface of the tooth, often thickest at the
cusp, up to 2.5 mm, and thinnest at its border with the
cementum at the
cementoenamel junction (CEJ).
[4]
https://en.wikipedia.org/wiki/Tooth_enamel
Don't forget that most whitening toothpastes just remove staining.
The whiteness of your teeth highly depends on your tooth enamel and apart from getting your dentist to fix it, there is little you can do.
Also, teeth aren't meant to be 'Hollywood' white. Teeth are meant to be a little bit yellow.
What we actually do, is to try to remove all stains caused of drinks, food, in some people's cases smoking.
What I understand, is that the tooth enamel has to be white in its natural condition.