Introduction: A recent research experiment identified that maladapted (CMS+) highlanders exhibit elevated systemic biomarkers of oxidative-nitrosative stress and impaired vascular structure-function (relative to well-adapted controls; CMS-)1. This may be due to the depletion in ascorbate given that it is the primary water soluble chain-breaking antioxidant in the circulation. This may be the outcome of inadequate dietary intake, hence the focus of the present study. Methods: Thirty-six male highlanders with CMS (n = 22, CMS+; age 57 ± 10) and without CMS (n = 14, CMS-; age 52 ± 12) participated in the study. Participants were interviewed to collect a 24 hour structured dietary recall using a portion size photo atlas2. The stages followed in the UK Low Income Diet and Nutrition survey were used3. The dietary questionnaires were analysed using NetWISP dietary analysis software (Version 4.0, Tinuviel Software; Anglesey, UK). Data were tested for normality using Shapiro-W-Wilks tests. Kruskal-Wallis and Mann-Whitney tests to compare the groups were performed. Significance level was established at P < 0.05 and data are expressed as mean ± standard deviation (SD). Results: Consumption of ascorbate (Vitamin C) is clearly deficient in the maladapted male highlanders (CMS+, 47 ± 35) versus the well-adapted controls (CMS-, 66 ± 33). The intake demonstrates the (borderline) significant differences between the two groups (P < 0.07); though consumption is below the recommendations (table). Conclusions: These findings are the first that describe antioxidant intake in the population affected by Monge’s disease (CMS+). Furthermore, the result supports our hypothesis that compared to controls (Bolivian non-diseased native highlanders), CMS patients are characterised by an inadequate intake of dietary antioxidants. This is an independent variable that has previously been associated with augmented oxidative-nitrosative stress and vascular endothelial dysfunction subsequent to impaired antioxidant defence.