Vitamin C and Kidney Stones

I always refer to Vitamin C (ascorbate) as the mother of all antioxidants; it heals, repairs and detoxifies the body of extraneous elements among numerous other uses. Since we all have different physiological needs, I usually recommend intakes based on the C-Cleanse Protocol rather than just what is required to prevent scurvy. ( ). This C-Cleanse Protocol that I developed allows for personalized dosing for each individual. I encourage using only fully buffered, fully reduced and recrystallized 100% l-ascorbate; other forms of the vitamin being irritating or unhelpful either due to being synthetic or due to being oxidized in processing and storage.

So, it makes me cringe when I see vitamin C being held in a negative light and especially in connection with kidney stones – a fairly recurrent story at that. Various critics and medical authors through the years have labeled taking large doses of vitamin C “dangerous” because it is thought to produce kidney stones. This was the first argument that critics attacked Linus Pauling with years ago when he wrote his book “Vitamin C and the Common Cold”. The idea seems to stem from the fact that oxalate stone is the most common type (75%) of kidney stone and because a significant percentage of ascorbate is metabolized into and excreted as oxalic acid, it is surmised that this oxalic acid combines with calcium in the urine and deposits as calcium oxalate kidney stones.

The practice of cautioning people against using vitamin C because it produces kidney stones continues even today unfortunately ( even though facts and studies indicate otherwise(Curhan GCWillett WCSpeizer FEStampfer MJ. Intake of vitamins B6 and C and the risk of kidney stones in women. J Am Soc Nephrol. 1999 Apr;10(4):840-5 and Auer BL, Auer D, Rodgers AL. The effect of ascorbic acid ingestion on the biochemical and physicochemical risk factors associated with calcium oxalate kidney stone formation. Clin Chem Lab Med. 1998 Mar;36(3):143-7).

Then what is the real story?

Although ascorbate does increase the production of oxalate in the body, it really does not increase stone formation per se. In fact it works quite the other way. Ascorbate tends to bind with calcium leaving less calcium to bind with oxalate and in effect prevents the formation of calcium oxalate stone.

Another important point – kidney stone formation is largely connected with infection. Extra-tiny microorganisms that live in the urine can, by precipitating calcium and other minerals around themselves, induce the formation of kidney stones.  Large doses of ascorbate are bactericidal and strive to prevent stone formation by removing the bacteria around which stones form.

Ascorbate can also prevent other types of kidney stones. Less common forms of stone for example include uric acid stones (8%), that form in gout, and cystine stones (1%), which can occasionally be formed in children with a hereditary condition and these stones are not side effects of vitamin C.

My advice?

  • Adequate hydration — 8 glasses of 8 ounces of water a day keeps the urine dilute enough that kidney stones cannot form.
  • Adding calibrated ascorbate intake – following the C-Cleanse Protocol further protects the kidneys and bladder from toxins, reduces stone formation risk, and sustains healthy kidney health.