With all the recent boost in protein talk — especially for those increasing protein consumption to build muscle mass or for increasing physical activity (think about those new years resolutions!)  — it’s probably also a great time to bring up the dangers of protein overconsumption.

While adequate protein intake is incredibly important for your overall health, too much protein can be just as upsetting to the flow of your body.

Alright, but, what exactly does protein overconsumption look like? How do you know if you’re getting too much, too little, or the right amount? What can you look out for just in case you think you may be overdoing your consumption just a bit?

What is Protein?


To understand protein, it’s probably a good idea to start with macronutrients. There are three macronutrients including fat, protein, and carbohydrates. Basically, the big “three” that many nutritionists focus on when it comes to a balanced diet. All macronutrients can be found in almost all food items and each has “their own specific roles and functions in the body and supply us with calories or energy.”

Protein is one of the three macronutrients and happens to be essential for “building muscle mass.” These building blocks are  “composed of amino acids, which are organic compounds made of carbon, hydrogen, nitrogen, oxygen or sulfur.” When you consume protein — found in ample amounts in the foods we eat — it’s broken down to help “fuel muscle mass, which helps metabolism.” Per Jessica Crandall, a spokesperson for the Academy of Nutrition and Dietetics, protein “also helps the immune system stay strong” and it “helps you stay full.”

What is Protein Overconsumption?

NOW Sports Nutrition Pea Protein/Amazon.com

While proper protein consumption based on your individual body design is a hugely important part of a well-balanced diet, overconsumption of protein can lead to dangerous side effects.

In these nutrition-crazed times, there is a slew of popular diets that advocate for a higher protein intake including Atkins, the Zone, the Paleo diet, and even the Keto diet — which is known as a high-fat diet but also emphasizes increased consumption of protein, while reducing carbohydrates dramatically.

Why are all these diets telling you to eat, eat, and eat more of that good old protein?

As we learned above, protein is “an essential part of a healthy diet … [and] … it helps to build and repair muscle, organs, and bones,” while also proving to be “helpful with reducing fat, losing weight, increasing satiety, … and retaining muscle.” All really, really good things!

So, with so many professionals telling you to eat more protein, is there actually too much protein? The short answer is yes.

The Science


Too much of anything is generally not a great thing. This is why I regularly mention “well-balanced” in my articles. When it comes to protein overconsumption, it’s actually somewhat difficult to eat too much if you’re getting most of it from plant-based proteins such as legumes, nuts, and seeds. The problem arises if you’re sourcing protein from animal-based products — such as red meat, poultry, eggs, and dairy — or if you’re consuming extra protein supplements and powders on top of a well-balanced diet.

A 2013 study published in HINDAWI entitled Adverse Effects Associated with Protein Intake above the Recommended Dietary Allowance for Adults concluded thatextra protein is not used efficiently by the body and may impose a metabolic burden on the bones, kidneys, and liver.” On top of that, as referenced to earlier, “high-protein/high-meat diets may also be associated with increased risk for coronary heart disease due to intakes of saturated fat and cholesterol or even cancer.” 

Recommended Daily Intake


Where’s a good place to start when determining if you’re consuming too much protein? Even though every human body is different — from age, to weight, to physical activity, to diet, to physiologic design — the government has outlined Dietary Reference Intake guidelines — “0.8 grams of protein per kilogram of body weight, or 0.36 grams per pound.”

Alright, but most of us don’t generally weigh our food before consuming, in fact, most of us don’t even have a food scale at home, even if we wanted to. So, let’s break this down a bit further. In reference to “sedentary” or “non-active” adults, you should focus on 56 grams per day for men and 46 grams per day for women. If you’re more active, then you’ll need to adjust accordingly.

If you’re looking to really get the perfect ratio for your body and your lifestyle, try using this incredibly detailed protein calculator by Very Well Fit!

Common Symptoms of Protein Overconsumption


It may be easy to identify what too much protein looks like in a diet, but how in the world can you tell if you’re body is getting too much of it? For those of us that don’t have access to nutritionists or dietitians, learning the ins and outs of what protein overconsumption looks and feels like is a great way to keep tabs on that protein intake.

There are actually a handful of symptoms including intestinal discomfort, indigestion, exhaustion, nausea, irritability, and headaches. With that said, these are oftentimes things we experience on a weekly basis due to something bad we ate, stress, or other environmental factors. Therefore, here are some less obvious symptoms that may be telltale signs of protein overconsumption.

Unwanted Weight Gain


A little known fact about protein is that excess protein “is usually stored as fat, while the surplus of amino acids is excreted.” In the beginning, a high-protein diet may lead to a bit of weight loss, but unfortunately, over time, “especially if you consume too many calories while trying to increase your protein intake,” that weight will return.



