Vitamin C (ascorbic acid)
Vitamin C/Nutrient Depletion:
- GeneralGeneral: Serum vitamin C concentrations below 0.2mg/dL indicate a significant deficiency, according to secondary sources.
- Based on secondary sources, vitamin C deficiency may cause fatigue, personality changes, and a decline in psychomotor performance. Long-term vitamin C deficiency results in symptomatic scurvy, which is characterized by gingival swelling and bleeding; loosening of the teeth; hyperkeratosis; perifollicular hemorrhages; petechial hemorrhages in the viscera; and hemorrhages into the muscles of the arms, legs, and joints (97; 98; 99; 100). Severe scurvy may progress to neuritis, jaundice, fever, dyspnea, and death. In infants, vitamin C deficiency is initially manifested as listlessness, anorexia, irritability, and failure to thrive. Later symptoms result from hemorrhage and collagen deficiency, with seizures, shock, and death if left untreated.
- AntibioticsAntibiotics: In a systematic review, the effects of vitamin C were decreased by tetracycline antibiotics such as doxycycline (Vibramycin®), minocycline (Minocin®), or tetracycline (Sumycin®) (21).
- AspirinAspirin: In humans on a low-ascorbic acid-intake diet, administration of acetylsalicylic acid increased urinary ascorbic acid, but at high ascorbic acid intake, acetylsalicylic acid decreased urinary ascorbic acid (63).
- AsthmaAsthma: Based on a systematic review and meta-analysis, lower dietary intakes and serum levels of vitamin C have been associated with an increased risk of asthma (101). This result has been disputed by another meta-analysis, in which such a relationship could not be determined (102).
- DiureticsDiuretics: In individuals with chronic renal failure, a 20mg intravenous dose of furosemide (Lasix) increased urinary losses of vitamin C (69).
- NicardipineNicardipine: In vitro, dihydropyridine calcium channel blockers inhibited ascorbic acid accumulation in human intestinal Caco-2 cells (74).
- NicotineNicotine: Nicotine products, such as cigarettes, cigars, chewing tobacco, and nicotine patches, may decrease the effects of vitamin C (76).
- PhytoestrogensPhytoestrogens: Oral estrogens may decrease the effects of vitamin C in the body (29)
- Pre-eclampsiaPre-eclampsia: Based on a systematic review, pre-eclampsia is associated with a reduction in antioxidant concentrations, including vitamin C (103).
- Proton pump inhibitors (PPIs)Proton pump inhibitors (PPIs): In healthy volunteers, omeprazole 40mg daily for four weeks reduced plasma vitamin C levels (77).
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The information in this monograph is intended for informational purposes only, and is meant to help users better understand health concerns. Information is based on review of scientific research data, historical practice patterns, and clinical experience. This information should not be interpreted as specific medical advice. Users should consult with a qualified healthcare provider for specific questions regarding therapies, diagnosis and/or health conditions, prior to making therapeutic decisions.