August 2021    
         
         
 
     
  Vitamin D’s day in the sun  
     
  The topic of vitamins and supplements is fraught, tied up with commercialism, the anti-vax movement, and diet culture. A “couldn’t hurt, might help” mindset is especially dangerous: some interfere with medication, and high doses can be toxic.  
     
  There’s little evidence that daily vitamins or supplements—treated as food rather than medicine by the FDA—provide health benefits, unless you have a deficiency.  
     
 
  A variety of real food is the best way to get vital vitamins.  
 
       
  An estimated 40 percent of Americans, however, are vitamin D deficient, especially those with darker skin since melanin interferes with the vitamin’s production. And a 2017 study concluded that vitamin D helped prevent acute respiratory tract infections, making the vitamin of special interest when COVID-19 emerged.  
     
  The D debate  
     
 
vitamin D food and pills
 
 
     
  (iStock.com/microgen)  
     
 
     
  Does vitamin D play a role in COVID-19 prevention or treatment?  
     
  A 2020 UChicago study found that patients with vitamin D deficiency were almost twice as likely to test positive for SARS-CoV-2. Then research published this past March found that Black patients with elevated levels of vitamin D had even less risk of contracting COVID-19 than those with sufficient levels.  
     
  But these are observational studies and, as the adage goes, correlation does not equal causation. The jury is still out on the value of vitamin D in fighting the pandemic.  
     
 
 
  Deficient evidence  
     
 
     
  1  
     
 
Vitamin D, skin color, and UV radiation damage all connect.
 
     
     
     
 
     
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Vitamin D deficiency is a risk factor for uterine fibroids—noncancerous tumors that affect up to 80 percent of premenopausal people—and is likely related to a higher fibroid prevalence in people of color.
 
     
     
     
 
     
  3  
     
 
Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, says most immune-boosting supplements do nothing, but he does recommend vitamins C and D.
 
     
     
 
         
         
    Spotlight    
         
         
 
     
  Dietary detriment  
     
 
cat and dog pals
 
 
     
  (iStock.com/chendongshan)  
     
 
     
  As vitamin D deficiency awareness has risen, so have accidental companion animal poisonings.  
     
  A stray Flintstones daily vitamin is less likely to cause an emergency, but the high-dose weekly supplements meant to combat severe deficiency pose a real threat. Like medicine, keep vitamins out of paws’ reach.  
     
     
     
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