Comparison of antioxidant efficacy of vitamin E, vitamin C, vitamin A and fruits in coronary heart disease: a controlled trial.

ABSTRACT

OBJECTIVE: To determine the efficacy of various antioxidant vitamins and a major dietary source of antioxidants (fruits) we performed a randomized controlled trial. METHODS: 175 successive patients with coronary heart disease (CHD) presenting to our centre were recruited and using a Latin-square design divided into five groups of 35 each. The groups were matched for age, lifestyle and dietary variables, clinical diagnosis and drug treatment status. None of the patients was on lipid-lowering drugs. Supplemental vitamins were stopped for one month before study began and American Heart Association Step II dietary advice was given to all. At baseline, total cholesterol, triglycerides, HDL and LDL cholesterol and lipid peroxide measured as thiobarbaturic acid reactive substances (TBARS) were determined. Group I received placebo capsules; Group II vitamin E 400 units/day; Group III vitamin C 1,000 mg; Group IV vitamin A 25,000 IU; Group V received 400 gm of fruit daily. Lipids and lipid peroxide levels were determined at 30 days follow-up. RESULTS: Response rate in various groups varied form 86% to 91%. No significant changes in total, HDL, LDL cholesterol and triglyceride levels were seen in Groups I, II, III and IV (paired t-test p > 0.05). In Group V there was a significant decrease in total cholesterol (-7.8 +/- 11.1%), and LDL cholesterol (-11.2 +/- 25.4%) and increase in HDL cholesterol (+12.9 +/- 20.1%) (paired t-test p < 0.01). Lipid peroxide levels decreased significantly in all the treatment groups (p < 0.01). This decrease was the highest in Group II (vitamin E; -36.4 +/- 17.7%) as compared to Group III (vitamin C -19.8 -/+ 10.8%); Group IV (vitamin A -5.4 +/- 17%) and Group V (fruits -13.1 +/- 12.0%). CONCLUSIONS: All the antioxidant vitamins and fruits significantly decrease lipid peroxide levels and oxidant load in CHD patients. However, fruits are the best choice as they also favourably modify the lipid profile.