Vitamin C Tied to Better Survival in Early Blood Cancers

A surprisingly simple molecule, vitamin C, is drawing new attention not for scurvy prevention but for a possible role in slowing the tide of early blood cancers. The signal comes from a randomized clinical study that hints supplements might improve survival in people with precancerous or low-risk blood disorders. The catch: the finding emerged in an exploratory analysis and demands larger trials.

What the EVITA trial actually tested

The phase 2 EVITA study enrolled 109 participants in Denmark and the United States. Researchers randomly assigned 55 people to take 1,000 milligrams of oral vitamin C daily and 54 to take a matching placebo for 12 months. The trial was double-blind, so neither patients nor investigators knew who received active supplement versus placebo. That design reduces bias and strengthens any observed differences.

After a median follow-up of 33.6 months, investigators recorded 35 deaths. Twenty-four occurred in the placebo arm and 11 in the vitamin C arm. Those numbers were tallied using an intention-to-treat approach, meaning participants were analyzed according to their original assignment regardless of adherence. That preserves the benefits of randomization but does not prove causation by itself.

Despite the mortality difference, the study’s primary endpoint—measures of abnormal cell growth typical for these disorders—did not differ appreciably between groups. In other words, vitamin C did not change the trial’s main laboratory measure, yet clinical outcomes diverged in a way that caught researchers’ attention. Safety signals were mixed: several complications such as anemia, pneumonia, internal bleeding, and acute aseptic arthritis were less frequent among those taking vitamin C, but gastrointestinal side effects were reported more often in the supplement group.

Why scientists thought to try vitamin C

Vitamin C does more than support the immune system. At the cellular level it acts as a cofactor for a family of proteins called TET enzymes. TETs help regulate DNA methylation, a chemical mark that controls whether genes are turned on or turned off. Loss of TET function is a common feature in a range of blood disorders and early-stage leukemias. Laboratory data show that vitamin C can enhance TET activity, restoring aspects of normal gene regulation in blood cells.

That biochemical logic drove the EVITA investigators to test whether oral vitamin C might alter disease biology in people at risk of progression to leukemia or already living with low-risk blood cancers. The trial was led by the Van Andel Institute–Stand Up To Cancer Epigenetics Dream Team, with co-senior authors Kirsten Grønbæk, MD, PhD, of Rigshospitalet, Copenhagen University Hospital, and Peter A. Jones, PhD, of Van Andel Institute.

“We are encouraged by our findings and what they ultimately could mean for people with these early-stage blood disorders,” Grønbæk said. “Although it is too soon to make recommendations based on our results, we are hopeful that a larger study will give us more definitive answers.” Jones added that the trial provides a strong rationale to continue exploring whether vitamin C can help intercept leukemia development.

Implications and next steps

So what should clinicians and patients take away? Not yet anything definitive. The mortality difference is intriguing but exploratory. Phase 2 trials are not powered to settle survival questions; they are meant to test safety, feasibility, and biological signals that justify a larger phase 3 effort. A well-designed phase 3 trial would need more participants, longer follow-up, and prespecified survival endpoints to confirm whether vitamin C truly confers a survival advantage.

There are practical advantages to studying vitamin C. It is inexpensive, widely available, and generally well tolerated at moderate doses. But ‘‘well tolerated’’ does not mean harmless; higher oral doses can cause gastrointestinal upset and, in rare situations, complications for people with certain metabolic problems. Any recommendation to take supplements should await confirmatory evidence and clinician guidance.

Expert Insight

“The EVITA results are the kind of early clinical signal that sparks both excitement and caution,” said Dr. Elena Morales, a hematologist and clinical trialist not involved with the study. “Mechanistically, the TET-vitamin C connection is convincing in the lab. Translating that into a real, reproducible benefit for patients is the crucial next step. We need robust phase 3 data before changing practice, but this is a promising direction for chemoprevention in hematology.”

Conclusion

EVITA offers a provocative hint that a common nutrient might influence survival in certain early-stage blood disorders by acting on gene-regulating enzymes and inflammatory pathways. The primary laboratory endpoints did not shift, yet clinical outcomes did—an ambiguity that only larger, definitive trials can resolve. For now, vitamin C remains a candidate for further study rather than a new standard of care.