Nutrition for athletes: protein facts vs. protein myths

Protein is a critical component of an effective nutrition plan, and getting your protein right can make a big impact on your health and performance. So in this article, we’re going to examine and summarize the evidence-based answers from a new study to 12 different questions that are critical for hard-training athletes. We’re also going to stick with the most important questions so that you can put these ideas into practice as appropriate.

It’s important to understand that the data and recommendations that follow are not my personal opinions, or even the personal opinions of the researchers who authored this newly published paper(1). These recommendations arise from their assessment of the protein nutrition literature after a comprehensive analysis of the available evidence. Of course, we all vary, and it’s quite possible that your individual experiences may be somewhat different from the suggestions. If that’s the case, and you’re happy with the outcomes you’re experiencing, feel free to continue on your current path. However, you feel that your protein nutrition might be improved in any way, what follows is recommended reading!

Q1: Is protein harmful to your kidneys?

No. Protein, even at high intake levels, is not harmful in healthy populations. There is no evidence that high intake levels lead to kidney damage in the short-term or the long-term. Specifically in athletes, high protein intakes have not led to negative changes in kidney activity, and no long-term protein supplement studies have ever demonstrated adverse effects. This is even true in studies where individuals were consuming extremely high levels of protein. High-protein diets have also been shown to positively impact health markers in type 2 diabetics and pre-diabetics, all without any negative impact on kidney function.

Q2: Does consuming ‘excess’ protein increase body fat mass?

There’s an old saying that extra protein just turns to fat. But this does not appear to be the case. There are several studies that show that very high levels of protein do not lead to increases in fat mass in spite of increased calorie consumption as a result of the increased protein intakes. It appears that an excess of fats and carbohydrates is what contributes to weight gain as opposed to protein. During hypocaloric (dieting) conditions, increasing amounts of protein do not lead to increases in fat mass, but instead lead to increased preservation of fat mass.

Q3: Can dietary protein have a negative effect on bone health?

There is a belief that protein intakes can increase the acid load of the diet, which in turn strips calcium from the bones, which is then excreted out via the urine. Regardless of this hypothesis, multiple studies and meta-analyses have concluded that bone health is not compromised by higher protein diets. In fact, protein is a critical component of bone, and increased dietary protein may promote bone health rather than harm it. High protein diets have been associated with higher bone mineral density, fewer hip fractures, and slower bone loss in aging populations.

Q4: Can vegans and vegetarians consume enough protein to support training adaptations?

There is a lot of controversy about protein sources. Animal-based protein does contain a higher percentage of the ‘essential amino acids’ and the amino acid leucine, both potent simulators of muscle protein synthesis. So when compared head-to-head, animal protein sources stimulate greater muscle protein synthesis than plant protein sources when the same amount of protein is consumed.

However, this does not mean that vegan or vegetarian sources can’t get the job done. The researchers suggest individuals can compensate for the inferiority of plant-based sources by consuming 20-40% of calories as plant protein, thus matching the positive benefits of animal-protein sources. Indeed, multiple studies have shown that plant protein can support positive training adaptations, provided sufficient protein is consumed.

Q5: Is cheese or peanut butter a good protein source?

While peanut butter and cheese can provide good amounts of protein, the problem is what comes with that protein. To consume a sufficient amount of protein through either source, you’ll need to consume a large number of calories in the form of fat as well, which can negatively impact body composition. Specific to peanut butter, it is a plant protein, and as we just discussed, even more protein must be consumed to provide the same anabolic impact. This will require consuming even more calories. If you can handle or need the extra calories, these options can work. Otherwise, alternative choices may be more effective.

Q6: Does consuming meat (ie animal protein) cause unfavorable health outcomes?

This is a controversial topic as the evidence is mixed and nuanced. It does appear that processed meat can potentially result in unfavorable health outcomes. By contrast, it appears that white meat and fish can lead to positive health outcomes. What’s less clear is the impact of red meat on health. There is some epidemiological evidence that shows it may have a negative impact on health and some that shows it may not, but it is very difficult to tease apart the impact of lifestyle factors. Further, any potential impact of red meat appears to be very small. If you are looking for definitive answers, unfortunately they are not available at this time.

Q7: Do you need protein if you are not physically active?

While you’re most likely an avid athlete if you’re reading this, there may be periods of your life when sport is on the backburner. Protein is a critical component of numerous cellular process and integral component of all body structures. From a health and longevity standpoint, sufficient protein powerfully promotes better body composition and the preservation of muscle tissue, both of which are critical for a long and healthy life. Even if you’re not training, protein matters. And if you’re experiencing an injury which is hampering your training, consuming sufficient protein is going to help preserve muscle even if you’re not training.