Hilchos Lashon Hara chapter 9, section 3

One must be careful not to give praise that leads to loss. For example, to publicize that someone provided him with eat and drink and went to a lot of trouble for him, for through this many empty people will go to him and deplete his money. Regarding this it says, If who blesses his fellow with a loud voice early in the morning – it is regarded as a curse for him (Proverbs 27:14). From this we learn that if one got a loan, he should not publicize the lender’s generosity. It is also dust of lashon hara to say things that make people suspect he is speaking lashon hara.