How A lot Protein Is Too A lot? The Dangers of Extra Protein

May 21, 2025

Image of a young muscular woman with her back to the camera, lifting a barbell over her head at the gym. — Protein is a crucial macronutrient for constructing muscle and supporting total well being. However what occurs if you eat an excessive amount of?Credit score: Unsplash John Arano

Protein is the macro du jour, for those who ask well being and wellness influencers. Throughout social media, private trainers and registered dietitians are actively growing numerous recipes the place cottage cheese and puréed beans stand in for extra conventional cream sauces and protein powder is stirred into muffins, cookies, and pancakes. And it’s not simply those who run in wellness circles — in a 2024 survey of three,000 adults, 71 p.c mentioned they had been actively making an attempt to devour extra protein¹.

Right here’s what these influencers gained’t essentially inform you: an extreme consumption of this important macronutrient might find yourself having damaging repercussions in your well being.

However extra isn’t essentially higher, in terms of protein. Relying in your gender, age, and exercise degree, you might already be consuming sufficient.

And right here’s what these influencers gained’t essentially inform you: an extreme consumption of this important macronutrient might find yourself having damaging repercussions in your well being.

Are We Consuming Too A lot Protein?

Protein is a necessary constructing block of our our bodies. As soon as ingested, it’s damaged down into amino acids — lots of that are important to get from meals, because the physique can’t produce them by itself. These amino acids are utilized by the physique to construct or restore muscle, contributing to progress, positive factors, and continued well-being.

However consuming an excessive amount of protein can have damaging well being results, notably in your kidneys. In 2024, researchers from Madrid revealed analysis in Sports activities Drugs indicating that high-protein diets might result in eventual kidney failure, even in in any other case wholesome individuals².

Image of a stack of pancakes topped with greek yogurt, raspberries, figs, and syrup on a cute pink plate. — *The fashionable factor to do lately is so as to add protein powder to all the pieces, from pancakes to cookies. However is there a restrict to the quantity of protein we should always devour?* – Credit score: Unsplash Diana Gentle

The researchers highlighted the really helpful day by day allowance of .83 grams of protein per kilogram of physique weight per day — about 55 grams of protein for a 150-pound lady. For the reason that common protein consumption for People in 2015-2016 was 97 grams for males and 69 grams for girls, it’s very doable that most individuals are consuming sufficient (or much more than sufficient!) protein.

What Occurs If You Eat Too A lot Protein?

Once we devour extra protein than we have to restore our muscle mass and cells, the remaining is usually burned to supply vitality. However burning protein results in the buildup of a waste product often known as urea, which have to be filtered out of the bloodstream by the kidneys.

The extra protein you eat, the extra urea you produce, and the tougher your kidneys should work to filter it out. Even wholesome individuals see damaging negative effects of an excessive amount of protein, based on 2020 analysis within the Journal of the American Society of Nephrology⁴. So is an excessive amount of protein dangerous? Nicely, since 14 p.c of U.S. adults are estimated to have continual kidney illness, these results are undoubtedly price preserving in thoughts⁵.

Different Dangers of Protein Overconsumption

Kidney well being isn’t the one potential aspect impact of consuming an excessive amount of protein. Based on 2016 analysis in Meals & Perform, continual excessive protein consumption (outlined as greater than 2 grams per kilo of physique weight) might additionally result in vascular abnormalities⁶.

Overconsumption of protein may result in weight achieve⁷ or digestive abnormalities like constipation⁸ or diarrhea. It may possibly even trigger the event of dangerous metabolites that may result in gastrointestinal issues⁹, significantly if a high-protein weight loss plan doesn’t additionally comprise satisfactory fiber. And a few research have discovered {that a} greater consumption of protein, significantly animal protein, might contribute to elevated threat of breast most cancers¹⁰ and sort 2 diabetes¹¹.

An Argument in Favor of Extra Protein

Image of a breakfast plate with two slices of toast, scrambled eggs, and several slices of bacon. — *Though it definitely is feasible to devour an excessive amount of protein, there are different consultants who consider most People nonetheless aren’t getting practically sufficient.* – Credit score: Unsplash Natalia Blauth

Not everyone seems to be as cautious of the dangers of consuming an excessive amount of protein. Carolyn Ketchum, writer of the forthcoming The Protein Benefit, notes that whereas the our bodies of youthful adults use protein extra effectively, many consultants consider that older adults may have a bit extra.

