"protein powder" that i mentioned is "muscle gainer". it's how you use it. having a healthy diet may be enough to be fit, but if you want to build your body higher you'll need to use things like "muscle gainer".
Depends on what you're aiming for. If you're a olympic weightlifter, of course you'll gonna need some gainer. If you're just trying to get in good shape, you don't. That gainer is nothing more than concentrated proteins, which you could get much cheaper by just eating a big omelette.
as someone who struggled getting to a stable ~4500cal a day, i can totally see why people use them. it's not so much about having a healthy diet as it is about going like 10% above your maintenance level of calories. i had an extremely healthy diet, but i didn't have the volume i needed to hit that target.
protein powder isn't even expensive, it's the "mass gainer" stuff you want to stay clear of, because it's far cheaper to make your own
Of course, if you are eating 4500cal a day, you'll probably need protein powder. But then again, those kind of numbers are far from normal, and I'm tempted to categorize that under "olympic weightlifter" (see above).
Even protein powder is expensive over here :/ But I was refering to the stuff the sell over here which contains proteins, vitamins and minerals. I guess it's the equivalent of what you call "mass gainer".