Can you eat too much protein?

It seems like all anyone on social media is talking about right now is how to get more protein on your plate — add collagen powder to your coffee, double-up on the chicken in your lunch salad, snack on cottage cheese constantly. But while getting enough protein is definitely important for your health, there’s a question that’s not really being addressed: Is it possible to go overboard? Here’s whether there can be too much of a good thing, how to figure out the right amount of protein for you, and easy ways to get your intake where it needs to be.

What is protein?

Protein is one of the three macronutrients (the other two are fat and carbohydrates) and it’s critical to the structure and function of the body. “The primary purpose of protein is to build and repair the body’s tissues, such as muscle, bone, and skin,” says Keri Gans, RDN, a registered dietitian in New York City. It can be found in both animal and plant-based foods, with some key distinctions between the two.

Animal-based protein

Animal-based proteins are those derived from meat — chicken, pork, beef, and fish, along with dairy products like milk and eggs. Protein from animals may be easier to digest and get used more efficiently by your body than their plant-based counterparts. This is likely because animal-based proteins offer all of the essential amino acids, which are essentially building blocks for your body. Amino acids are involved in a huge range of functions in the body, helping metabolize energy, produce hormones, and create antibodies for the immune system — and some can only be gotten through food.

Plant-based protein

You can find protein in many plants: beans and legumes (like lentils), soy (like tofu and tempeh), nuts, seeds, and some types of grains, such as quinoa and wheat. These foods may not offer the full range of amino acids that meat does, but they have an important benefit: Unlike animal-based proteins, “plant-based protein provides a great source of fiber and antioxidants,” says Jennifer Maeng, R.D., a registered dietitian and founder of Chelsea Nutrition in New York City.

Benefits of protein

Protein is essential for your overall health, since it’s in charge of building and repairing muscle and can help manage weight and prevent disease. Eating enough protein is even more critical as you age, since you tend to lose muscle mass over time. Here’s a deeper look at what protein can do for you.

Muscle building and repair

Protein is critical for muscle repair — especially if you work out regularly. When you exercise, you can create microscopic damage in your muscles. The amino acids in protein will help mend and build back the muscles. This explains why adding more protein to your diet alongside resistance training can lead to significant increases in muscle strength and muscle mass. Additionally, “an adequate protein intake may help decrease the loss of muscle mass as we age,” says Gans. In fact, a study in Clinical Nutrition found that the more protein people ate, the less muscle loss they experienced in middle age and beyond.

Weight management and satiety

Boosting your protein intake is often brought up as something that can help you lose weight, and for good reason. Eating protein “may help with satiety, lowering the risk of overeating,” says Gans. In other words, you feel fuller for a longer period of time. “Protein-rich diets stimulate the release of anorexigenic hormones like GLP-1 in the short term, which enhance feelings of fullness,” says Maeng. On top of that, she says, protein requires energy to process, meaning you burn calories just to digest them.

It seems focusing on eating protein for weight loss might be more helpful than changing your intake of fat or carbs. One meta-analysis found that high-protein diets — meaning those in which more than 25% of your caloric intake comes from protein — leads to greater reductions in body weight and fat mass compared to low-fat diets. It can also help maintain weight: A 2017 review found that a high-protein diet can protect against fat gain when you’re taking in more calories than you’re burning — especially when combined with resistance training.

Disease prevention

Protein supports the immune system by providing those important amino acids, which help produce white blood cells and create antibodies. On top of that, protein also improves your overall health by helping you hold on to muscle. One meta-analysis found that low muscle mass was associated with a higher mortality risk of all causes, cardiovascular disease, cancer, and respiratory disease. However, the type of protein matters, since “overconsumption of processed meat and saturated fat are associated with adverse health outcomes like cardiovascular disease,” says Maeng.

How much protein do you need?

