So when it comes to gaining weight, it all comes down to more calories in than out. If you add some gainer shakes along with your normal meals, you're sure to see some progress! There are nutritional shakes like Boost, but these can cost quite a bit especially if you're wanting to buy in bulk. It's cheaper to get ingredients to make your own shakes, such as using fruit, chocolate syrup, whole milk, etc. Even buying big containers of mass gainer can help you gain weight too. So to those who are gaining weight, are you using shakes along with your meals? I have been doing this and it's been helping.