It's a human study, of course, and although they found the link, they couldn't determine if poor sleep is caused by poor nutrition or if poor nutrition is caused by poor sleep but, if you ask me, it's poor nutrition causes poor sleep because they did find that when the people with poor sleep took supplements, they got better sleep.
https://www.slashgear.com/study-links-p ... -09579778/
https://medicalxpress.com/news/2019-06- ... ition.html