Protecting a mattress

Hi, my question is a little off topic but related to mattresses. I understand if you can't or won't answer. I occasionally suffer from very bad night sweats. What would you recommend to protect my mattress? We currently have standard cotton bedding and a while fibre topper, but it soaks through to the mattress, which can't be good for it. Would you recommend something like Coolmax? There's also an American brand called Wicked which try to fix this, but they aren't cheap. Again, apologies if this isn't your expertise. Many thanks.