High Dose Vitamin C's role in cancer treatment
Recently there has been a lot of talk about high dose vitamin C and it’s use in cancer treatment. Let’s take a look at the role vitamin C plays in our daily lives, what we know about vitamin C and cancer treatment and what we don’t know about the role of vitamin C in cancer treatment.
What is Vitamin C?
Vitamin C is an essential nutrient found in food and dietary supplements that cannot be made by humans. Vitamin C is an antioxidant and helps prevent damage to cells caused by free radicals. Vitamin C has multiple essential functions within the body, including integral roles in various anti-cancer mechanisms. Intake of vitamin C, through the consumption of vegetables and fruit may play an important role in the defense against cancer.
High dose vitamin C can be given by intravenous infusion or be taken by mouth but much higher blood levels of vitamin C can be achieved through IV infusion (up to 100x ). At this time there is little evidence that high dose vitamin C by itself is an effective treatment for cancer nor is it an effective measure for cancer prevention.
What we know about Vitamin C and cancer treatments
Numerous studies have been performed using high dose vitamin C with conventional cancer treatments to see if there was improvement in the outcome of the cancer treatment including shrinkage of the tumor and improved life expectancy. Most of these studies are very small with inconsistent dosages of vitamin C . The results of these trials have been very mixed with most showing little if any benefit from adding vitamin C to conventional chemotherapy as far as improving overall life expectancy.
Intravenous vitamin C appears to be well tolerated with side effects occurring in less than 1% of patients. Most side effects are minor and include lethargy, fatigue, change in mental status and vein irritation.
Studies consistently show that cancer patients have lower levels of circulating vitamin C than healthy volunteers. This is probably secondary to increased turnover of vitamin C as a result of the inflammatory aspects of cancer as well as decreased intake of vitamin C. Both pre-clinical and clinical studies indicate that intravenous vitamin C can decrease chemotherapy-induced side effects such as fatigue, weight loss and general quality of life, likely through its antioxidant and anti-inflammatory activities.
What is the bottom line?
The bottom line is that high dose intravenous vitamin C has no role in primary cancer treatment and that its use with conventional cancer therapy should only be given as part of a well designed clinical trial. There is no evidence that high dose vitamin C has a role in cancer prevention. Cancer prevention is best achieved through healthy lifestyle habits including consumption of 7-9 servings of fresh vegetables and 2 servings of fruit per day, abstaining from tobacco products, managing stress, daily exercise and movement, 7-9 hours of quality sleep per day and having loving, supportive social relationships. There may be a role for the use of high dose vitamin C for the treatment of chemotherapy-induced side effects including fatigue, weight loss and general quality of life.