**3. Vitamin dosage in disease conditions**

Several disease conditions worsen vitamin C deficiency especially among hospitalized patients [28–30]. Critically ill patients required higher doses (at least 2–3 g/day) of vitamin C supplementation to restore their normal plasma levels [31, 32]. Much higher doses improved outcome in burn patients administered infusions at 60 mg/kg/hour within the first day of admission [33]. Higher doses of vitamin C administration could be lifesaving in patients with severe illnesses such as sepsis as reviewed by [34].

The **Table 1** below summarizes the different doses of vitamin C in some controlled trials. Most of the earlier trials used an average dose of 500 mg/day, but the recent trials are now utilizing much higher doses.


*AREDS: Age-Related Eye Disease Study Research Group; BP: blood pressure; CV: cardiovascular; CVD: cardiovascular disease; HAART: highly active antiretroviral therapy; RCCT: randomized double-blind controlled clinical trial; US: United States of America.*

### **Table 1.**

*Outcomes of vitamin C supplementation at different doses in some studies.*
