Vitamin C (Ascorbic Acid)
What is Vitamin C (Ascorbic Acid)? A water-soluble antioxidant vitamin that is essential for: immune function, collagen production, iron absorption, wound healing and tissue repair. Unlike most animals, humans can’t make vitamin C, so we must regularly get it from food.
Function | Role of Vitamin C |
|
Immune Support | Enhances white blood cell function, protects against infection | |
Collagen Synthesis | Essential for skin, blood vessels, tendons, ligaments | |
Iron Absorption | Converts plant-based iron into a more absorbable form | |
Antioxidant Activity | Neutralizes free radicals, protects against oxidative stress | |
Brain Health | Supports neurotransmitter function and mood regulation | |
Too Little Vitamin C:
- Scurvy – fatigue, bleeding gums, poor wound healing, easy bruising, joint pain
- Frequent infections – due to weakened immune defense
- Iron-deficiency anemia- poor iron absorption in low vitamin C diets
Groups at Risk of Deficiency:
- Smokers
- People with limited fresh produce intake
- Alcoholism
- Restrictive diets
Too Much Vitamin C:
- No toxicity from food sources alone
- Diarrhea, nausea – common at doses > 2000 mg/day
- Kidney stones – rare but possible in predisposed individuals
Just Right (adults):
- Recommended 75-90 milligrams/day
- Smokers and those exposed to second-hand smoke: 110-125 mg/day
Medication Interactions
(consult your doctor)
- Chemotherapy and Radiation
- Statins
Food Sources
Plant
- Strawberries
- Citrus Fruits
- Bell Peppers (especially red) – more vitamin C than oranges
- Broccoli
- Kiwi – one of the highest vitamin C fruits per gram
- Tomatoes
- Papaya, Mango
- Leafy Greens (spinach, kale)
- Fresh herbs (parsley, thyme)
Cooking tips:
Vitamin C is the most fragile of vitamins, being heat, light and water sensitive. Preserve it by:
- Eating produce raw or lightly steamed
- Use quick stir-fry, roasting or blanching
- Store cut fruits and vegetables in airtight containers, avoiding soaking
- Levels of vitamin C may decrease with prolonged food storage
Reference: Vitamin C – Health Professional Fact Sheet