How Much Protein Maximizes Muscle Gains

Dr. Peter Attia: Let us go back. We have established a new floor. There is nobody who should be consuming less than 1.2 grams of protein per kilogram per day. What happens as we increase that from 1.2 to 1.6?

Dr. Rhonda Patrick: Great question. This is where I turn to experts like Stu Phillips. He did a great meta-analysis of about 49 controlled trials in adults comparing resistance training alone with resistance training plus supplemental protein. The supplemental protein went above 1.6 grams per kilogram, but the study found that even going from about 1.2 to 1.6 grams per kilogram of body weight per day, people gained about 27 percent more lean body mass and 10 percent more muscle strength than with training alone. It was the same training, with protein added. That is pretty big.

Dr. Peter Attia: I was going to say, that is bigger than I would expect, especially on the strength side.

Dr. Rhonda Patrick: Exactly. On the strength side, they were gaining from the protein itself. If you think about it, we are talking about supply and demand. We are talking about people who are training. That is number one. If we are talking about optimal protein intake, you need to be training. When you train, you break down muscle. You need protein to support the repair and rebuilding of that muscle. It makes sense in that way.

Dr. Peter Attia: Yeah.

Dr. Rhonda Patrick: I was surprised by the strength as well. Once you went above 1.6 grams, there were still increases in muscle protein synthesis.

Dr. Peter Attia: The curve is slowing down.

Dr. Rhonda Patrick: I like the analogy that Stu Phillips uses. If you have a wet washcloth and squeeze it to get all the water out, most of the water comes out at 1.6 grams per kilogram of body weight. You can keep squeezing and still get some water out, but it is marginal. Most people do not care about that difference. Some people do. If you are obsessed with banking muscle mass, you are going to care about it. If you are a high-level athlete, you will need to go above 1.6. That is when you get into the range of 2.0 to 2.2 grams per kilogram of body weight. This applies to people doing a high level of endurance or resistance training because endurance athletes are battling a catabolic state. The evidence suggests that 1.6 grams per kilogram is more optimal, and you can get marginal benefits above that, up to about 2.0 to 2.2 grams per kilogram. Again, that is for people who are really training.

Dr. Peter Attia: There is an analogy here with ApoB and cardiovascular disease. If you look at the epidemiologic data, clinical trial data, and Mendelian randomization data, and plot them on a graph, there is a beautiful graph that we will include in the show notes. It uses LDL-C, but LDL-C and ApoB are easy to view together. On the x-axis, LDL-C descends from 160 to 140, 120, 100, 80, and 60. On the y-axis is cardiovascular mortality. Not surprisingly, as LDL-C goes lower, cardiovascular mortality goes lower.

What is interesting is that you can see different points on the curve where it starts to matter more, and at some point it flattens. You do not get as much benefit from further reduction. We could use the same argument to ask what is optimal. Here lower is better, as opposed to going up with protein.

Peter Libby has done an analysis showing that you continue to see a meaningful reduction in cardiovascular disease as ApoB heads toward 30 milligrams per deciliter. That is really low by most people's standards. For context, 60 milligrams per deciliter is about the fifth percentile at the population level. Thirty milligrams per deciliter is about the level of a child. We are born with relatively low ApoB levels, and as we age they keep going up. That rise is one of the factors driving cardiovascular disease.

The question becomes: how low do you need to go? Should everybody be walking around at 30 milligrams per deciliter? Is that the solution to eliminating ASCVD? Probably not. It depends on your previous exposure. If I have a patient who has already had two stents placed and has a significant burden of disease, you can bet that their ApoB will be at 30 milligrams per deciliter, even if we need three drugs to get there, because their disease burden and lifetime exposure to ApoB have been so high. If I have a 40-year-old with pristine coronary arteries and an ApoB of 60 milligrams per deciliter, I do not think they need to do anything. They are fine. The inability to understand that level of nuance, and when the second squeeze is worthwhile versus when a sloppy squeeze is good enough, is frustrating for someone like me who craves nuance.

