Urine and saliva pH levels are largely influenced by diet, localized microbial activity, and renal tubular function, rather than serving as an accurate reflection of the body's overall systemic acid-base balance.
The claim that urine and saliva pH accurately reflect the body's systemic acid-base balance is scientifically unfounded and refuted by physiological evidence. Blood pH is tightly regulated within a strict range (7.35-7.45) by the lungs and kidneys, whereas urine and saliva pH fluctuate widely based on localized factors, diet (PRAL), hydration, and oral bacteria. While papers like [0] and [5] discuss urine pH as a reflection of renal acid excretion or dietary load, they do not validate it as a measure of systemic blood acid-base status, and alternative wellness claims promoting 'alkaline diets' based on urine or saliva test kits lack clinical validation regarding systemic pH.