The U.S. researchers at the University of California, Berkeley said that vitamin C supplements can lower concentrations of C-reactive protein (CRP), a biomarker of inflammation and powerful predictor of heart disease and diabetes.

The same study though has found no benefits of daily doses of vitamin E. and the researchers said one reason could be that vitamin E is fat soluble and found in cell membranes, while vitamin C is water soluble and found in intercellular fluid.

Lead author Gladys Block, UC Berkeley professor emeritus of epidemiology and public health nutrition said, "This is an important distinction; treatment with vitamin C is ineffective in persons whose levels of C-reactive protein are less than 1 milligram per liter, but very effective for those with higher levels."

She said that for healthy, non-smoking adults with an increased level of C-reactive protein, a daily dose of vitamin C was seen to lower levels of the inflammation biomarker after two months compared with those who took a placebo. The effect seen was comparable to that in many other studies of statins, the cholesterol-lowering drugs, Block said.

The Brigham and Women's Hospital study noted that several larger statin trials lowered C-reactive protein levels by about 0.2 milligrams per liter; in this latest study, vitamin C lowered C-reactive protein by 0.25 milligrams per liter.

Published in the journal Free Radical Biology and Medicine, the study did not see any benefits for those who did not have elevated CRP levels to start with. "This is an important distinction; treatment with vitamin C is ineffective in persons whose levels of CRP are less than 1 milligram per liter, but very effective for those with higher levels. Grouping people with elevated CRP levels with those who have lower levels can mask the effects of vitamin C. Common sense suggests, and our study confirms, that biomarkers are only likely to be reduced if they are not already low," said Block.

The researchers said further studies were called for to establish vitamin C’s beneficial effect on CRP levels beyond the two month span of the study. "This is clearly a line of research worth pursuing. It has recently been suggested by some researchers that people with elevated CRP should be put on statins as a preventive measure. For people who have elevated CRP but not elevated LDL cholesterol, our data suggest that vitamin C should be investigated as an alternative to statins, or as something to be used to delay the time when statin use becomes necessary," said Block.