C-reactive protein (CRP) is a blood marker commonly used to indicate the presence of inflammation in the body. Elevated CRP levels have been linked with cardiovascular disease and a range of other chronic health concerns.
A study published in the American Journal of Epidemiology (2009; 170(4):464–471) examined the relationship between vitamin C status and CRP levels in healthy, non-smoking adults between the ages of 20 and 29. Vitamin C intake was assessed using dietary questionnaires, while serum ascorbic acid levels were measured from overnight fasting blood samples using liquid chromatography.
The researchers found that vitamin C insufficiency was common in this young population: 33% of participants had suboptimal vitamin C levels, and 14% met criteria for vitamin C deficiency. Individuals with lower serum vitamin C levels tended to have higher CRP concentrations, indicating greater underlying inflammation.
Vitamin C deficiency was also associated with higher body mass index (BMI), increased blood pressure, and larger waist circumference. Not surprisingly, participants who reported lower vitamin C intake on dietary questionnaires also showed lower measured serum ascorbic acid levels.
These findings suggest that vitamin C status may be linked to inflammatory markers and cardiometabolic risk factors even in young, otherwise healthy adults. More broadly, the study reinforces the idea that dietary patterns can influence biological markers associated with long-term health risk.
