Vitamin C has a checkered history in the context of being an effective agent for cancer therapy.
If a new study from researchers at the University of Iowa is to be believed, the administration method is crucial and determines how high dosage of vitamin C can be instrumental in killing cancer cells.
Generally, vitamin C therapies require oral ingestion of the vitamin by the affected patient. However, the latest study discloses that when a patient is given vitamin C intravenously, it is more effective. Why? The blood levels tend to be 100 to 500 times higher when compared with oral intake.
The researchers reveal that this high concentration in the blood is critical to the vitamin C's ability to fight off cancer.
Previous studies such as those by Garry Buettner, published in the journal Redox Biology, in December 2016, have suggested that at such high levels — which are in the millimolar range — while vitamin C is able to destroy the cancer cells, it does not cause any damage to normal cells.
Many clinics and hospitals are now testing the theory and a few clinical trials for lung and pancreatic cancer are being conducted in the process. These tests would combine regular radiation or chemotherapy with high dosages of intravenous vitamin C or "ascorbate" to see if it effectively destroys cancer cells.
The trials that were conducted during Phase 1 indicated that the treatment is harmless and the therapy is effective in improving patient results. The current trials have the objective of determining whether this treatment tends to improve survival.
The possibility of vitamin C breaking down easily has been raised in several quarters and, therefore, it ends up creating hydrogen peroxide — referred to as the reactive oxygen on many occasions. It also ends up damaging the DNA and tissues.
However, regular cells have plenty of methods to eradicate hydrogen peroxide on their own and, therefore, keeping this to low levels does not result in any damage.
The research reveals that "catalase" — an enzyme — is instrumental in removing the hydrogen peroxide, which disintegrating vitamin C creates. The researchers found that cells which have lower catalase activity had a higher probability of being vulnerable to damage and destruction when these were exposed to large vitamin C amounts.
This is an important discovery and could aid in the determination of which therapies and cancers can be addressed by using a high dosage of vitamin C during the treatment, according to Buettner
"Our results suggest that cancers with low levels of catalase are likely to be the most responsive to high-dose vitamin C therapy, whereas cancers with relatively high levels of catalase may be the least responsive," he notes.
The number of people living beyond a cancer diagnosis in the United States was reportedly 14.5 million in 2014 and this figure is expected to rise to about 19 million in 2024.
The long-term goal of the ongoing research is to develop methods that can measure the catalase levels in tumors.