I eat a source of protein at every meal and snack. I spread my protein intake throughout the day ( by choice ) to ensure my body is absorbing all its goodness. Did you know, your body burns more calories when you eat protein than when you digest either fats or carbs.
To grow lean muscle tissue it is a good rule of thumb to eat 1-1.5 grams per pound of lean body mass. The pros even eat 2 grams per pound. I try for about 25 grams of protein in each of my meals.
If you're trying to lose weight, you DO NOT ( in my opinion ) need to lower your protein intake since it's the last thing your body converts to fat/energy. Also never cut protein because it simply increases your metabolism which helps with fat burning. Protein is the PRIMARY nutrient to maintain your muscle mass and build muscle when dieting.