Because it is unknown whether breakfast frequency and timing are associated with long-term risk of incident myocardial infarction (MI) and coronary artery disease (CAD) among older adults, this study aimed to assess relationships between breakfast frequency/timing and MI/CAD risk among older adults and determine whether they depend on sex or cardiometabolic risk factors.

Prospective cohort study of older American adults.

Weekly breakfast frequency and usual daily breakfast time were assessed by questionnaire in 4070 adults aged ≥ 65 years from the Cardiovascular Health Study who were prospectively followed for up to 26 years. Cause-specific hazard ratios (HRs) with 95% confidence intervals (CIs) were estimated from multivariable-adjusted Cox proportional hazards models.

During follow-up, 1617 CAD cases were documented (795 MI cases). Although consuming breakfast 7 days/week (85.3%) and ‘breaking-fast’ between 07:00 and 09:00am (72.6%) were both associated with higher education and socioeconomic status, being married, not smoking, and consuming fruits and vegetables, neither breakfast frequency nor breakfast timing was associated with risk of CAD or MI in males, females, or altogether. In pre-specified analyses, compared with participants who ate breakfast daily, those who did not eat breakfast daily had an HR for MI of 0.66 (95% CI: 0.43, 1.02) if their body mass index (BMI) was ≥30 kg/m ² and of 1.17 (0.91, 1.51) if their BMI was < 30 kg/m ² (interaction p = 0.02). Compared with participants whose breakfast time was 07:00–09:00, those who broke their fast before 07:00 had an HR for CAD of 1.40 (1.02, 1.93) if they had type 2 diabetes and of 1.19 (1.03, 1.38) if they had high fasting insulin at baseline.

Breakfast frequency and timing were not associated with either higher or lower risk of MI and CAD in these older adults. Although a priori stratification by cardiometabolic risk factors may have revealed potential trends, the findings must be confirmed in a larger study.