Vitamin C can alter inflammatory processes

The study included 109 patients from Denmark and the USA. All of them were diagnosed with either a precancerous blood syndrome — a condition that can develop into a malignant disease — or a low‑risk form of blood cancer. The participants were randomly divided into two groups: 55 people received oral vitamin C at a dose of 1,000 mg per day, and 54 received a placebo. The treatment lasted 12 months.

The researchers chose the growth rate of precancerous or cancerous cells as the main criterion for effectiveness. According to this indicator, there was no significant difference between the groups. However, vitamin C affected other important processes. In patients who took the supplement, signaling pathways related to inflammation changed, and these changes corresponded to a more favorable prognosis. In addition, they were less likely to experience anemia, pneumonia, acute aseptic arthritis, and internal bleeding. However, problems with the gastrointestinal tract were observed more frequently.

The most noticeable, albeit preliminary, result concerned survival. During the median observation period of nearly three and a half years (33.6 months), 35 deaths were recorded: 24 in the placebo group and 11 in the vitamin C group. Nevertheless, it is too early to draw final conclusions. A larger‑scale phase III study is needed to confirm the effect.

According to one of the lead authors of the study, Peter Jones from the Van Andel Institute, the results provide a strong basis for continuing to study whether and how vitamin C can benefit people with precancerous or early forms of blood disorders. Although further research is still ahead, experts are cautiously optimistic about the possibility that this data will help develop strategies in the future to prevent the development of leukemia.

His colleague Kirsten Grenbeck from Rigshospitalet in Copenhagen adds: the results are encouraging, especially considering what they may mean for patients with early stages of blood diseases. But it is still too early to make clinical recommendations based on the data obtained. Researchers hope that a larger study will provide definitive answers.

It is important to understand that this is not about preventive vitamin C intake by healthy people, but about a specific context: patients with already diagnosed precancerous conditions. A dose of 1,000 mg per day exceeds the usual nutritional requirement and was administered under medical supervision as part of a clinical trial. You should not self‑prescribe such dosages.