“May be” is the point.

From the Forbes article you cite:

“KEY QUOTE

‘It’s important to emphasize that these findings are observational, and they provide insights into patterns within our dataset. However, they do not establish a direct cause-and-effect relationship,’ lead author Dr. Anees Bahji, at the University of Calgary’s Cumming School of Medicine, told Forbes.”

Drinking anything other than water, breathing anything other than air, and eating just about anything have been shown in some study somewhere to be harmful in someway.