I cannot find the study currently, but I believe the Mayo Clinic took 3 groups and put them on different levels of protein while monitoring muscle synthesis. The groups were on 0.7g per lean mass, 1.0g per lean mass, and 1.4g per lean mass. There was no notable difference between the groups in muscle synthesis. I think a non-athlete is recommended to get roughly 0.3g per lean mass to maintain mass.
That being said, there is a lot of misinformation on this subject. I strength train and shoot for 1.0g per lean mass pound and do not worry if I fall a bit under at times. I'm a small guy at 5'8" and 165 and shoot for a lean mass of 155. I noticed a positive difference in recovery when I started taking whey protein/creatine before a work out, BCAA's during a workout, and a mix of whey/casein/carbs after a work out.
Your fat loss is just a function of your overall calorie intake versus expenditure. Hard
I decreased from 180 to make strength gains in 165 pounds over the span of 2 months by creating a calorie deficit. To maximize your muscle growth and strength gainsI kept my macronutrients balanced (40% protein, you might consider putting your fat loss goals on the back burner35% carbs, 25% fat). I only recommend this for the short term because you are training have been able to maintain my lifts. I have kind of stalled out for a strong man contest where body fat % is not importantcouple of weeks but had a vacation and an out town trip that interfered with my nutrition. :)