Reference
Rong S, Snetselaar LG, Xu G, et al. Association of skipping breakfast with cardiovascular and all-cause mortality. J Am Coll Cardiol. 2019;73(16):2025-2032.
Study Objective
The authors examined the association of skipping breakfast with cardiovascular and all-cause mortality.
Design
This is a prospective cohort study. Frequency of eating breakfast was compared to cardiovascular and all-cause mortality risk using weighted Cox proportional hazards regression models.
Participants
The study followed a cohort of 6,550 US adults, 40 to 75 years of age, who participated in the National Health and Nutrition Examination Survey III 1988 to 1994. Frequency of breakfast eating was recorded during an in-house interview. Death and underlying causes of death were ascertained by linkage to death records through December 31, 2011.
Key Findings
In following this cohort for 17 to 23 years, the researchers found that skipping breakfast was associated with a significantly increased risk of mortality from cardiovascular disease. Of the cohort, 59% consumed breakfast daily. The other 40% ate breakfast less frequently: 5% never ate breakfast, 11% rarely ate breakfast, and 25% ate only on some days. The study produced 112,148 person-years of follow up data, during which 2,318 deaths occurred, including 619 deaths from cardiovascular disease (CVD).
After adjustment for age, sex, race/ethnicity, socioeconomic status, dietary and lifestyle factors, body mass index, and cardiovascular risk factors, participants who never consumed breakfast compared with those who consumed breakfast everyday had hazard ratios of 1.87 (95% confidence interval [CI]: 1.14-3.04) for cardiovascular mortality and 1.19 (95% CI: 0.99-1.42) for all-cause mortality. The latter upward trend did not reach statistical significance.
After adjustment for age, sex, and race/ethnicity, participants who never consumed breakfast had a 75% higher risk of all-cause mortality (hazard ratio [HR]: 1.75; 95% CI: 1.46-2.10) and 2.58-fold higher risk of cardiovascular mortality (HR: 2.58; 95% CI: 1.64-4.06) compared with those who consumed breakfast every day. The associations of breakfast eating with heart disease–specific and stroke-specific mortality were examined further. Compared with those who consumed breakfast every day, participants who never consumed breakfast had a higher risk of heart disease–specific mortality (HR: 2.34; 95% CI: 1.44-3.80) and stroke-specific mortality (HR: 3.53; 95% CI: 1.40-8.95) in models adjusted for age, sex, race/ethnicity. In the fully-adjusted model, the association between skipping breakfast and stroke-specific mortality remained significant (HR: 3.39; 95% CI: 1.40-8.24).
Practice Implications
According to this study eating breakfast regularly reduces risk of dying from cardiovascular disease and probably stroke. Or, put another way, not eating breakfast raises risk significantly. We should foster in our patients the habit of eating breakfast.
Keep in mind that more people die of cardiovascular disease than any other cause—not just in the United States but worldwide.1 Even small decreases in risk have the potential of having large impacts on disease and suffering.
We often hear that “breakfast is the most important meal of the day.” I had always assumed this was merely an advertising slogan invented by Kellogg’s to sell their breakfast cereals a century ago. Surveys tell us that almost a quarter of younger people skip breakfast daily.2,3 It looks as though this may have long-term detrimental effects on their health.
Accumulating evidence, while limited, suggests that skipping breakfast is associated with increased risk of overweight/obesity,4 dyslipidemia,5 hypertension,6 type 2 diabetes,7 metabolic syndrome,8 coronary heart disease,9 and cerebrovascular disease.10
It’s not just about eating breakfast. Skipping breakfast may also signal other unhealthy dietary and lifestyle habits. Teenagers who skip breakfast tend to exhibit a list of other traits that may also put their health at risk (eg, eating more fast food, having more emotional problems).11 Asking patients if they eat breakfast is similar in a way to the old patient intakes in which we asked patients if they used seatbelts. A negative response may hint to a pattern of unhealthy lifestyle choices.
Asking patients if they eat breakfast is similar in a way to the old patient intakes in which we asked patients if they used seatbelts. A negative response may hint to a pattern of unhealthy lifestyle choices.
This is not the first study to suggest a negative association with skipped breakfasts. Cahill et al reported in 2013 that they had assessed the eating habits of 26,902 American men from the Health Professionals Follow-up Study. During a 16-year period, 1,527 cases of heart disease were diagnosed among these men. Men who skipped breakfast had a 27% higher risk of coronary heart disease (CHD) compared with men who did not (relative risk (RR): 1.27; 95% CI: 1.06-1.53). Furthermore, we should note that men who ate late at night had a 55% higher CHD risk compared with men who did not eat late at night (RR: 1.55; 95% CI: 1.05-2.29).9
Kubota et al reported results in a 2016 paper from a large group that included 82,772 participants (38,676 men and 44,096 women) in Japan. Those people who skipped breakfast had a 14% greater risk of CVD, an 18% increased risk of stroke, and a 36% greater risk of hemorrhagic stroke.10
The discussion now is not if skipping breakfast is bad by why. Several theories have been postulated. Skipping breakfast might lead to overeating later in the day and impaired insulin sensitivity.12 Eating breakfast helps regulate the appetite and improves the glycemic response at the next meal, increasing insulin sensitivity.13 Skipping breakfast is stressful, and the longer period of fasting leads to elevated blood pressure in the morning because of a hypothalamic-pituitary adrenal triggered response.6
Eating breakfast on the other hand lowers blood pressure and reduces arterial stiffness. This is why measurements of these parameters are done in a fasting state.14 Skipping breakfast may also trigger unwanted changes in blood lipids, in particular increased LDL cholesterol.5
Whatever the reasons, data consistently shows skipping breakfast increases risk of cardiovascular disease. The advice to have breakfast may meet with resistance among those who fast overnight for their health.
Carol Marinac, in a 2016 paper noted the association of longer night-time fasting and lower risk of breast cancer recurrence. Specifically, the data showed that those who fasted more than 13 hours had less breast cancer recurrence.15 We covered this study in 2016.
The problem with encouraging this type of fasting is that many people fulfill the 13-hour fasting suggestion by simply skipping breakfast. The resultant increase in CVD risk might outweigh any breast cancer risk reduction. We need an approach that will allow both a longer night-time fast and encourage eating breakfast, so the obvious solution would be to eat an earlier dinner. Such a meal pattern of eating an early dinner was encouraged by Kogevinas et al’s 2018 study. In those results, compared to participants who went to sleep immediately or shortly after supper, those who delayed going to sleep for 2 or more hours after supper had a 20% reduction in risk for breast and prostate cancer combined (adjusted odds ratio [OR]: 0.80; 95% CI: 0.67-0.96) and in each cancer individually (prostate cancer OR: 0.74; 95% CI: 0.55-0.99 and breast cancer OR: 0.84; 95% CI: 0.67-1.06).16 Read our coverage of that study.
If we combine Kogevinas’s findings with Marianac’s, then we should encourage an early dinner (minimum of 2 hours before bedtime) and then breakfast 13 hours later. Once again, the research suggests that when we eat may deserve as much attention as what we eat.