Dietary protein and risk of ischemic heart disease in middle-aged men

Am J Clin Nutr. 2010 Nov;92(5):1265-72. doi: 10.3945/ajcn.2010.29626. Epub 2010 Sep 29.

Abstract

Background: Prospective studies in US women have suggested an inverse relation between dietary protein and risk of ischemic heart disease (IHD). However, no large-scale prospective studies have been conducted in US men.

Objective: The objective was to examine the association between dietary protein and risk of IHD in a prospective study of US men.

Design: Intakes of protein and other nutrients were assessed by using a validated food-frequency questionnaire at 4 time points during follow-up of 43,960 men participating in the Health Professionals Follow-Up Study. Cox proportional hazards models were used to calculate multivariable-adjusted relative risks (RRs) and 95% CIs.

Results: During 18 y of follow-up, we documented 2959 incident cases of IHD. The RR of IHD was 1.08 (95% CI: 0.95, 1.23; P for trend = 0.30) comparing the top with the bottom quintile of percentage of energy from total protein. RRs for animal and vegetable protein were 1.11 (95% CI: 0.97, 1.28; P for trend = 0.18) and 0.93 (95% CI: 0.78, 1.12; P for trend = 0.49), respectively. When the population was restricted to "healthy" men (those free of hypertension, hypercholesterolemia, and diabetes at baseline), the RR of IHD was 1.21 (95% CI: 1.01, 1.44; P for trend = 0.02) for total protein, 1.25 (95% CI: 1.04, 1.51; P for trend = 0.02) for animal protein, and 0.93 (95% CI: 0.72, 1.19; P for trend = 0.65) for vegetable protein.

Conclusions: We observed no association between dietary protein and risk of total IHD in this group of men aged 40-75 y. However, higher intake of animal protein may be associated with an increased risk of IHD in "healthy" men.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • Aged
  • Dietary Proteins / administration & dosage*
  • Dietary Proteins / adverse effects
  • Humans
  • Incidence
  • Male
  • Meat
  • Middle Aged
  • Myocardial Ischemia / epidemiology*
  • Myocardial Ischemia / etiology
  • Myocardial Ischemia / prevention & control
  • Plant Proteins* / adverse effects
  • Proportional Hazards Models
  • Prospective Studies
  • Reference Values
  • Risk Factors
  • Surveys and Questionnaires
  • United States / epidemiology

Substances

  • Dietary Proteins
  • Plant Proteins