Can You Eat Too Much Protein?

Depending on who you ask, we are either eating “too much” protein, or we need a protein shake after the protein shake to build some muscle or lose weight. In fact, neither one nor the other. Some of us may need more, while others get more than enough, but more is not necessarily harmful. Here’s how to figure it all out.

More than enough is not too much

The last time we talked about protein , we were trying to figure out how much is enough . As a reminder, the National Academies’ Department of Health and Medicine says that 98 percent of us get enough protein if we eat 0.36 grams of protein per pound of body weight. This number, the RDA , is the basis for textbooks and government guidelines. This gives 54 grams for the average woman who weighs about 150 pounds, or 72 grams for the average man who weighs about 200 pounds.

Most Americans eat more. In this USDA report , based on a large survey in 2010, men ate an average of 98 grams of protein per day and women ate 68. Protein intake was low in some older adults and some teenage girls, but most we easily meet the requirements of the textbook.

Such studies have led to a kind of myth that we all eat “too much” protein . But this is a delusion. It would be more correct to say that on average we consume more than enough protein. This is a good thing! After all, we wouldn’t want to eat less than enough.

So this number we started with – 0.36 grams of protein per pound of body weight, sometimes written as 0.8 grams per kilogram – is the minimum. And this is only the minimum for people with an average sedentary lifestyle. If you exercise a lot or are trying to lose weight, it makes sense to eat more .

Even if a marathon runner or bodybuilder is healthy with a protein intake close to training, they may be even healthier or better able to perform their sports by consuming more protein. Again, this is not too much ; it is within the bounds that their body can be put to good use. This range goes up to 0.82 g / lb, depending on the athlete and their sport. That’s 123 grams for a 150 pound person or 164 grams for a 200 pound person.

Extra protein just means extra calories

You will notice that even the higher levels we discussed fall within the 1 gram per pound “rule” that bodybuilders and some other athletes love to repeat . You don’t have to look far to find people trying to eat 200 or even 300 grams of protein a day , based on the theory that more is better. The extra protein won’t harm you, but it can make you gain weight.

This is what is happening in your body. We eat protein so that we have the amino acids (building blocks) to build our own protein-containing body parts. This includes muscles, as well as hair, skin, enzymes, and all kinds of small components in our cells. But we need so many things. Eating an extra 100 grams of protein will not force your body to build another 100 grams of muscle and hair. Instead, this extra protein is just … food.

Just as we can burn fat or carbohydrates for fuel, we can burn protein. And just as we can convert these nutrients into fat for storage, we can do so with protein. To burn or store protein calories, our bodies must remove the nitrogen-containing “amino” portion from each amino acid, and the most convenient way to excrete this nitrogen is in the urine. This has given rise to the strange myth that it is impossible to eat too much protein because your body will “pour out the excess.” No, protein calories are still stored or burned like any other calories. Your urine simply contains an indicator that you have eaten some of your calories as protein.

This is disappointing if you are trying to lose weight: you may have had the same calories in a different form that you may have liked better. Perhaps grilled cheese or a small dessert instead of a hundredth dry chicken breast.

The “dangers” of high-protein diets are exaggerated

The same government document that outlines the protein recommendations also contains a note on the “adverse effects of overconsumption.” It says there is no protein level that is associated with side effects. Instead, they recommend that protein make up 10 to 35 percent of an adult’s calories. They chose the lower number to provide enough protein to meet your daily requirement, while the upper number is essentially as much protein as you can eat while still getting the recommended fats and carbs.

So if the National Academies don’t think high protein intake is dangerous, then who thinks it? These are mostly non-science people and groups such as the Vegetarian Physicians’ Committee for Responsible Medicine . They call kidney disease, cancer and kidney stones deficiencies in a high-protein diet.

But remember that protein is not the same as meat . High consumption of red and processed meats has been linked to cancer , but that’s not a reason to avoid other protein sources like chicken, tofu, beans, or whey powder. The link to kidney stones is also dubious: animal protein appears to be linked to stones, but the American College of Physicians has been unable to find enough evidence to recommend a low protein diet for people prone to stones.

And the idea that too much protein will “load your kidneys”, as the PCRM claims, has also been refuted. As Chris Kresser points out, people who donate a kidney are not at risk of kidney disease, although their remaining kidney works twice as hard. This makes the idea of ​​”stress” challenging. Low protein diets do help people who already have kidney disease , but there is no evidence that high protein levels are bad for people who have healthy kidneys in the first place .

Find your sweet spot

Since there are no strict protein restrictions for healthy people, you need to figure out how much protein is right for you . Use your activity level and goals ( along with our guide ) to determine what your minimum should be. This is your “enough”. Watch what you eat to make sure you’re getting close to that amount. Tracking is especially helpful if you are on a restrictive diet, be it a paleo or vegan diet, or simply very low in calories, as you may not be aware of what you are missing.

Then, to find your “too much,” look at your calories. Does 300 grams of protein (that’s 1200 calories) really fit into your diet? If you really like the taste of tuna and protein shakes, it’s none of our business if you ditch the pigs. But if a high protein diet is more of a problem and more calories than it’s worth, then there is too much of it.

Illustration by Sam Woolley .


Leave a Reply