Some links from the show:

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• Vitamin A and night visions
  
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  • British Journal of Opthalmology: Night vision in a case of vitamin A deficiency due to malabsorption
    
  
  
  
• Types of vitamin A
  
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  • National Institutes of Health: Vitamin A
    
  
  
  
• Overdosing on vitamin A
  
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  • Wikipedia: Hypervitaminosis A
    
  
  
  
• How vegans get B12
  
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  • PETA: Vegan B12 sources that will make you healthy in body and mind
    
  
  
  
• Linus Pauling's vitamin C quest
  
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  • Vox: How Linus Pauling duped America into believing vitamin C cures colds
    
  
  
  
• Does vitamin C treat colds?
  
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  • Cochrane Library: Vitamin C for preventing and treating the common cold
    
  • WebMD: Vitamin C for the common cold