Can you use PLA material with food and drinks? I would like to print fancy plastic cutlery sets or plastic glasses.

Is it safe to do it? Or bad for your health, if so, why?
As others have pointed out, PLA isn't specifically not food safe, but materials that have been printed previously can contaminate the PLA.

Additionally, anything 3D printed is extremely porous. Once a part is used for food, moisture and bacteria will accumulate in the pores, and can never be completely cleaned out, contaminating any food that contacts it. It can't be sterilized either, because the temperatures needed for sterilization would deform or melt the plastic.