Spanish scientists have found that excessive protein intake influences the formation of kidney stones. Why? Because it reduces the amount of citrate in the urine. Citrates are substances that prevent calcium in the urine from forming into crystals. If there is not enough citrate, stones can form, which cause severe pain.

Studies have shown that a high-protein diet lowers the urine pH value, meaning that urine becomes more acidic. This additionally increases the amount of calcium in the urine, which further raises the risk of stone formation. Scientists have found that people who stick to these kinds of diets for longer periods have up to a 25% higher risk of developing kidney stones compared to those who eat a more balanced diet.

In addition to the kidneys, the liver is also burdened. If the body gets too much protein, it must break them down and eliminate their metabolic waste products, which means extra work for the kidneys and liver. The U.S. National Institutes of Health (NIH) warns that prolonged high-protein intake can lead to dehydration, since the body needs more water to eliminate excess nitrogen compounds.

There are even more dangers...

Some experts say that such diets are problematic for bones as well. A high-protein diet is said to increase the excretion of calcium from bones, which in the long run can lead to osteoporosis. A Harvard University study showed that people who consume high-protein diets have bone density that is 10% lower than those who eat a more varied diet.

However, it’s not all black and white. Proteins are essential for the body, since they build muscles, hormones, and enzymes. The problem arises when there’s too much of them and the body cannot use them efficiently. The World Health Organization (WHO) recommends that adults consume about 0.8 grams of protein per kilogram of body weight per day. This means that a person weighing 70 kg needs about 56 grams of protein per day. Those on high-protein diets can consume two or even three times the recommended intake daily, which can already impact health.

One of the myths of high-protein diets is also that they are good for weight loss. It's true that protein makes you feel fuller for longer, but in the long term the body also needs other nutrients such as fiber and healthy fats. A study from the University of Sydney showed that people who follow such diets often regain lost weight within two years after ending the diet.

If you want a safe and healthy diet, balance is key. Eat enough protein, but not at the expense of other nutrients. For healthy nutrition, experts recommend a combination of plant and animal protein sources, together with sufficient fiber and vitamins.

If you are considering a high-protein diet, consult with a nutrition specialist, who will help you balance your menu and avoid potential risks.