Female breakfast skippers display a disrupted cortisol rhythm and elevated blood pressure
Introduction
Breakfast skipping is prevalent and occurs regularly in 20% of US adults [1]. Among young men, minorities and the economically disadvantaged, this phenomenon is even higher [2], [3]. Habitual breakfast skipping may be detrimental to health [4] and has been linked to elevated blood pressure [5], insulin resistance [6], and dyslipidemia [7]. While associations between breakfast skipping and BMI, or increased energy intake have been reported [1], [8], [9], [10], recent evidence disputes these claims [11], [12]. Differences in the physiological response to skipping breakfast may explain the apparent discrepancies. However, a physiological basis connecting regular breakfast skipping and poor metabolic health is unclear. Given the negative effects of chronically elevated cortisol on metabolic health [13], [14], [15], [16], cortisol increases in response to skipping breakfast may, over time, promote risk for metabolic dysfunction. Persistent increases in cortisol are linked to hyperglycemia [17], insulin resistance [15], abdominal obesity [18], and high blood pressure [19].
In one of the few human studies looking at the frequency of breakfast intake and circulating cortisol concentrations, individuals eating breakfast every day had lower daytime mean salivary cortisol than those individuals who never ate breakfast [20]. In another study, breakfast skipping accounted for 22% of the inverse association between socioeconomic status and salivary cortisol [21]. In rodents, preventing consumption of the first meal of the day (lights off) significantly elevates corticosterone, which resolves when the animals are allowed to eat [22]. This phenomenon has not been well documented in humans.
We hypothesized that self-reported breakfast skippers would have elevated circulating cortisol, particularly during the morning and up until lunch. Secondly, we hypothesized cardiometabolic disease risk factors including insulin sensitivity, lipid profile, waist to hip circumference, and blood pressure will be higher in breakfast skippers, relative to breakfast eaters. Thirdly, we hypothesized that ongoing (chronic) stress may be more prominent in breakfast skippers and may contribute to elevated cortisol.
Section snippets
Participants and recruitment
The Institutional Review Board at the University of California, Davis, approved the protocol. Based on the following criteria, women were invited to participate in a cross sectional observational study. Participants were premenopausal aged 18 to 45 years with a BMI of less than 40 kg/m2, weight stable, maintained a typical diurnal schedule and were classified as either being “breakfast eaters” or “breakfast skippers.” A breakfast eater was defined as someone who consumed at least 15% of their
Participants and anthropometric measures
Sixty-five women (n = 35 breakfast eaters, n = 30 breakfast skippers) completed all visits and were included in the final analyses. Body weight, BMI, fat mass, fat free mass, waist to hip ratio, total cholesterol, and HDL cholesterol measured at screening were not different between breakfast conditions (p > 0.05). However, LDL cholesterol was lower and systolic and diastolic blood pressures were higher in the skipper group (p = 0.043, p = 0.003, p = 0.009, respectively) (Table 3). Fasting glucose and
Discussion
The mechanisms linking breakfast skipping and poor health are unclear. Breakfast is typically consumed after an extended fast and after a period of sleep. It has been proposed that the typically elevated waking cortisol promotes arousal and drive to eat [36], [37]. When breakfast is consumed, cortisol steadily drops. In meal-trained rats, if the first meal is missed, corticosterone (primary glucocorticoid in rodents) concentrations remain elevated hours after it would typically fall [22], [35],
Conclusion
In conclusion, our results suggest that breakfast skippers have prolonged daily elevations in cortisol, which may explain higher blood pressure and other previously described cardiometabolic dysfunction in persons habitually skipping breakfast. We did not find other cardiometabolic disease risk factors to be elevated in breakfast skippers. However, if this breakfast skipping along with altered cortisol activity persists, development of chronic disease is possible [67]. The women in our study
Funding/support
This research was supported with funding from USDA-CSREES NRI grant 2009-35215-05364 and USDA Agricultural Research Service intramural project number 5306-51530-019-00.
Acknowledgments
The USDA is an equal opportunity provider and employer.
References (68)
Is consumption of breakfast associated with body mass index in US adults?
J. Am. Diet. Assoc.
(2005)- et al.
Differences in food patterns at breakfast by sociodemographic characteristics among a nationally representative sample of adults in the United States
Prev. Med.
(2000) Is consumption of breakfast associated with body mass index in US adults?
J. Am. Diet. Assoc.
(2005)Skipping breakfast: longitudinal associations with cardiometabolic risk factors in the Childhood Determinants of Adult Health Study
Am. J. Clin. Nutr.
(2010)Association of breakfast intake with cardiometabolic risk factors
J. Pediatr. (Rio J.)
(2013)- et al.
Nutrient contribution of breakfast, secular trends, and the role of ready-to-eat cereals: a review of data from the Bogalusa Heart Study
Am. J. Clin. Nutr.
(1998) Meal and snack patterns are associated with dietary intake of energy and nutrients in US adults
J. Am. Diet. Assoc.
(2006)Associations of salivary cortisol levels with inflammatory markers: the Multi-Ethnic Study of Atherosclerosis
Psychoneuroendocrinology
(2012)Assessment of adrenal suppression in children with asthma treated with inhaled corticosteroids: use of dehydroepiandrosterone sulfate as a screening test
Ann. Allergy Asthma Immunol.
(2006)- et al.
Trends in breakfast consumption of US adults between 1965 and 1991
J. Am. Diet. Assoc.
(1996)