Sources have said that the singer hopes that she will increase her energy levels and lose weight for the last leg of her tour.
Giving up rice, the singer is mainly sticking to a diet of fish, chicken and vegetables - but let's herself snack on a few gluten-free cookies.
The source told Sky News: "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."
The already skinny star is not the first celeb to ditch gluten.
Miley Cyrus hit headlines this year for attributing her big weight loss to a mix of gluten-free eating and a rigorous Pilates regime.
Gluten-free diets, not to be confused with carb-free, are controversial as there is no scientific evidence to prove that it aids weight loss.
However, naturally gluten-free foods such as fruit and vegetables, lean protein and nuts are all linked to a healthy diet good for weight loss.
We don't think you need to lose a pound Gaga!
Lady Gaga's hair is now 'Louis Vuitton brown'
50 ways to burn 100 calories
Get toned legs like Lea Michele in time for hot pant season
5 free fitness apps you need in your life