I have started intermittent fasting and working out.I want to gain muscle and lose fat.So I have decided to take whey protein for the first time, but I'm confused when can I take it as my 16 hours window consists of work out and not eating anything. But I have a doubt like will I gain weight by taking whey?
Let's get something straight. To gain muslce, or gain weight for that matter, you don't need to consume any supplements.
The best protein you can consume is from real food. That being said, it can be hard to consume enough protein from just food. This is the reason many people supplement this in with shakes.
Whether you will gain muscles or not will depend on the amount of calories you consume and the amount of calories you burn. If your caloric intake it too low, you're most likely going to lose weight. If you recently started working out, it's very possible to gain muscle while also losing weight but the longer you work out, the harder it will become to combine the two.
TLDR: You won't magically gain weight from taking a protein supplement, but it can help to consum enough protein during the day to feed your muscles so that they can grow. My advice would be to consume the shake directly after a workout together with a meal that consist of the necessary macronutrients.
Through taking protein alone is not enough to gain weight (if that's your goal) when you work out your body needs energy and burns calories. You need to make sure that you eat a lot of calories in the window that you have to keep up your muscle and make sure you have enough energy. Whey protein is obviously going to help you get the protein intake that you require especially in your specific conditions
On the other hand if you're trying to lose weight then taking whey in your windows to intake can be a good supplement to help increasing your metabolic rate also.