Comparison of the antioxidant capacity of coffee roasts and their effects on cardiovascular risk factors in healthy subjects

Author(s)

Telma Angelina Faraldo Corrêa

• Document type: Doctoral Thesis
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Faculdade de Saúde Pública (FSP/CIR)
• Defense date: 2012-09-12

Examining board members

Elizabeth Aparecida Ferraz da Silva Torres; Liania Alves Luzia; Gláucia Maria Pastore; Maria Therezinha Serrão Peraçoli; Sandra Roberta Gouvea Ferreira Vivolo

• Advisor: Elizabeth Aparecida Ferraz da Silva Torres; Luiz Antonio Machado Cesar

Abstract

Introduction: Coffee is rich in bioactive substances and it is among the major contributors to the total antioxidant ingestion in several countries. The roasting degree of coffee is important for its antioxidant activity. Studies indicate that the moderate consumption of filtered coffee is involved in the prevention of chronic diseases, which are usually associated and constitute serious problems of public health. However, literature does not present consensus about the beneficial effects of coffee in the prevention of these diseases. Objectives: To compare the antioxidant activity of the two coffee roasts (medium light and medium roast) and their effects on biomarkers of the cardiovascular risk in healthy volunteers. Methods: The antioxidant characterization of the coffee beverages was performed by the total phenolic content analysis, phenolic profile, caffeine, melanoidins and total antioxidant capacity - TAC (DPPH radical scavenging capacity and Oxygen radical absorbance capacity - ORAC assays). After 1-week washout, twenty healthy volunteers (20 to 65 years old) consumed medium light roast or medium roast paperfiltered coffee for 4 weeks and then switched to the other roast for an additional 4 weeks in a randomized crossover trial that lasted 9 weeks. Plasma lipids, lipoprotein (a), total homocysteine, serum glycemic biomarkers, and twenty-four hours blood pressure were measured at baseline and after each intervention. Levels of total antioxidant status (TAS) and ORAC were evaluated in plasma, and antioxidant enzymes activities (superoxide dismutase - SOD, glutathione peroxidase - GPx and catalase - CAT) in erythrocytes. Lipid peroxidation inhibition capacity was determined in plasma by oxidized LDL and 8-isoprostane assays. Endothelial dysfunction-related inflammation biomarkers were measured in plasma by immunoassays. Results: Twenty healthy volunteers (49.5 + 8.9 years) were evaluated. Medium light roast coffee showed higher chlorogenic acids (334 mg/150 mL; p < 0.001) and less caffeine (231 mg/150 mL; p = 0.003) than medium roasting (210 mg/150 mL and 244 mg/150 mL, respectively). Melanoidins were significant higher in medium roast than medium light roast (p < 0.001). There was an increase in the Castelli indexes after medium light roast consumption (5 per cent in the index I; p = 0.01, and 6 per cent in the index II; p = 0.03). No significant differences were observed for TAC between the medium light roast and medium roast. Both roasts increased plasma total cholesterol and LDL concentrations (10 per cent , and 12 per cent for medium light roast; 12 per cent , and 14 per cent for medium roast, respectively) (p < 0.05). Medium roast also increased HDL concentration by 7 per cent (p = 0.003). Compared with baseline, subjects had an increase of 21 per cent and 26 per cent in TAS, 13 per cent and 13 per cent in CAT, 52 per cent and 75 per cent in SOD, and 62 per cent and 49 per cent in GPx after medium light and medium roast consumption (p < 0.001), respectively. Both roasts increased soluble vascular cell adhesion molecule-1 (sVCAM-1) concentrations (18 per cent for medium light roast and 14 per cent for medium roast) (p < 0.05). Plasma fibrinogen concentration increased 8 per cent after medium roast intake (p = 0.01), and soluble E-selectin (sE-selectin) increased 12 per cent after medium light roast intake (p = 0.02). Although coffee beverages have increased total cholesterol and LDL levels, they were not related to elevation in total homocysteine, lipoprotein (a), and biomarkers of diabetes and lipid peroxidation. Conclusion: Moderate paper-filtered coffee consumption may have some undesirable impact on cardiovascular risk in healthy subjects regardless of its antioxidant content. (AU)

• FAPESP's process: 08/10933-6 - STUDY OF ANTIOXIDANT ACTION AND THE BIOACTIVE COMPOUNDS EFFECTS OF COFFEE IN THE PREVENTION OF CHRONIC DISEASES NOT TRANSMISSIBLE: DYSLIPIDEMIA, DIABETES MELLITUS TYPE 2 AND ARTERIAL HYPERTENSION
• Grantee: Telma Angelina Faraldo Corrêa
• Support Opportunities: Scholarships in Brazil - Doctorate