By Independent News Roundup
A major new review paper titled, High-dose vitamin C: A promising anti-tumor agent, insight from mechanisms, clinical research, and challenges, analyzed 150+ studies and found that when vitamin C reaches true pharmacologic levels (20–30 mM), it behaves like a targeted, tumor-selective therapy — something past trials missed by under-dosing. The evidence base spans decades of laboratory, animal, and early-phase clinical research.
The authors outline four major anti-cancer mechanisms of high-dose vitamin C — pro-oxidative tumor cytotoxicity, epigenetic reprogramming, suppression of oncogenic signaling pathways, and powerful immune activation.
For a therapy this safe, inexpensive, and mechanistically potent, the findings are striking. Here’s what they found:
When plasma levels reach the 20–30 mM range, vitamin C switches from antioxidant to pro-oxidant, generating hydrogen peroxide and hydroxyl radicals inside tumors — while sparing normal tissues.
Tumors are uniquely vulnerable because they accumulate:
This combination creates a selective chemical trap that cancer cells cannot escape.
The review highlights a major vulnerability: KRAS- and BRAF-driven colorectal, pancreatic, and lung cancers are selectively disrupted — even destroyed — by pharmacologic vitamin C.
These mutations cause:
This makes the cancer cells especially sensitive to vitamin C–induced metabolic collapse.
A Phase III clinical trial even reported significantly improved survival in KRAS-mutant colorectal cancer patients when high-dose intravenous vitamin C was added to standard therapy.
Vitamin C is a required cofactor for the enzymes that degrade HIF-1α, a central regulator of tumor aggressiveness. At pharmacologic doses, high-dose intravenous vitamin C shuts down:
Very few agents directly dismantle this survival pathway.
Pharmacologic vitamin C reactivates TET enzymes, reversing abnormal DNA hypermethylation and restoring tumor-suppressor gene expression.
Multiple studies show induced differentiation and suppressed proliferation following high-dose intravenous vitamin C exposure.
High-dose intravenous vitamin C also strengthens the immune system’s ability to attack cancer. It has been shown to:
Together, these actions amplify immune-mediated tumor destruction.
The review summarizes multiple Phase I/II trials where high-dose intravenous vitamin C strengthened standard therapy:
Across all studies, safety and tolerability were excellent.
The review identifies the dosing regimen required to achieve tumor-selective, cytotoxic plasma levels:
75–100 grams IV per infusion, or >1.0 g/kg IV per infusion
Given 2–3 times per week for 6–8 cycles.
This reliably produces ≥20 mM plasma concentrations — the range associated with selective cancer cell killing — while remaining well-tolerated.
The authors also emphasize that most patients in clinical trials never reached the maximum tolerated dose, suggesting the therapeutic ceiling is likely far higher than what past studies explored.
This paper makes something very clear: Pharmacologic intravenous vitamin C is a multi-mechanistic, tumor-selective anti-cancer therapy that has been under-dosed, under-studied, and consistently underestimated.
Given its safety profile, low cost, and robust mechanistic data, high-dose vitamin C urgently warrants modern Phase III trials with appropriate pharmacologic dosing regimens.
Epidemiologist and Foundation Administrator, McCullough Foundation
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