Yes indeed. A lot of commercial GF food is, if anything, higher in fat and sugar than the "regular" gluten-containing equivalent. Just because a product is "free from" something-or-other (whether gluten, lactose, nuts, whatever) doesn't mean it's healthy.

We've gone GF at our house because my wife has coeliac disease. But we use very few commercially-prepared GF products; we cook at home from basic ingredients, and simply avoid the gluten-containing grains.

If you basically went gluten free by relying on products from the supermarket "free from" section, I can imagine it's easy to gain rather than lose weight.

Not going to say it works for everybody. I was having a lot of GI issues and was diagnosed with IBS. Decided to try GF before committing to taking medicine 4 times a day, indefinitely...and it just happened to work.

The weight loss was an unexpected side effect.

You can drop the "if". Almost everything sold by a supermarket is junk food. Avoiding junk food at the supermarket is almost impossible.