The pH of urine, also known as pH, is weakly acidic under normal dietary conditions, about 6.5, with a fluctuating range of 4.5-8.0, within which it is basically fine. Under some physiological or pathological conditions, the pH level may decrease or increase. For example, a meat-based diet will lower the pH, a respiratory acidosis pH will lower during sleep, and a urine pH will lower during strenuous activity, stress, and when starving or sweating profusely. If a plant-based diet is predominant, the pH will often be greater than 6. The pH will increase after a meal when gastric acid secretion increases and acid secretion in the urine decreases. The presence of respiratory or metabolic acidosis, diabetic ketoacidosis, as well as gout, fever, starvation, emphysema, cystine stones, urinary tuberculosis, nephritis, metabolic alkalosis, severe diarrhea, etc. will lower the pH. Respiratory or metabolic alkalosis, bacterial decomposition of urea, renal tubular acidosis, prolonged vomiting, infectious cystitis, pyelonephritis, the urine is prone to alkalinity at this time.