This Is What Happens to Your Body When You Eat Too Much Protein

You've probably read that it's important to eat plenty of protein to help you build lean muscle and lose weight. After all, protein is the building block of muscle and helps build and repair tissue. Plus, the macronutrient is satiating and, combined with a healthy fat, will keep you full until your next meal.

But it is possible to have too much of a good thing. While the FDA recommends around 50 grams of the macronutrient, the numbers if you want to build muscle are even higher: 0.5 to 0.8 grams of protein per pound of body weight, according to the American College of Sports Medicine. So if someone weights 150 pounds, he or she should eat between 75 and 120 grams of protein. Although every body is different and each person has varying nutritional needs, going much higher than that recommended threshold could have consequences.

We spoke to some experts who broke down what happens to your body if you eat too much protein. If you're concerned about how much protein you should be eating, be sure to visit with a registered dietitian who can help assess your needs.

It Can Make You Gain Weight
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It Can Make You Gain Weight

Sure, plenty of people lose weight on a high-protein diet and it's true that the macronutrient can help you achieve your fat-loss goals. But like with anything, it's possible to go overboard.

"If you enjoy more protein than your body needs and you are exercising daily, it may be stored for energy depending on your level of activity," Adam Perlman, MD, PH, an integrative health and wellbeing expert at Duke University, told POPSUGAR. "On the other hand, excess protein may also be stored in the body as fat while the surplus of amino acids is excreted. The idea behind this is that you can't store extra amino acids or protein indefinitely, and if you consume too many calories and you don't burn them off with activity, you will gain weight."

It Can Mess With Your Kidneys
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It Can Mess With Your Kidneys

For most people with normal functioning kidneys, eating too much protein shouldn't be an issue. But for those with an existing disease, it could be problematic.

When your body metabolizes protein, it produces ammonia, which is turned into a compound called urea. The urea is carried to the kidneys via the blood where it is eliminated in the urine, explained Kristin Koskinen, RDN, LD, CD. If you have a diseased kidney, it may not be able to handle the increase in urea, which can lead to urea build up.

It Could Be Bad For Your Liver
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It Could Be Bad For Your Liver

Koskinen explained that while most healthy adults are able to metabolize protein even at levels that exceed the recommended daily amount, it could be dangerous for someone with a bad liver. To make matters worse, people could have liver damage and not even realize it — non-alcoholic fatty liver disease (NAFLD), which is strongly linked to obesity, affects up to 30 percent of Americans and is largely unsymptomatic until it's detected during a medical exam (via blood work, ultrasound, or radiologic study). It can lead to non-alcoholic steatohepatitis and even cirrhosis.

With a bad liver, eating too much protein can cause a build-up of ammonia. "Ammonia is toxic and will build up if your body can't process an overload of protein or eliminate urea," Koskinen said. "Ammonia in the blood stream can present itself as memory loss, confusion, or forgetfulness. A liver that is diseased with the silent NAFLD may not be able to keep up with the demands of the detoxifying process."

So while losing weight may lower your risk of NAFLD, doing so with a high-protein diet could be dangerous. If you think you may have NAFLD, make sure you visit your doctor to get tested. And as always, visit with a registered dietitian before making any major dietary changes.

It Could Make You Constipated

It Could Make You Constipated

A diet that's high in protein may be lacking in fiber, which is found in fruits, veggies, and whole grains. Not only does fiber keep you full, but it also keeps you regular. Also, some protein powders could cause this reaction in people explained Dr. Perlman, depending on the type of protein and sugars that are used.

To solve this, make sure you are using a protein powder that has added fiber or that you are actively adding more fiber to your diet with beans, whole grains, nuts, and veggies. In a pinch, a fiber supplement such as Metamucil could work, too.