Is it allowed to write an article/ebook about someone else's work?

I want to write a super in-depth blog post (or write an ebook) on an existing study on nutrition, since I discovered a great keyword opportunity. My question though is - Is that legal?

In the blog post of book I will obviously not claim that I'm the inventor of the concept or the researcher who did the study. I will just explain the background, how to use the findings, recipes etc. and also talk about my own experience with it. In several paragraphs, I will also mention the researcher and his background, and even mention one of his books. Plus at the end I will list the resources I used.

Does anyone know if this is ok and legal or am I setting myself up for trouble?

Thx