Dr. Pickart, can mineral sunscreens with high pH's damage the skin overtime? I know that my mineral sunscreen's pH is 8.0, because it producers say that otherwise the zinc oxide in the formula will not be stable and will release ions.

Is there a way to not let the alkalinity of this sunscreen's pH affect my skin, such as creating a barrier on the skin before applying it?

I heard that emu oil, or squalane, or even mineral oil, or something with dimethicone might be good, but not sure if this would solve this problem? I really don't want my sunscreen to raise my skin's pH because I heard it's not good for the skin in the long run.

A pH of 8.0 is not really a good idea.

I don't care for mineral oil or dimethicone since they are very alien to the human body.

Look at http://cincovidas.com/dimethic...osmetics-ingredient/

Why Dimethicone is Bad for Your Skin

That artificial coating on the outside of skin causes several issues:

It traps everything under it—including bacteria, sebum, and impurities—which could lead to increased breakouts and blackheads
The coating action actually prevents the skin from performing its normal activities—like sweating, temperature regulating, sloughing off dead skin cells, etc.
Prolonged exposure to dimethicone can actually increase skin irritation, due to the coating property and because dimethicone is listed as a possible skin and eye irritant
Those with sensitive or reactive skin are at risk of an allergic reaction to dimethicone
On top of all this, dimethicone is a non-biodegradable chemical—bad for the environment

The website has more information on this.