How many books do you guys read at a time?

I'm currently in a debacle. I'm reading two non-fiction books at the moment and don't know if I should add 3 more books to my roster. They all deal in either weight loss or self help. So they're all semi related. I don't know if it is a wise decision or if I will comprehend less if I read more books at once. What is the consensus on this? Will I be good if I read 5 books, or should I stick to two?



Oh an fyi, I've read two of the books all the way through before and I'm rereading them. I don't know if this changes anything.

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