Protein – bodybuilders love it and some seem to believe that more is better. So, they supplement their diets with protein bars, protein powders and shakes, and, sometimes, isolated amino acids – all in the name of growing more muscle. We know that the amino acids from protein are necessary for muscle fibers to repair after a workout. If they can’t repair, they can’t grow. But, is more protein really better and how much protein do you really need??
How Much Protein Do Americans Consume?
The American diet isn’t deficient in protein. In fact, the National Health and Nutrition Examination Survey found that the average female consumes around 70 grams of protein while the average male takes in about 102 grams of protein daily. Current recommendations are that protein makes up between 10 to 15 % of an individual’s diet. Based on this, men are, on average, eating twice the recommended quantity of protein and women are consuming about 30% more than is generally recommended. However, there are subsets of the population who aren’t getting adequate amounts of protein. One such group are women who calorie restrict, especially those who exercise. Another group that falls short are older women.
Do Athletes Need More Protein?
The big question is how much protein does the average person need? The current recommendations don’t necessarily take into account athletes and people who strength train or exercise hard. We know that strength training breaks down muscle fibers and you need amino acids from protein to repair those damaged fibers. But, it’s not just athletes who strength train that need protein. Even if you do endurance exercise, you may need more dietary protein to counteract the catabolic effects of activities like long-distance running.
What does research say about this issue? Unfortunately, it depends on the study. Some studies suggest that athletes don’t need to consume protein beyond the current recommendation of 0.35 grams per pound of body weight and that the current guidelines are liberal enough. However, other studies suggest that up to double this amount (0.7 grams per pounds of body weight) can lead to more favorable training results for athletes. Beyond doubling the recommended amount, there’s little evidence to support additional benefits of consuming more protein.
In reality, there really isn’t a hard and fast answer and how much protein an athletic individual needs and it would likely depend on the type of training, how intense, how long, and how often. What we do know is that the average, sedentary American already gets more than enough protein and that protein deficiency isn’t common in healthy people. The debate is how much protein do athletes really need, especially when consumption is already high. Will adding more make a difference? One study found that consuming more than twice the recommended daily amount didn’t lead to greater muscle protein synthesis. So, there is a point when additional protein doesn’t impact muscle growth.
Is There Harm in Consuming Too Much Protein?
At one time, there was concern that diets high in protein are harmful, that they place too much stress on the kidneys. There is currently no evidence to support the idea that a diet high in protein damages normal, healthy kidneys. Where it could be a problem is in people who have kidneys that aren’t functioning as well as they should. You can actually have mildly reduced kidney function without knowing it. So, it’s a good idea to know that your kidneys are functioning optimally if you consume a high-protein diet.
Too Much of One Macronutrient?
The other problem with a high-protein diet is consuming foods high in protein may crowd other healthy foods out of your diet, especially if you build your high-protein diet around animal foods that are devoid of fiber. One way to get around this is to make at least a portion of the protein you take in from plant-based sources. Good options are nuts, seeds, quinoa, amaranth, tempeh, lentils, chia seeds, and beans. With sources like these, you get protein AND fiber.
Don’t forget that vegetables also contain some protein, although protein from animal sources is more bioavailable. Getting enough fiber is important for a healthy gut microbiome too. Healthy gut bacteria feed on prebiotics, a type of plant-based fiber and this promotes their growth and survival. A healthy gut is important for every athlete!
What about Leucine?
Leucine, one of the three branched-chain amino acids, has special significance for bodybuilders and for anyone trying to retain muscle mass as they age. It’s leucine that activates the mTOR pathway for muscle growth. Studies show a single dose of leucine ramps up muscle protein synthesis in response to resistance exercise. Even without resistance exercise, leucine may reduce muscle loss due to aging. Leucine is most abundant in animal-based foods, like beef, chicken, pork, seafood, and cheese, although soy foods, nuts, and beans have respectable amounts.
The Bottom Line
How much protein is optimal for athletes is still debatable and should depend on how intense and frequent workouts are. Based on the data, it’s safe to consume double the current recommendation for a sedentary person of 0.35 grams per pound of body weight or 0.70 grams per pound. For a 150-pound person, that’s around 100 grams of protein daily. If you do lighter workouts and don’t do high-intensity strength training or long duration endurance training, you probably don’t need this quantity. A more reasonable amount, in this case, would be 20 or 30% higher than the recommendations for a sedentary person.
Don’t forget, consuming a bit more protein has other advantages. Some studies show that diets higher in protein are more effective for weight loss and foods rich in protein have a satiating effect. Plus, studies suggest that as we age and loss of muscle tissue accelerates, getting more protein may help slow this process and prevent sarcopenia. That’s important since having more muscle improves metabolic health as well. Also, if y8ou increase your protein intake, make sure a healthy portion comes from plants as well.
References:
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Mayo Clinic. “Are high-protein diets safe for weight loss?”
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