Fifty million Americans have allergies, according to the Asthma and Allergy Foundation of America 3. Allergies are the result of histamine, a substance released when foreign particles invade the body and cause an immune response such as hives, sneezing and watery eyes. Vitamin C, a water-soluble vitamin your body excretes through the urine, acts as an antihistamine. Consult your physician before starting any new supplements to treat allergies, as adverse reactions can occur.

Vitamin C as an Antihistamine

Vitamin C reduces the amount of histamine in the blood. An article from the August 1992 “Journal of the American Dietetic Association” found that 2 g of ascorbic acid decreased histamine levels by 40 percent 45. An article from the April 1992 “Journal of the American College of Nutrition” also found that 2 g of ascorbic acid decreased histamine levels by 38 percent, and those levels did not change for four hours 4.

How Vitamin C Works as an Antihistamine

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In the March 2011 “Journal of Evidence-Based Complementary & Alternative Medicine,” researchers reported that Vitamin C works as an antihistamine by destroying the molecular structure of the imidole ring of the histamine molecule, thereby decreasing the amount of histamine in the blood 6. The absorption of vitamin C is highly dependent on the amount ingested. To achieve tissue saturation of vitamin C requires more than 500 mg per day. More than 2 g can cause diarrhea.

Vitamin C Deficiency

Although vitamin C toxicity is rare, since it is a water-soluble vitamin and cannot be stored, the same cannot be said about vitamin C deficiency. In the May 2004 “American Journal of Public Health,” researchers assessed the occurrence of vitamin C deficiency in the U.S. among a population of 15,769 people aged 12 to 74 years, and found overall that 14 percent of males and 10 percent of females were vitamin C deficient. A deficiency in vitamin C can cause:

• scurvy
  
• easy bleeding
  
• anemia
  
• swollen joints
  
• dry skin
  
• weight gain
  
• dry hair

Foods High in Vitamin C

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Fruits and vegetables high in vitamin C include:

• oranges
  
• green peppers
  
• mangoes
  
• strawberries
  
• cantaloupe
  
• tomatoes
  
• broccoli
  
• cabbage
  
• blueberries
  
• raspberries
  
• fortified juices

To maximize vitamin C absorption, consume fruits and vegetables raw because vitamin C is sensitive to temperature, light and air.