When it comes to constipation, it generally means you’re not getting enough fiber in your diet. Diets that are rich in protein, generally also restrict carbohydrates as a balance, and therefore, restrict your fiber intake. Certain studies on high-protein diets have shown that more participants reported constipation. Luckily, there’s a simple fix for this! First and foremost increase your fiber and water intake, track your bowel movements, and maybe back off the protein a bit until you smooth things out.



This one is an important symptom to look out for when practicing a high-protein diet. Overconsumption of protein may lead to dehydration, but dehydration will absolutely lead to more unpleasant side effects such as nausea, dizziness, rapid breathing and heartbeat, fatigue, and even fainting.

How does it work?

In an athlete-based study conducted in 2002, it was “found that as protein intake increased, hydration levels decreased.” This may have something to do with the fact that “your body flushes out excess nitrogen with fluids and water … [which] … can leave you dehydrated even though you may not feel more thirsty than usual.”

Bad Breath


Alright, this may be a weird one, but it’s definitely a true one! In fact, the whole “bad breath” myth has been linked to the keto diet as well and scientists have found the connection may have to do with increased protein consumption in conjunction with reduced carbohydrate intake. Researchers believe this may be part of the “metabolic state called ketosis, which produces chemicals that give off an unpleasant fruity smell.”

Unfortunately, there’s not a whole lot you can do to counteract this effect, as it’s a natural side-effect of ketosis. With that said, it’s recommended to “double your water intake, brush your teeth more often, and chew gum to counter some of this effect.”

Higher Cancer Risk


When it comes to the relationship between cancer and a high protein diet, it’s all about the type of protein you’re consuming.

For those practicing a high-protein diet that’s sourced from red meat, you’ll find not only a higher risk of cancer, but also an “increased risk of [other] various health issues.” For instance, “eating more red and/or processed meat is associated with colorectal, breast, and prostate cancer.”

Therefore, while overconsumption of protein doesn’t necessarily lead to cancer, choosing the right types of protein can help decrease these risks.

Plant-Based Foods with Healthy Doses of Protein

Maple Glazed Brussels Sprouts with Quinoa Risotto/One Green Planet

Alright, so we’ve talked about everything under the moon when it comes to protein overconsumption. What about getting appropriate amounts of protein from the plant-based foods we eat? If you take supplements and protein powders out of the equation, what foods should we be eating to get those daily doses without overdoing it? Here are a few high-protein, plant-based sources of protein that are great to integrate into you daily menu!

1. Oats

Savory Mushroom Oats/One Green Planet

These lovely mostly gluten-free grains are a staple for many plant-based eaters. They are not only incredibly filling, but super versatile and wonderfully delicious! Make a super easy overnight oat recipe for work — such as these Blue Raspberry Overnight Oats — or enjoy these grains for dinner with a savory recipe — such as these Savory Mushroom Oats. Plus, oats are not only rich in protein — a half cup “of raw oats has 13 grams” — but they’re also loaded with healthy fibers, magnesium, manganese, thiamin (vitamin B1) and several other nutrients.”

Oats can also be used in many other facets in the plant-based world such as in this Savory Italian Granola, this Warming Turmeric Baked Oats, these Apricot, Almond and Dark Chocolate Cookie Bars, or these Yogi Date Balls.

2. Quinoa

Dark Chocolate Quinoa Crispies/One Green Planet

This ancient seed really is a superfood. When it comes to protein, it kicks many other options out of the water as it’s one of the only sources of “complete proteins,” which means it’s got all of those amino acids that you’re body needs, but can only get from food sources! It’s not only rich in protein — a cup of cooked quinoa “has 8 grams” — but it’s also rich in a variety of other vitamins, minerals, dietary fiber, and antioxidants.

Start your day with these Blueberry and Quinoa Cinnamon Toast Bars, enjoy a quinoa snack like these Dark Chocolate Quinoa Crispies, get your lunch on with this Quinoa Pear Salad (also loaded with fiber), or end the day with this Maple Glazed Brussels Sprouts with Quinoa Risotto.

3. Lentils

Mediterranean Lentil Salad/One Green Planet

Last, but definitely not least, lentils offer a whopping 18 grams of protein per one boiled cup! These little legumes are also “high in fiber, magnesium, potassium, iron, folate, copper, manganese, and various other nutrients.” Plus, they’re one of the most versatile ingredients for plant-based eaters! Lentils can be used to create meatless recipes such as Lentil Loaf with Smoked Paprika Glaze or this Black Lentil Charred Broccoli Shepherd’s Pie, stews and soups such as this Hearty Mung Bean and Lentil Stew or this One-Pot Potato, Spinach and Lentil Dal, or even hearty and protein-rich salads such as this Beluga Lentil Broccoli Salad or this Mediterranean Lentil Salad.

We also highly recommend downloading our Food Monster App, which is available for iPhone, and can also be found on Instagram and Facebook. The app has more than 15,000 plant-based, allergy-friendly recipes, and subscribers gain access to new recipes every day. Check it out!

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