Dr. Rhonda Patrick: I agree. I love that analogy, and I think it is perfect. Most people who are training probably get a great amount of benefit from 1.6 grams per kilogram of body weight. That does not mean you cannot go above it and get a little more benefit. This is especially true when you enter an energy deficit. Elite endurance training is one way to be in an energy deficit, but it also applies to people actively trying to lose fat and gain muscle. If you want to lose fat and gain muscle at the same time, you will have to take in a lot of protein.

Dr. Peter Attia: That is another important point. You are still dealing with an asymmetric target, so we tell our patients to aim closer to 2.0. I know that will get people on the anti-protein train losing their minds. I can see the phosphorylation going off as they watch this clip: "How is this guy so irresponsible to tell his patients to eat 2 grams of protein per kilogram of body weight? Did he not hear Rhonda say 1.6 is good enough for most people?"

My patients do not live in labs. They live in the real world. In the real world, you cannot always hit your targets. Some days you do, and some days you do not. Some days you are traveling. Some days you can figure it out, and some days you cannot. If I tell somebody to hit 1.6, one day they might get 1.2, another day 1.7, another day 1.5, and another day 1.9. On average, they might hit 1.6. But how many days were they below versus above? Let us say it is an equal split. We have established the shape of this curve. Every day you are below, the downside is much greater than the upside of being above. The days above do not make up for the days below.

I would rather shift the range so that a low day is 1.6 and a high day is perhaps 2.2. Then you do not have days when you are amino-acid restricted. This is the difference between people who care for patients in the real world and people who write on Substack but do not understand clinical medicine as it applies to managing athletes and people who must fend for themselves at every meal. If you are listening and wondering whether you should eat about 2 grams per kilogram per day, yes, more or less. Then, if you fall short at 1.6, you can be confident that you are okay. If you aim at 1.6 and have a bad day at 1.2, you might take a step backward and will not make up for it the next day.

Dr. Rhonda Patrick: I can tell you from personal experience that it is smarter to aim higher because I am constantly not meeting the target.

Dr. Peter Attia: People look at me like I am a protein-eating machine, which I am not. I have a hard time hitting my goals, too. I am busy, and I miss meals. Sometimes we have a low-protein meal. For whatever reason, my kids might want pasta for dinner, and we literally have pasta and sauce. There is no protein in it. It is very difficult to hit these targets every day if you do not have a chef preparing every meal. I never have a chef preparing my meals unless I am at a restaurant.

Dr. Rhonda Patrick: We mentioned 1.2 grams per kilogram as the minimum buy-in. The 1.6 grams per kilogram is not necessarily just for people who are training. It also applies to older adults who are not training because we discussed anabolic resistance and their need for twice as much protein. What you are suggesting is aiming for 2.0 so that the average is at least 1.6.

Dr. Peter Attia: I never want to fall below that. That is the point. I train every day. Am I training like a madman? No. But seven days a week, I am doing some form of cardio or something in the gym. I know I will take steps backward if I am below 1.6, so I overshoot to make my down day 1.6. If my up day is 2.5 once in a while, who cares? That gets to the next point. Show me the data that eating 2.5 grams of protein per kilogram per day is even remotely harmful. I am still waiting for it. David Allison recently wrote a piece on LinkedIn that was essentially a call for anyone to show human clinical trial data meeting specific criteria. There was nothing but silence.

Dr. Rhonda Patrick: I have not seen human data showing harm either. The most negative data I saw recently came from a study of total parenteral nutrition in ICU patients. The question was whether we should deliver high amounts of protein to these patients. The most negative thing you could say is that it had no benefit.

Dr. Peter Attia: That is interesting. Maybe we should not deliver high-protein total parenteral nutrition into the central veins of critically ill patients, but it did not harm them. If anyone were going to be harmed, I would think it would be people in renal failure.

Dr. Rhonda Patrick: Right. Exactly.