Can I Substitute white wine for red wine?

The rule of thumb never applies, it all depends on pairing of foods. AKA will you be having tapas or appetizers before hand. You know your own body, and you decide which wines will pair with certain foods, and another point to look at, just because you start with white then move to red, you may forget that port wine, or dessert wine you may have at the end may be a red or a white! Great question!

You always want to serve the lightest wine first. White first, then Red Wine.

I don't know if there is scientific proof for this, but some swear by this rule ( I am one of them)

It can make your stomach unsettled at times if not followed.