We are increasingly moving away from regular meals as more meals are being eaten outside the home and families dining together has been eroded by hectic schedules.

 In a study conducted at the Queens Medical Center in United Kingdom, irregular meal frequency disturbed energy metabolism in healthy lean women leading to a lower postprandial energy expenditure, higher degree of insulin resistance or lower post meal insulin sensitivity and higher fasting lipid profiles, thereby indicating a deleterious effect on these cardiovascular disease risk factors (Farsshchi H). A more evenly spaced pattern of 3 meals per day with no snacks was more strongly associated with a lower prevalence of overweight and obesity and a nutritionally higher-quality diet (McCrory). Also, prolonged intervals between meals and skipping meals may trigger migraines and hypoglycemia in some individuals.

Physiological responses to what and how much we eat represent the foundation for translational as well as basic science aimed at preventing and treating metabolic diseases including obesity and diabetes, However, the timing of food consumption independent of total caloric intake and macronutrient quality has emerged as a critical factor in maintaining metabolic health. Panda S, in his paper states that when healthy adults eat identical and iso-caloric (same calorie ) meals at breakfast, lunch, or dinner, the post meal glucose rise is lowest after breakfast and highest after dinner as if the dinner were twice the size of the breakfast. In addition, when healthy adults are given a constant glucose infusion over 24 hours, blood glucose rises at night and falls around dawn. This is likely because melatonin inhibits insulin release from pancreatic islets through the melatonin receptor and the evening rise in melatonin likely causes hyperglycemia. This indicates that in addition to what and how much we eat, when we eat helps determine the physiological response to nutrient availability (Panda S and Reid K).

Almost every cell in the body has a circadian clock machinery, each with an approximately 24 h period. Circadian rhythms are an integral part of physiology that seem to be essential for health. The circadian system is a master integrator of both the internal state of the organism and the organism’s interaction with nutrition and ambient light. The suprachiasmatic nucleus (SCN) in the hypothalamus acts as a master clock to coordinate independent oscillators throughout the body and determine the period of the organism. Unlike peripheral oscillators, the SCN is composed of a network of neurons with intricate intercellular communication to produce robust outputs through both neural and humoral cues. In addition to this internal regulation, the SCN also receives external input, such as light, to help an organism coordinate with their environment. Nutrient consumption also has a large influence on biological rhythms, but has a more direct effect on peripheral oscillators than the SCN. Together, light and nutrients coordinate internal biological rhythms with the environment

Erratic lifestyle associated with modern society - aberrant eating and sleep patterns, inappropriate light exposure, jet-lag, and shift work contribute to circadian rhythm disruption. This disruption compromises multiple levels of physiology. metabolism, and inflammation and increases the risk for non-infectious chronic diseases such as metabolic disorder, diabetes, cardiovascular disease, and cancer. Light at night suppresses sleep and promotes extended wakefulness, thereby allowing ingestive behavior to continue late into the night. Therefore, room lighting/ darkness is critical during sleep. It is important to keep bedrooms as dark as possible and avoid blue light before sleep. Conversely, maintaining a consistent daily eating and fasting rhythm and sleeping in dark room maintains normal circadian physiology and can prevent or mitigate several of these chronic disease. a consistent daily pattern of eating and fasting maintains normal circadian physiology (Manoogian E and Jian P).

1.     Farsshchi H Taylor M Macdonald I. Beneficial metaboloc effects of regular meal frequency on dietary thermogenesis, insulin sensitivity, and fasting lipid profiles in healthy obese women. American Journal of Clinical Nutrition. 2005 Jan;81(1):16-24 https://www.ncbi.nlm.nih.gov/pubmed/15640455

 2.     McCrory M Shaw A Lee J. Energy and nutrient timing for weight control: Does timing of ingestion matter? Endocrinology and Metabolism Clinics of North America. 2016 Sep;45(3):689-718. doi: 10.1016/j.ecl.2016.04.017.  https://www.ncbi.nlm.nih.gov/pubmed/27519140

3.     Panda S. Circadian physiology of metabolism. Science. 2016 Nov 25;354(6315):1008-1015. DOI: 10.1126/science.aah4967  http://science.sciencemag.org/content/354/6315/1008

 4.     Reid K Baron K Zee P. Meal timing influences daily caloric intake in healthy adults.  Nutrition Research. 2014 34(11): 930–935. doi:10.1016/j.nutres.2014.09.010 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4794259/

 5.     Manoogian E Panda S. Circadian rhythms, time restricted feeding, and healthy aging. Ageing Research Reviews. 2016 2016 Dec 23. pii: S1568-1637(16)30301-4. doi: 10.1016/j.arr.2016.12.006 https://www.ncbi.nlm.nih.gov/pubmed/28017879

6.     Jian P Turek F. Timing of meals: When is as critical as what and how much. American Journal of Physiology- Endocrinology and Metabolism. 2017 2017 Jan 31:ajpendo.00295.2016. doi: 10.1152/ajpendo.00295 https://www.ncbi.nlm.nih.gov/pubmed/28143856

Author: Aarti Batavia MS, RDN, CLT, CFSP, IFMCP

Institute for Functional Medicine Certified Practitioner

Adjunct Faculty - Wayne State University - Coordinated Program in Dietetics.