Vitamin C is not associated with coronary heart disease risk once life course socioeconomic position is taken into account: prospective findings from the British women's heart and health study

The reason why prospective cohort studies have found that plasma vitamin C concentration, or dietary intake of vitamin C, is protective against coronary heart disease (CHD) risk1 but randomised controlled trials have found no effect of vitamin C on CHD2 is unclear. We have previously suggested that this difference is caused by confounding.3 Our hypothesis is that high adult concentrations of vitamin C reflect a number of characteristics, including advantageous socioeconomic circumstances in childhood and adulthood, and that it is these characteristics, not vitamin C, that protect against CHD. The aim of this study is to examine whether the association between plasma vitamin C and CHD is confounded by life course socioeconomic position. METHODS Data from the British Women’s Heart and Health Study were used. Full details of the selection of participants and measurements used in the study have been previously reported.4 Between 1999 and 2001, 4286 British women aged 60–79 . . . [