Various versions of the intermittent fasting diet appear to have weight loss benefits, however a new study sheds some light on just why.
In a University of California, Irvine-led study, researchers found evidence that fasting affects circadian clocks in the liver and skeletal muscle, causing them to rewire their metabolism, which can ultimately lead to improved health and protection against ageing-associated diseases.
The study, published in Cell Reports, was conducted using mice, which were subjected to 24-hour periods of fasting. While fasting, researchers noted the mice exhibited a reduction in oxygen consumption (VO2), respiratory exchange ratio (RER), and energy expenditure, all of which were completely abolished by refeeding, which parallels results observed in humans.
“We discovered fasting influences the circadian clock and fasting-driven cellular responses, which together work to achieve fasting-specific temporal gene regulation,” said lead author Paolo Sassone-Corsi, Donald Bren Professor of Biological Chemistry at UCI’s School of Medicine. “Skeletal muscle, for example, appears to be twice as responsive to fasting as the liver.”
Daily sleep–wake cycles, or circadian rhythms, drive the ebb and flow of human life; they control much more than just our sleepiness levels. Our 24-hour cycles involve metabolic, physiological, and behavioral changes that impact every tissue of the body.
Fasting is a natural phenomenon for most animals, because food is not always readily available. In times of hardship, certain metabolic changes occur to allow the body to adapt.
The scientists believe that having more clearly defined cycles might be part of the reason that fasting promotes good health.
The study opens new avenues of investigation that could ultimately lead to the development of nutritional strategies to improve health in humans.