You have quite a few questions and they're all tangled up together. 1) are there side effects to taking protein supplements or mass gainers? Practically, no.

You have quite a few questions and they're all tangled up together. 1) are there side effects to taking protein supplements or mass gainers? Practically, no. Whey protein, which is the most common protein supplement taken around working out, is just concentrated food. It's widely tested and incredibly safe. A small number of people (including myself) get a lot of mucus at the back of their throat when they start taking whey protein, but that's just a rare reaction to large amounts of dairy. The safety of every supplement would, of course, also depend on the purity and therefore on the manufacturer so do your due diligence before you buy. But in general people who warn you against using common supplements such as protein/creatine/bcaa have done no research and are simply having an adverse reaction to seeing a powder or a pill. 2) is it a good idea to take protein supplements or mass gainers? - mass gainers - pretty much never a good idea. They're just protein + carbs. Usually with too much carbs and at inflated prices for the concentrations that you're getting. If for some reason you've decided that you need a protein + carb supplement, you can get them separately and mix your own shake at the ratio that you want. - protein - maybe. It certainly won't hurt but you would probably expect to see changes in your body that simply won't happen. If you've worked out for a year and not seen any progress, it's likely that your training and/or diet haven't been that good. So adding a protein supplement won't do much. 3) So to give a general outline to solving your problem: - make sure that you're training heavy (relative to your ability). Use mainly compound lifts (squat, deadlift, military press, bench press, pull-up) and get on a program that would allow you to progressively get stronger and lift more. - eat more. This is the biggest factor in gaining weight. Calorie counting has many problems and usually isn't necessary. But you can start with recording everything you eat for a period of a couple of days to a week. And then increase your intake without adding too much junk or sugar. Make sure you're getting enough protein in your diet in the form of meat/eggs. If this doesn't work, you're probably still not eating enough. - make sure that you're getting 7.5 - 8.5 hours of uninterrupted sleep every night - don't worry about supplements until you start seeing progress from training and diet. And don't expect to see significant results just from adding a supplement.