I've heard that vitamin C might be an alternative cancer treatment. What can you tell me about it?

Answer From Karthik Giridhar, M.D.

Interest in using very high doses of vitamin C as a cancer treatment began as long ago as the 1970s when it was discovered that some properties of the vitamin may make it toxic to cancer cells. Initial studies in humans had promising results, but these studies were later found to be flawed.

Subsequent well-designed, randomized, controlled trials of vitamin C in pill form found no such benefits for people with cancer. Despite the lack of evidence, some alternative medicine practitioners continue to recommend high doses of vitamin C for cancer treatment.

More recently, vitamin C given through a vein (intravenously) has been found to have different effects than vitamin C taken in pill form. This has prompted renewed interest in the use of vitamin C as a cancer treatment.

There's still no evidence that vitamin C alone can cure cancer, but researchers are studying whether it might boost the effectiveness of other cancer treatments, such as chemotherapy and radiation therapy, or reduce treatment side effects.

There are still no large, controlled clinical trials that have shown a substantial effect of vitamin C on cancer, but some preliminary studies do suggest there may be a benefit to combining standard treatments with high-dose IV vitamin C. Until clinical trials are completed, it's premature to determine what role vitamin C may play in the treatment of cancer.

With

Karthik Giridhar, M.D.

Feb. 27, 2020 See more Expert Answers

See also

  1. Adjuvant therapy for cancer
  2. After a flood, are food and medicines safe to use?
  3. Alternative cancer treatments: 10 options to consider
  4. Atypical cells: Are they cancer?
  5. Biological therapy for cancer
  6. Biopsy procedures
  7. Blood Basics
  8. Bone marrow transplant
  9. Bone scan
  10. Cancer
  11. Cancer blood tests
  12. Myths about cancer causes
  13. Infographic: Cancer Clinical Trials Offer Many Benefits
  14. Cancer diagnosis: 11 tips for coping
  15. Cancer diagnosis? Advice for dealing with what comes next
  16. Cancer-related fatigue
  17. Cancer pain: Relief is possible
  18. Cancer-prevention strategies
  19. Cancer risk: What the numbers mean
  20. Cancer surgery
  21. Cancer survival rate
  22. Cancer survivors: Care for your body after treatment
  23. Cancer survivors: Late effects of cancer treatment
  24. Cancer survivors: Managing your emotions after cancer treatment
  25. Cancer survivors: Reconnecting with loved ones after treatment
  26. Cancer treatment decisions: 5 steps to help you decide
  27. Cancer treatment for men: Possible sexual side effects
  28. Cancer treatment for women: Possible sexual side effects
  29. Cancer treatment myths
  30. Cancer Vaccine Research
  31. Cellphones and cancer
  32. Chemo Targets
  33. Chemoembolization
  34. Chemotherapy
  35. Chemotherapy and hair loss: What to expect during treatment
  36. Chemotherapy and sex: Is sexual activity OK during treatment?
  37. Chemotherapy nausea and vomiting: Prevention is best defense
  38. Chemotherapy side effects: A cause of heart disease?
  39. Complete blood count (CBC)
  40. Cough
  41. CT scan
  42. CT scans: Are they safe?
  43. Curcumin: Can it slow cancer growth?
  44. Cancer-related diarrhea
  45. Eating during cancer treatment: Tips to make food tastier
  46. Fatigue
  47. Fertility preservation
  48. Get ready for possible side effects of chemotherapy
  49. Ginger for nausea: Does it work?
  50. How plant-based food helps fight cancer
  51. Intrathecal chemotherapy
  52. Joint pain
  53. Joint pain: Rheumatoid arthritis or parvovirus?
  54. Low blood counts
  55. Magic mouthwash
  56. Medical marijuana
  57. Mediterranean diet recipes
  58. Mindfulness exercises
  59. Monoclonal antibody drugs
  60. Mort Crim and Cancer
  61. Mouth sores caused by cancer treatment: How to cope
  62. MRI
  63. Muscle pain
  64. Night sweats
  65. No appetite? How to get nutrition during cancer treatment
  66. Palliative care
  67. Palliative care
  68. PALS (Pets Are Loving Support)
  69. Pelvic exenteration
  70. PET/MRI scan
  71. Pet therapy
  72. Radiation therapy
  73. Routine cancer screening during coronavirus (COVID-19) pandemic
  74. Infographic: Scalp Cooling Therapy for Cancer
  75. Secondhand smoke
  76. Seeing Inside the Heart with MRI
  77. Self-Image During Cancer
  78. Sentinel lymph node mapping
  79. Sisters' Bone Marrow Transplant
  80. Sleep tips
  81. Mediterranean diet
  82. Radiation simulation
  83. Small cell, large cell cancer: What this means
  84. Stem Cells 101
  85. Stem cells: What they are and what they do
  86. Thalidomide: Research advances in cancer and other conditions
  87. Treating pain: When is an opioid the right choice?
  88. Tumor vs. cyst: What's the difference?
  89. Ultrasound
  90. Unexplained weight loss
  91. Stem cell transplant
  92. How cancer spreads
  93. MRI
  94. PICC line placement
  95. Compassionate use
  96. When cancer returns: How to cope with cancer recurrence
  97. X-ray
  98. Your secret weapon during cancer treatment? Exercise!