“The lack of lean muscle mass begins in our thirties and will increase exponentially over time,” she says, “and because of a phenomenon often known as anabolic resistance, older adults want extra day by day protein to keep up the identical quantity of muscle as youthful people.”

“[Daily protein recommendations] had been by no means meant to be the optimum or goal quantity of any nutrient. As an alternative, it refers back to the least quantity a person ought to devour.”

Carolyn Ketchum, writer of The Protein Benefit

Day by day protein suggestions, she continues, are an insufficient measure of the true consumption of a given nutrient every particular person actually wants, seeing as they’re generalized to the complete inhabitants, no matter age, gender, and exercise degree. “It was by no means meant to be the optimum or goal quantity of any nutrient,” she says. “As an alternative, it refers back to the least quantity a person ought to devour.” In different phrases, the query of how a lot protein it’s best to eat in a day ought to be dealt with on a person degree.

She cites a rising physique of analysis, together with a 2023 analysis evaluate in The Journal of Vitamin¹² and a 2022 analysis evaluate in Ageing Analysis Critiques¹³, that signifies that extra protein — maybe even double the quantity presently really helpful — might be a greater goal for older adults.

Certainly, greater day by day protein consumption has proven to scale back frailty in older ladies, based on 2011 analysis within the Journal of the American Geriatric Society¹⁴. A 2016 report in Meals & Perform indicated that whereas 1.6 g of protein per kg of physique weight was ultimate for individuals doing intense bodily exercise¹⁵, “Lengthy-term consumption of protein at 2 g per kg BW per day is protected for wholesome adults, and the tolerable higher restrict is 3.5 g per kg BW per day for well-adapted topics.”

Protein Isn’t a Magic Bullet

Image of a young woman in a plank position on a yoga mat with a lush green background and a couple of dumbbells around her, pairing protein and exercise. — For those who’re consuming a high-protein weight loss plan however not partnering it with train, you gained’t have the ability to correctly reap the advantages. – Credit score: Unsplash Pablo Merchan Montes

However even Ketchum notes that protein is way from the answer to all our ills. “It’s human nature to need a magic bullet, the one factor that cures all of the ills and solves all the issues,” she says. “Many individuals tend to go overboard. Simply rising protein with out contemplating your different vitamins or getting some train isn’t going to magically make you wholesome and powerful.”

She notes, quite the opposite, {that a} high-protein weight loss plan have to be coupled with train to reap the total advantages. “The connection between protein consumption and bodily exercise is a extremely synergistic one,” she says. “To have interaction in a single with out the opposite is addressing solely a part of the equation. Finished in tandem, they create a optimistic suggestions loop that helps preserve and even construct lean muscle mass nicely into our sixties and seventies.”

The best way to Supply Your Protein

The protein renaissance has led to a plethora of protein powders on {the marketplace}, providing a easy option to incorporate extra of this nutrient into your weight loss plan. However whereas some protein powders are cleaner than others, on the entire, Ketchum is cautious of an over-reliance on these extremely processed sources of the macronutrient.

“There may be nothing inherently mistaken with protein powders, they usually may help fill in any dietary gaps when life will get busy,” she says. However she additionally notes that many are full of sugars and components. Some protein powders have even been discovered to comprise heavy metals like lead. She recommends sourcing clear protein dietary supplements and consuming them mindfully. “Use them along with, fairly than as a alternative for, wholesome excessive protein meals,” she says.

Image of a small plastic scooping spoon filled with an overflowing heap of chocolate protein powder, set on a marble countertop. — *Whereas there’s nothing inherently mistaken with protein powders, many consultants advocate getting most of your day by day protein from entire meals sources equivalent to eggs and meat.* – Credit score: Unsplash Karolina Grabowska

As an alternative, she recommends getting most of your protein from high-quality, entire meals sources like meat, cheese, and eggs (which have lately been vindicated by the FDA to be included within the new definition of “wholesome”). The very best sources of protein are usually pure. Plant-based protein sources like chickpeas, lentils, and beans have additionally been discovered to have much less affect on linked well being points like elevated threat of breast most cancers and sort 2 diabetes. Selecting your protein sources mindfully, and pairing protein with different important vitamins like fiber and wholesome fats, will result in the perfect, most holistic dietary strategy.

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