By Brad Dieter
There are lots of strange “facts” about protein. What’s true and what’s bro-science? Learn which protein myths need to die (plus research to back it up!)
Protein is my favorite macro.
Because steak is awesome, protein shakes are the greatest invention of the 20th century, and I like building muscle.
So naturally, I get a little frustrated when people spread falsehoods about my favorite macro.
Now, seeing that I am a scientist and I value the truth, I think I should stand in on behalf of protein and defend it against some of the popular myths about it.
1. Protein Wreaks Havoc on your Kidneys
“Go easy on the protein shakes bro, you are going to wreck your kidneys.”
If I had a dollar for every time I heard or read that protein was going to hurt my kidneys…. well… I would probably be retired and blogging full time.
Recently, Dr. Jose Antonio did a study to answer the following question, “Basically, if we stuff you full of protein (like 4g/kg a day) what happens to your kidneys and your blood tests?”
Well, it turns out that if you take healthy young men and cram them full of protein and have them lift weights, their kidneys are just fine and it had no effect on their blood work1.
These people ate about 270 grams of protein a day for 8 weeks and their kidneys and blood were just fine.
This myth really, really needs to die.
2. Protein Makes Your Bones Brittle
For some reason some doctors and scientists got some nonsense in their heads about protein making your blood acidic and that it caused calcium to be “leached” from your bones to buffer out your blood, effectively making your bones brittle and weak. Turns out, that is entirely untrue, the hypothesis has been refuted by several lines of evidence.
First, a study directly addressing this question found that a diet high in protein had no change in biomarkers of bone resorption or formation, indicating that a high protein diet has no adverse effects on bone health2. This evidence supports the notion that high-protein diets are not detrimental to bone health.
Second, we know that high-protein diets actually increase calcium absorption in the digestive tract, and increased blood calcium elicits calcitonin release from the thyroid and promotes calcium deposition in bone tissue. To this point, there have been several studies supporting the idea that increased intestinal calcium absorption due to high-protein diets may actually improve bone health3,4,5.
3. High Protein Diets make you Gain Weight
I thought of a lot of clever ways to put this, but to quote one of the most prolific high protein diet researchers in the field (Dr. Jose Antonio):
“You gain weight. No shit. If you lift weights and eat a bucketful of protein, you will likely gain lean body mass. But here’s the kicker. If all you did was overeat on protein (i.e., in our study, subjects overfed on whey protein), you would likely lose weight. And not muscle mass my friend. You’d lose fat”.
No joke, in 2 separate studies where they overfed people protein6,7, those who took in extra calories from protein lost weight. Don’t believe me? Here is the data (data is adopted from reference 6.)
If you look at the data, taking in extra calories from protein actually causes you to lose weight, specifically body fat.
I guess we can bury this myth as well.
4. High Protein Diets Make You Stink
Another common myth that circulates around the interwebz is that high protein diets make you smell funny. Well… this can be true but not for the reasons most people think.
First, in a lot of the anecdotal stories of people smelling bad from high protein diets, it is because they immediately assume that to eat high-protein you have to be low-fiber, low-carb, and low-fat. So yes, if you eat a high protein, low-carb, low-fat diet, your sweat might smell like ammonia due to all the urea you sweat out when you train hard.
There is a really easy solution to that. Eat some carbs and eat some fat.
There have also been some reports of high protein diets causing people to have bad breath… I hear toothbrushes and toothpaste work great for keeping your mouth clean and smelling fresh.
Step Your Knowledge Whey Up
You may not be the biggest and brightest bro on the block, but after reading this article, you should be armed with the knowledge to combat even the vilest science offender.
Exercise science is an ever-evolving field, so in order to keep up with the latest research, you must be willing to set aside your personal biases in order to question long-standing myths.
Don’t just take my word for it though, dig into the studies and take the time to think critically. Information can’t always be spoon-fed and if you want the full picture, it’s going to take time to dissect the details.
- The effects of a high protein diet on indices of health and body composition – a crossover trial in resistance-trained men
- A diet high in meat protein and potential renal acid load increases fractional calcium absorption and urinary calcium excretion without affecting markers of bone resorption or formation in postmenopausal women.
- Diets higher in dairy foods and dietary protein support bone health during diet- and exercise-induced weight loss in overweight and obese premenopausal women.
- Protective effect of high protein and calcium intake on the risk of hip fracture in the Framingham offspring cohort.
- Dietary protein and skeletal health: a review of recent human research.
- A high protein diet (3.4 g/kg/d) combined with a heavy resistance training program improves body composition in healthy trained men and women – a follow-up investigation
- The effects of consuming a high protein diet (4.4 g/kg/d) on body composition in resistance-trained individuals