Cotton pillowcases create unnecessary friction, leading to frizz and breakage...

https://www.bookmarks4all.win/waking-up-with-bedhead-cotton-pillowcases-cause-friction-that-leads-to

Cotton pillowcases create unnecessary friction, leading to frizz and breakage while you sleep. Swapping to silk allows hair to glide, reducing damage. For extra protection, secure your hair in a loose braid or scrunchie