To be honest, SPF in makeup is pointless, and potentially dangerous.
To explain, it's pointless because for sun protection to actually work you have to apply a specific amount and makeup doesn't actually bother telling you how much that amount is. The thing is, if you don't apply said specific amount it's not like applying 50% will give you 50% of the protection, anything less and you'll have stuff all protection. Even if you happen to apply enough, the reality is that sun protection needs to be reapplied regularly even if you're not running about sweating it off or swimming, and by regularly I mean every two hours, you can't simply slap it on at the beginning of the day and expect it to last SPF simply does not work that way. So, in reality, that minimal amount of protection in most makeup is completely meaningless. As for the dangerous bit, the reason I say this is because SPF in makeup is very misleading, due to what I've already said. But, because of this, it can lead people to think they are protected when they aren't. SPF in makeup is nothing more than marketing, don't be fooled.
As for your comment about LA not having SPF. SPF isn't an ingredient, it's a rating system. Just because a product doesn't have a rating doesn't mean that it doesn't offer some form of SPF, it simply means the company in question didn't pay an arm and a leg to get the product put through official testing. A product, in most civilized countries, can not legally display an SPF rating without those tests to back them up. And, in places like America companies aren't legally allowed to even say or imply that a product offers sun protection in a general sense without having those tests to back such a statement.
I haven't tried LA Minerals, and I've never tried Bare Escentuals as I've read too many reviews on people who had reactions to their formula/ingredients. Personally, I like indie brands. There's a lot out there, they're cheaper, every bit as good and many rate them more highly.
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