This is such a common question and we get asked it a lot. We’ll start at the beginning:
Protein is made from amino acids, which are the building blocks of our body. They make our cells, our hair, our skin, our nails. We get protein from our diets and its one of the three macronutrients we need to survive. So no, protein doesn’t make you fat. It is a vital component of what makes your body work. However, when protein (in whatever form it takes in your diet: chicken or other meat, beans, grains etc) is deep-fried or covered in calorific sauces or eaten in excess, then it’s going to add to your calorie intake and lead to weight gain.
However, in the context of this question, what’s really being asked, is if protein powder makes you fat. The same applies as above. On its own and as part of a balanced diet, protein powder doesn’t make you fat. Many use it as a more convenient way to add protein to their diet to build muscle, but this should be as part of a sensible diet and gym routine.
It’s pretty simple: you will gain weight if you are consuming more calories than your body needs and running your system at a calorie surplus. Single food items won’t make you fat – it’s a cumulative process that, when combined with lack of activity, will affect your general health and weight.