Intermittent Fasting, Insufficient Sleep, and Circadian Rhythm: Interaction and Effects on the Cardiometabolic System
Purpose of Review
Sleep, circadian rhythms, and fasting/feeding are important factors that affect cardiometabolic function. Here, we review recent studies that assessed the role of intermittent fasting, short sleep duration, and circadian rhythm disruption, as well as their interactions, on the risk of cardiometabolic dysfunction.
The cardiometabolic system is sensitive to sleep, circadian rhythms, and fasting/feeding patterns. Recent data show that these factors may influence each other and hence, directly or indirectly affect cardiometabolic risk. Fasting/feeding schedules and mealtimes may cause misalignment of the circadian system resulting in several cardiometabolic disturbances. Recent data reveal that intermittent fasting (IF) improves several cardiometabolic indicators in both laboratory animals and humans maintained on IF diets during alternate day fasting, diurnal IF, or time-restricted feeding. However, most of the human studies recruited a modest number of participants and did not control for several confounding factors that may have affected the measurement of cardiometabolic parameters, such as sleep duration and timing, energy expenditure, and light exposure.
Current evidence shows that IF, sleep, and circadian rhythms can affect cardiometabolic risk both individually or collectively. IF, adequate sleep, and matching mealtimes with the circadian clock improve several cardiometabolic parameters. More extensive human studies that assess the interaction between the three factors in the general population are needed to complement the currently available short-term laboratory-based human studies.
KeywordsDiurnal fasting Sleep Biological clock Cardiometabolic disease Time restricted feeding Ramadan
The authors thank the Deanship of Scientific Research and RSSU at King Saud University for their technical support.
This work was supported by the Strategic Technologies Program of the National Plan for Sciences and Technology and Innovation in the Kingdom of Saudi Arabia (MED511-02-08).
Compliance with Ethical Standards
Conflict of Interest
Aljohara S. Almeneessier declares no conflicts of interest.
Ahmed S. BaHammam declares no conflicts of interest.
Seithikurippu R. Pandi-Perumal declares no conflict of interest. Pandi-Perumal is the President and Chief Executive Officer of Somnogen Canada Inc. Pandi-Perumal has edited several academic volumes for which he will receive annual royalties.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance
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