This is part 2 in my series on factors that went into determining this cut, and that hopefully others can use in determining their own cutting (or bulking) or just general nutritional needs.
I’ve known for a while I probably end up eating more protein than I need. You don’t need nearly as much protein as you probably think you do. Additional protein past your needs actually causes an increase in enzymes that aid the use of protein breakdown for energy, and can be counter-productive. Here's a great study on the topic. Basically what was found is that even heavily trained athletes achieved nitrogen balance around 0.7g per pound of bodyweight, so around 140g for a 200 lbs. person. Furthermore, maximum additional synthesis occurs about 25% above balance, so about 170g for a 200 lbs. person. Not only that, but beyond the point of reaching nitrogen balance ammonia started to build up at an increasing rate in the subjects’ systems. Past about 230g every single gram of protein was converted entirely into ammonia (this is for ‘natural’ athletes, gear use could enhance this probably), “At a protein intake of 230g/day the body’s ability to convert ammonia to urea is saturated”. For reference nitrogen balance means you’re not wasting away basically; positive nitrogen balance indicates growth, negative implies wasting away in some manner. Now there are studies that found when giving people 170g of protein, and another group 250, the 250 group actually built slightly more muscle, but it wasn’t done on a gradient, so who knows where the difference was. Also, additional protein may be sparing of already built muscle, so it may not get used to build new muscle, but may prevent it from being broken down. Your body is basically a set of thermostats, and if you’ve been over consuming protein your body has raised levels of enzymes that cause it to break down protein for energy; even if you stop now it’s going to take a week or two for that ‘thermostat’ to come down, so you may experience a slight bit of catabolism. You can probably offset this with leucine. Studies also show the much higher synthesis effect of leucine, which greatly reduces the level needed for balance and anabolism. So for instance 170g of protein and maybe 20g of leucine would be better than 300 grams of random proteins, accruing ammonia and building up enzymes that destroy amino acids for use as energy
As for worrying about muscle loss, consider this: 3 net grams of protein (over base need) a day are needed to build a pound of muscle tissue per month. Building muscle is more about how to stimulate synthesis of the amino acids and peptides in your system into muscle, as opposed to the amount of protein you consume. Just from the raw amount of aminos in your body right now, you could build a couple pounds of muscle immediately, daily. If you’re curious about the numbers: 1 pound is 454 grams. One pound of muscle tissue is 70% water, 20% contractile protein and 10% miscellaneous lipids, etc. Again, these are rough numbers, and vary source to source a bit. So that’s about 90g of protein in one pound of muscle, average that need out over a month and you have about 3g per day, if you want to think of it like that. In other words, you have plenty of amino acids in you right now. What you need is to drive that synthesis of muscle tissue. Which brings me back to the amino acid leucine, which is really the trigger that tells your body to synthesize protein (in other words build muscle). The take home point here, on days when I really inflict a lot of damage on muscles via high rep sets, I’ll probably get close to 200g of protein. But the lower rep higher weight workouts I do more often, during those I’m just not inflicting enough damage to justify getting that, and I’m going to be scaling back on the protein.