The Claim

Patients with pre-existing chronic kidney disease who consume high-dose vitamin C supplements (≥1 g/day) experience increased levels of oxalate in the kidneys due to reduced renal excretion, leading to secondary hyperoxaluria and renal oxalosis.

Source: A case report of renal oxalosis and secondary hyperoxaluria due to chronic high vitamin C consumption

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
30score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

Cause and effect
1 study reviewed
In plain English

In people with chronic kidney disease, taking high doses of vitamin C (1 gram or more per day) leads to higher levels of oxalate in the kidneys, which can cause oxalate deposits and kidney damage.

See the scientific wording

Patients with pre-existing chronic kidney disease may be at increased risk for secondary hyperoxaluria and renal oxalosis when consuming high-dose vitamin C supplements (≥1 g/day), due to reduced renal excretion capacity and increased oxalate accumulation.

Why this might work

When someone with damaged kidneys takes large amounts of vitamin C, the body converts the extra vitamin C into oxalate in the liver. The kidneys, already unable to filter well, cannot remove all this oxalate. The oxalate builds up in the urine and forms hard crystals that stick to kidney tissue, causing damage.

Verified mechanismbased on 1 study

What the research says

1 study
  1. Study: A case report of renal oxalosis and secondary hyperoxaluria due to chronic high vitamin C consumption

    A man with weak kidneys took a lot of vitamin C pills every day, and his kidneys got worse because too much oxalate built up and formed crystals. When he stopped taking the pills, his kidneys got better. This shows that people with kidney problems should be careful with high-dose vitamin C.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.