The Recommended Daily Allowance is 0.8 grams of protein for every kilogram of body weight. Like many nutrients, protein needs depend on personal factors like your sex assigned at birth and your age. Another way to think of it is that women over the age of 13 should be eating at least 46 grams of protein a day, whereas men over 18 should be getting 56 grams a day, according to the most recent Dietary Guidelines for Americans. “The amount of protein consumed can vary depending on several factors, including health status and activity levels,” says Gans. “The more active we become and the older we get, the higher the protein intake needed.” For instance, if you run regularly or are looking to build muscle with a strength-training protein, then you might want to increase your protein intake.

Side effects of too much protein

As healthy as protein is, going overboard on it can end up stressing out your kidneys, which “are in charge of filtering waste products from protein metabolism and can be strained by excessive protein intake, potentially leading to dehydration and kidney issues,” says Maeng. A study also found that high-protein diets could lead to bone loss (breaking down proteins can increase the amount of acid in the body, which could lead to calcium loss). And eating a lot of meat that’s high in saturated fat is linked to a higher risk of cancer and faster progression of heart disease. (This can be helped if you choose leaner cuts of meat and trimming visible fat when you eat red meat.) Another reason Maeng says not to make protein too much of your diet: You get less of other key nutrients, like fiber, which could contribute to digestive issues like constipation.

How much protein is too much?

There is no hard-and-fast rule about how much protein is too much — individual needs vary and you may need more protein if you’re very active or taking certain medications like a GLP-1. The National Academy of Sciences does recommend capping protein at 35 percent of your daily diet, though. So if you’re eating 2,000 calories a day, that means not eating more than 175 grams a day. If you are curious whether or not you’re eating too much protein, talk with your healthcare provider.

How to get the right amount of protein

To make sure you're eating enough protein, you’ll want to factor in your lifestyle and activity levels — and consider your long-term goals. If you’re hoping to put on muscle or are losing weight and want to avoid losing too much muscle alongside fat, then you might want to eat more. It’s similarly important to get protein from a variety of animal and plant sources and choose lean protein whenever possible.

Calculating your individual protein needs

You can start with the RDA minimum of 0.8 grams of protein for every kilogram of body weight. So a person weighing 140 pounds would need roughly 50 grams of protein a day. However, Gans notes that this amount mainly serves to prevent a deficiency — so eating more than this is a good idea, so long as you don’t go over the 35 percent of your total diet limit mentioned above. A good guideline: “Ideally, one should consume between 15 and 30 grams of protein per meal,” she says. Protein-rich snacks are also a good idea, since they can help keep you full. If you’re unsure how much protein you should be aiming for, a registered dietitian can help. WeightWatchers members have access to personalized nutrition advice from RDs as part of their membership.

Timing of protein consumption

You should be eating protein throughout the day — not waiting until dinner to try to cram it all in. One recent study found that a protein-rich breakfast could help you feel fuller through the morning and even improve concentration. It’s also a good idea to eat protein after you work out in order to help your muscles recover. After you exercise, “protein should be consumed within two hours to support muscle protein synthesis, the process of repairing and growing muscle fibers,” says Gans.

Choosing the right protein sources

When you’re exploring how to get more protein in your diet, it’s important to know that both animal and plant sources have advantages. “Animal protein provides a complete amino acid profile, while plant protein is rich in fiber and micronutrients like antioxidants,” says Maeng. “On the other hand, animal protein may contain saturated fat, while plant protein can miss out on one or more essential amino acids.” For that reason, Maeng recommends a variety of high-protein foods from both plant and animal sources to “ensure you get all the essential amino acids as well as a variety of micronutrients,” she says. Go for lean meats — like chicken, turkey, and fish — eggs, low-fat dairy products, beans, tofu, nuts, and seeds.

The bottom line

Everyone’s ideal protein intake is different based on sex, age, activity level, and health goals, but most people should eat 0.8 grams per kilogram of body weight a day. Your individual needs may vary depending on age, sex, activity level, and more. While getting enough protein is important for building muscle and other important bodily processes, having too much of it — more than 35% of your total diet — can cause more harm than good since it can crowd out other potential nutrients. If you’re trying to eat more protein, go for a mix of plant and animal sources to make sure you’re getting all the amino acids your body needs as well as fiber and vitamins.