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

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.

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Dec. 15, 2023 See more Expert Answers

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  26. Cancer survivorship program
  27. Cancer treatment
  28. Cancer treatment myths
  29. Cancer-related fatigue
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  31. Cancer-related weakness
  32. CAR-T cell therapy
  33. Chemo targets
  34. Chemoembolization
  35. Chemotherapy
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  38. Chemotherapy nausea and vomiting: Prevention is best defense
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  40. Complete blood count (CBC)
  41. Cough
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  43. Curcumin: Can it slow cancer growth?
  44. Cancer-related diarrhea
  45. Doppler ultrasound: What is it used for?
  46. Dysphagia
  47. Eating during cancer treatment: Tips to make food tastier
  48. Fatigue
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  51. Honey: An effective cough remedy?
  52. Hyperthermic isolated limb perfusion
  53. Immunotherapy
  54. Infographic: CAR-T Cell Therapy
  55. Intensity-modulated radiation therapy (IMRT)
  56. Intrathecal chemotherapy
  57. Isolated limb infusion
  58. Joint pain
  59. Laryngitis
  60. Low blood counts
  61. Magic mouthwash
  62. Medical marijuana
  63. Microwave ablation for cancer
  64. Mindfulness exercises
  65. Minimally invasive cancer surgery
  66. Monoclonal antibody drugs
  67. Mort Crim and Cancer
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  69. MRI
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  72. Night sweats
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  74. Palliative care
  75. PALS (Pets Are Loving Support)
  76. Pelvic exenteration
  77. PET/MRI scan
  78. Precision medicine for cancer
  79. Proton beam therapy
  80. Proton therapy
  81. Radiation therapy
  82. Regional perfusion therapy
  83. Seeing inside the heart with MRI
  84. Self-Image During Cancer
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  86. Shortness of breath
  87. Sisters' Bone Marrow Transplant
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  90. Stem cells: What they are and what they do
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  96. TVEC (Talimogene laherparepvec) injection
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