BACKGROUND: Inverse associations between micronutrient intake and cardiovascular 
outcomes have been previously shown, but did not focus on diabetic patients.
OBJECTIVE: To systematically review the role of micronutrients in the 
development/presence of cardiovascular outcomes in patients with diabetes.
METHODS: We searched Medline, Embase, and Scopus (January/1949-March/2012) for 
observational studies that evaluated micronutrients and cardiovascular outcomes 
in patients with diabetes, and then selected and extracted the data (two 
independent reviewers).
RESULTS: From the 15 658 studies identified, five were included, comprising 
three case-control and two cohorts, with a follow-up of 7-15 years. A 
meta-analysis was not performed due to the different antioxidant micronutrients 
(types and measurement methods) and outcomes evaluated. The micronutrients 
assessed were vitamin C intake in diet and/or supplementation, chromium and 
selenium in toenail samples, and α-tocopherol and zinc in serum levels. Intake 
of >300 mg of vitamin C through supplementation was associated with increased 
risk of cardiovascular disease, coronary artery disease (CAD), and stroke (RR 
1.69-2.37). High levels of α-tocopherol in serum were associated with 30% lower 
CAD risk in another study (HR 0.71; 95%CI 0.53-0.94). Among minerals (zinc, 
selenium, and chromium), an inverse association between zinc and CAD was 
observed; levels lower than 14.1 µmol/L were associated with an increased risk 
for CAD (RR 1.70; 95%CI 1.21-2.38).
CONCLUSION: The information available on this issue is scarce. Further 
prospective studies are needed to elucidate the role of these nutrients in the 
cardiovascular risk of patients with diabetes.