Vitamin C
Body function
Collagen synthesis; antioxidant protection; immune function; enhances iron absorption
Daily requirement
75 mg/day (women), 90 mg/day (men); smokers need an additional 35 mg/day
Deficiency signs
Fatigue, bleeding gums, slow wound healing, easy bruising, joint pain; severe deficiency causes scurvy
Excess risks
Diarrhoea and GI upset above 2000 mg/day; may increase kidney stone risk in susceptible individuals
At-risk groups
Smokers, people with limited fruit and vegetable intake, those with malabsorption conditions
Supplement forms
Ascorbic acid, sodium ascorbate (buffered), liposomal vitamin C
Food sources
- Spinach (cooked) — ~18 mg vitamin C per cup cooked
- Ginkgo nuts — ~15 mg per 30g
- Chestnuts — ~7 mg per 30g (unusually high for a nut)
- Avocado — ~10 mg per 100g
- Onion — ~6 mg per 80g (half an onion)
- Garlic — ~2.5 mg per 9g
- Mint leaf — ~3 mg per 10g
- Thyme leaf — ~4 mg per 3g fresh
- Basil leaf — ~2 mg per 10g
- Potatoes — ~20 mg per medium potato (with skin)
- Sweet potatoes — ~22 mg per medium
- Corn — ~10 mg per cup
- Purple sweet potatoes — ~20 mg per medium
- Kimchi — ~10 mg per 50g
- Cassava — ~20 mg per 100g cooked
- Sauerkraut — ~7 mg per 50g
- Yam — ~12 mg per 100g cooked
Related symptoms
Educational information only — not medical advice. This content does not diagnose, treat, or replace consultation with a qualified healthcare professional. Always seek professional medical advice for symptoms, supplement use, or health concerns.