Can Consuming Too Much Protein be Harmful?

Many health and fitness influencers hype up high-protein diets for muscle tone and overall health. While there may be some benefits to higher protein diets, especially if you are an athlete, is eating more protein truly good for fitness and performance?

What are Proteins?

One of the three macronutrients along with carbs and fat, protein is necessary for countless biochemical functions like development and tissue repair (When It Comes to Protein, 2018). The recommended intake of protein is 0.8 grams per kilogram of body weight (When It Comes to Protein, 2018) with slight differences between men and women. People who exercise frequently and need to repair muscle tissue more often may need to consume more. Contrary to popular belief, while protein may help benefit certain aspects of performance, eating too much protein can cause kidney dysfunction and increase muscular cramps.

Damage of Too Much Protein on Kidney Health

High protein intake causes more acid to be produced in body fluids. (Barzel & Massey, 1998 as cited in Delimaris, 2013). Increase in protein intake has also been associated with hypercalciuria, a condition when the body secretes overly calcium-concentrated urine, which in turn decreases calcium retention in the body. Lower calcium has also been correlated with bone loss and increased risk of bone fractures (Hanahan & Weinberg, 2011). Increased calcium in the urine due to hypercalciuria can also cause kidney stone formation (Goldfarb, 1988 as cited in Delimaris, 2013). 

Proteins Association with Muscle Cramps

Calcium is also essential for proper muscle contraction, and having low retention of calcium may dysregulate muscle contraction, increasing muscle cramps. In the same way, the kidneys need more water to filter the acids, taking necessary hydration away from muscles. Interestingly, eating more amounts of protein does not necessarily increase thirst, so people may not feel dehydrated when they actually are. Not realizing they are dehydrated and not drinking enough water increases the risk of muscle cramps.

Conclusion

Associated with conditions like hypercalciuria, bone loss, kidney stones, and muscular cramps, high-protein diets have downsides. Social media influencers often publicize high-protein diets to increase muscle tone and mass, and while protein may help these areas, eating too much protein for your needs may do more harm than good. The research is not to say that eating a high-protein diet is always harmful; however, it is important to learn how your own body functions, and not rely heavily on what works for others.

references

1. Barzel, U. S., & Massey, L. K. (1998). Excess dietary protein can adversely affect bone. The Journal of Nutrition, 128(6), 1051–1053. https://doi.org/10.1093/jn/128.6.1051

2. Delimaris, I. (2013). Adverse Effects Associated with Protein Intake above the Recommended Dietary Allowance for Adults. ISRN Nutrition, 2013, 126929. https://doi.org/10.5402/2013/126929

3. Goldfarb, S. (1988). Dietary factors in the pathogenesis and prophylaxis of calcium nephrolithiasis. Kidney International, 34(4), 544–555. https://doi.org/10.1038/ki.1988.216

4. Hypercalciuria—An overview | ScienceDirect Topics. (n.d.). Retrieved March 11, 2025, from https://www.sciencedirect.com/topics/medicine-and-dentistry/hypercalciuria

5. When it comes to protein, how much is too much? (2018, May 9). Harvard Health. https://www.health.harvard.edu/nutrition/when-it-comes-to-protein-how-much-is-too-much