Chronic kidney disease (CKD) is a condition with increasing incidence worldwide. People suffering from CKD should carefully control the amount of protein they consume and its food source. They should ensure that most of their protein comes from plant sources. A diet that limits animal protein intake is associated with longer life expectancy. Healthy individuals without diagnosed CKD can consume protein without restrictions. Protein consumption of up to 3.5 g/kg of body weight per day has not been associated with kidney damage. This type of diet offers many benefits to patients, including more effective building of muscle mass, a better feeling of satiety after meals, and a reduction in the amount of body fat. However, people suffering from kidney stones and CKD should limit the consumption of animal protein. The use of the DASH (Dietary Approaches to Stop Hypertension) diet in people at risk of kidney stones is associated with a significant decrease in the risk of developing kidney stones, even reducing the risk of developing the disease by 45%. Therefore, there is no one universal answer to the question whether a high-protein diet is beneficial, because different groups of people with their own predispositions may benefit from it, or it may bring them more negative consequences.