Why are you doing this? It isn't very pleasant. Suppose you do it without the user's knowledge. Personally, I, as well as many others, hate this kind of mailing list. I especially don't like advice like "Are you tired of everything? Is life going downhill? Sit in a chair, relax, and order knives." God, it sounds like a set of idiotic knives will actually help you find happiness. I hate all these newsletters so much that i use
uk temp number when I sign up for sites that require SMS verification, so I don't get these newsletters. In general, you should not do this—respect people's privacy. Do not pry into it.