Inflammation is a biological response triggered by the immune system in response to a physical injury or infection. Vitamin C’s immune-boosting and antioxidant properties can mediate the body’s inflammatory response, reducing the symptoms or risk of various diseases. Evidence suggests that vitamin C can lower C-reactive protein, a marker of inflammation.

C-reactive protein (CRP) is a protein that increases in the blood with inflammation and infection as well as following a heart attack, surgery, or trauma. It is one of several proteins that are often referred to as acute phase reactants. Blood levels of CRP greater than 1 milligram per liter are indicative of elevated cardiovascular disease risk.

The randomized study involved nearly 400 healthy adults (average age, 44 years) who took 1 gram of vitamin C, 800 international units of vitamin E, or a placebo every day for two months. The findings revealed that vitamin E had no effect on lowering CRP; however, vitamin C supplementation decreased CRP 16.7 percent compared to pre-treatment measurements, but only in participants who had baseline CRP levels above 1 milligram per liter. This reduction in CRP was comparable to those achieved with statins (cholesterol-lowering drugs).

Interestingly, the study identified a strong link between obesity and elevated CRP levels. Whereas 25 percent of normal-weight people had elevated CRP levels of CRP, 50 percent of overweight participants and 75 percent of obese participants had elevated levels.

These findings suggest that vitamin C might be able to decrease inflammation to a similar magnitude as some statins in people at a higher risk of cardiovascular disease based on CRP levels.

• Link to study abstract.