In the first human study of its kind, researchers from the University of Surrey discovered that delaying meal times delays the circadian rhythm of sugar in the blood. The findings could prove to be a breakthrough in alleviating symptoms of jet lag and shift work, a new study in the journal Current Biology reports.
During this innovative study, Dr Jonathan Johnston and Dr Sophie Wehrens from the University of Surrey examined the impact of altering meal times on the circadian rhythms of ten volunteers. Circadian rhythms are approximately 24-hour changes governed by the body’s internal clocks and determine many physiological processes in the body.
Volunteers were provided with three meals breakfast, lunch and dinner. In the first phase of the study, the first meal was provided 30 minutes after waking, with later meals at subsequent five hour intervals whilst in the second phase each meal was delayed by five hours after waking. Immediately after each phase, sequential blood samples and fat biopsies were taken from each volunteer in specialised laboratory conditions that allow measurement of internal circadian rhythms.
Researchers discovered that postponing meal times by five hours delayed rhythms of blood sugar by the same time frame. This discovery demonstrates that mealtimes synchronise internal clocks that control rhythms of blood sugar concentration. Researchers indicated that people who struggle with circadian rhythm disorders, including shift workers and long haul flights, might consider timed meals to help resynchronize their body clocks.
Surprisingly researchers uncovered that the delay in meal times did not affect insulin or triglyceride (fat) levels in the blood indicating that blood sugar rhythms can be governed by separate circadian clocks to these other key aspects of rhythmic metabolism.
Lead investigator of the study, Dr Jonathan Johnston, from the University of Surrey said: “It has been shown that regular jet lag and shift work have adverse effects on the body, including metabolic disturbances.
“Altering meal times can reset the body clocks regulating sugar metabolism in a drug free way. This will help us design feeding regimes to reduce the risk of developing health problems such as obesity and cardiovascular disease in people with disturbed circadian rhythms.”
External Relations and PR Officer
University of Surrey Press Office
- Out-of-hours: +44 (0)7773 479911
Senate House, University of Surrey
Guildford, Surrey GU2 7XH
Dr Jonathan Johnston
Reader in Chronobiology and Integrative Physiology
Dr Dr Sophie Wehrens
Research Integrity and Governance Officer