The `Marry the Night` singer - who has previously professed a love of drinking whiskey - had decided to consume less alcohol as she is no longer "depressed" thanks to her boyfriend Taylor Kinney.
A source said: "Gaga had an intimate chat with fans backstage on the `Born This Way Ball` tour in Amsterdam.
"She told them, `I`ve toned down my drinking because I`m not depressed like before. Now I only have one glass of wine every now and then."
It is not only her drinking habits that the singer has changed.
Gaga recently went on a new diet when she reached the European leg of her world tour, in the hope she would drop 10lb in just four weeks.
A source said: "Gaga has decided to go on a major body blitz and cut out all gluten and wheat from her diet, which is very hard to do. She has given her people strict instruction to advise staff at venues and restaurants about her new diet because she is taking it very seriously.