Intake of carbohydrates compared with intake of saturated fatty acids and risk of myocardial infarction: importance of the glycemic index

Marianne U Jakobsen; Claus Dethlefsen; Albert M Joensen; Jakob Stegger; Anne Tjønneland; Erik B Schmidt; Kim Overvad

doi:10.3945/ajcn.2009.29099

© 2010 American Society for Nutrition

Intake of carbohydrates compared with intake of saturated fatty acids and risk of myocardial infarction: importance of the glycemic index¹,²,³

¹From the Department of Clinical Epidemiology Aarhus University Hospital Aalborg Denmark (MUJ); the Department of Cardiology Center for Cardiovascular Research Aalborg Hospital Aarhus University Hospital Aalborg Denmark (MUJ CD AMJ JS EBSKO); the Danish Cancer Society Institute of Cancer Epidemiology Copenhagen Denmark (AT);the Department of Epidemiology School of Public Health Aarhus University Aarhus Denmark (KO).

↵2 This work is part of the project Hepatic and Adipose Tissue and Functions in the Metabolic Syndrome (HEPADIP; www.hepadip.org), which is supported by the European Commission as an Integrated Project under the 6th Framework Programme (contract LSHM-CT-2005-018734), and part of the research program of the Danish Obesity Research Centre (DanORC; www.danorc.dk), which is supported by the Danish Council for Strategic Research (contract 2101-06-0005).
↵3 Address correspondence to MU Jakobsen, Department of Clinical Epidemiology, Aarhus University Hospital, Sdr. Skovvej 15, DK-9000 Aalborg, Denmark. E-mail: muj{at}dce.au.dk.

Abstract

Background: Studies have suggested that replacing saturated fatty acids (SFAs) with carbohydrates is modestly associated with a higher risk of ischemic heart disease, whereas replacing SFAs with polyunsaturated fatty acids is associated with a lower risk of ischemic heart disease. The effect of carbohydrates, however, may depend on the type consumed.

Objectives: By using substitution models, we aimed to investigate the risk of myocardial infarction (MI) associated with a higher energy intake from carbohydrates and a concomitant lower energy intake from SFAs. Carbohydrates with different glycemic index (GI) values were also investigated.

Design: Our prospective cohort study included 53,644 women and men free of MI at baseline.

Results: During a median of 12 y of follow-up, 1943 incident MI cases occurred. There was a nonsignificant inverse association between substitution of carbohydrates with low-GI values for SFAs and risk of MI [hazard ratio (HR) for MI per 5% increment of energy intake from carbohydrates: 0.88; 95% CI: 0.72, 1.07). In contrast, there was a statistically significant positive association between substitution of carbohydrates with high-GI values for SFAs and risk of MI (HR: 1.33; 95% CI: 1.08, 1.64). There was no association for carbohydrates with medium-GI values (HR: 0.98; 95% CI: 0.80, 1.21). No effect modification by sex was observed.

Conclusion: This study suggests that replacing SFAs with carbohydrates with low-GI values is associated with a lower risk of MI, whereas replacing SFAs with carbohydrates with high-GI values is associated with a higher risk of MI.