Circadian Medicine and Children’s Health: Foundational Steps for Lifelong Prevention by Dr David Lescheid, ND, PhD

Circadian medicine validates ancient medical wisdom indicating that human health, from birth to death, is best supported when internal body rhythms are aligned with the rhythms of nature.[1] This article will briefly outline the influence of chronobiology on children’s health including common circadian rhythm disruptors and general steps[i] that support circadian biology and therefore, help maintain wellness and prevent disease.

All aspects of human physiology are influenced by 24-hour rhythms of sunlight and darkness including immune and endocrine systems, metabolic pathways in the liver and other organs, functions of organelles (eg. mitochondria) and the microbiome.[2] Major communication pathways including the hypothalamic-pituitary-adrenal axis, the microbiota-gut-brain axis, and the hypothalamus-pituitary-thyroid axis also are under circadian control.[2]

Supporting circadian rhythms during pregnancy may help infants establish ‘healthy’ circadian rhythms. Maternal circadian biology, including melatonin, glucocorticoid, dopamine, and metabolic rhythms, influences central fetal circadian rhythms and helps synchronize peripheral clocks within fetal cells, organs, and tissues.[1] External cues (eg. sunlight, temperature) and internal cues (eg. eating and exercise times, gut microbiota)[3]  coordinate the mother’s chronobiology and therefore, also could influence the baby’s chronobiology. Negative influences on the mother’s circadian rhythms (eg. artificial light at night, jet lag, social jet lag,[3] certain pharmaceutical drugs)[4] also could impact circadian rhythms within the infant.

Persistently altered circadian rhythms negatively influence children’s health including altering immunity to increase risk of infection and abnormal inflammation,[5] as well as increasing risk of allergic disorders such as allergic rhinitis, asthma, atopic dermatitis, and food allergy.[6] Mental health of children, including their ability to cope with and recover from various stressors, and their risk of attention deficit hyperactivity disorder,[7] also are associated with altered circadian rhythms and sleep disturbances.

Healthy eating, including what we eat as well as when we eat, helps maintain physiological circadian rhythms. Eating at regular times throughout the week and avoiding snacks a few hours before bedtime are simple steps that support natural circadian rhythms.[8] Establishing daily routines for sleeping, including creating darkness in the bedroom, without any influence from artificial light, both from within the room and from outdoors,[9] and cooling the temperature of the bedroom, also are helpful.[10] Minimizing exposure to electronic devices that emit blue light (eg. from cell phones, tablets and other electronic devices), especially before bedtime, also supports healthy circadian rhythms.[11] Recent research indicates that some young children may be particularly sensitive to the intensity of light in the hour before bedtime,[12] suggesting converting the bedroom in a ‘cave’ or dim-light environment may support healthy circadian rhythms.[13] Gut microbiota also maintain circadian rhythms that influence whole body physiology,[10] suggesting food habits and/or regular use of probiotics in children also support natural rhythms. The timing of exercise/ activity also influences circadian rhythms,[11] suggesting regular daily routines of activity and exercise are beneficial. The circadian system is a neural and molecular network that profoundly influences the balance between health and disease throughout our lifetime.[14] Practicing circadian medicine includes teaching patients of all ages to minimize their exposure to circadian rhythm disruptors as well as establish healthy lifestyle habits that are in harmony with our body’s natural rhythms. Teaching children lifestyle and dietary habits that support physiological circadian rhythms is an important step towards preventing numerous diseases in adulthood associated with circadian disruption including metabolic disorders such as obesity and non-alcoholic fatty liver disease (NAFLD),[ii] cancer, mood, and neurodegenerative disorders.[15]

[i] Circadian physiology is influenced by individual factors, including age, sex, genes, epigenetics and other factors contributing to various chronotypes (Montaruli A, Castelli L, et al., Biological Rhythm and Chronotype: New Perspectives in Health. Biomolecules. 2021 Mar 24;11(4):487). General medical advice is useful. However, for the best results any routines implemented to support circadian rhythms should be specifically tailored to the needs of the individual child.

[ii] NAFLD was renamed Metabolic dysfunction-associated steatotic liver disease (MASLD)
Rinella ME, Lazarus JV, NAFLD Nomenclature consensus group et al.. A multi-society Delphi consensus statement on new fatty liver disease nomenclature. J Hepatol. 2023 Jun 20:S0168-8278(23)00418-X

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