Q: "If I want to gain muscle, I need to eat more protein right?"
A: Not necessarily.
If you are training & wanting to gain muscle, protein should make up 10-35% of your total calorie intake for the day, according to the American College of Sports Medicine (ACSM).
The Australia Institute of Sport (ASI) and ACSM say that the current scientific evidence shows little to no additional sport benefit of consuming a high-protein diet (>2g/kg/day), and that doing so can actually do more harm than good -- excess calories from protein can be converted to fat & the extra protein can put stress on the kidneys (as they have to deal with the extra waste from the breakdown of the protein).
"Strength athlete’s muscles seem to adapt to the stress of resistance exercise, so that the protein requirements to maintain protein balance in very well-trained athletes are only marginally greater than those of generally active people (1.0-1.2 g of protein/kg/day)." - AIS
For the general population doing strength training the recommended 2-3 times per week, the Australia Dietary Guidelines still recommend 0.8 g of protein/kg/day. What this 10-35% of total calories range looks like for a 68kg adult-male: ~60 grams of protein PER DAY
In food terms that is:
3 servings low-fat dairy (1 serving = 1 cup yoghurt OR 40g hard cheese OR 1 cup milk)
+ 3 servings lean protein (1 serving = 65g beef, lamb, pork OR 80g chicken OR 100g fish OR 2 large eggs OR 150g beans/legumes OR 170g tofu)
If you want to know what your specific needs are according to your current weight & fitness status come and see a Dietitian & Exercise Physiologist from BHNF = the perfect team of health professionals to help determine a nutrition plan that fits your needs & fitness goals.