Fasting ramps up human metabolism, study shows
Fasting may help people lose weight, but new research suggests going without food may also boost human metabolic activity, generate antioxidants, and help reverse some effects of aging. Scientists at the Okinawa Institute of Science and Technology Graduate University (OIST) and Kyoto University identified 30 previously-unreported substances whose quantity increases during fasting and indicate a variety of health benefits.
"We have been researching aging and metabolism for many years and decided to search for unknown health effects in human fasting," said Dr. Takayuki Teruya, first author of the paper and a technician in the OIST G0 Cell Unit, led by Prof. Mitsuhiro Yanagida. "Contrary to the original expectation, it turned out that fasting induced metabolic activation rather actively."
The study, published January 29, 2019 in Scientific Reports, presents an analysis of whole human blood, plasma, and red blood cells drawn from four fasting individuals.
The researchers monitored changing levels of metabolites -- substances formed during the chemical processes that grant organisms energy and allow them to grow.
The results revealed 44 metabolites, including 30 that were previously unrecognized, that increased universally among subjects between 1.5- to 60-fold within just 58 hours of fasting.
In previous research, the G0 Cell Unit identified various metabolites whose quantities decline with age, including three known as leucine, isoleucine, and ophthalmic acid.
In fasting individuals, these metabolites increase in level, suggesting a mechanism by which fasting could help increase longevity.
"These are very important metabolites for maintenance of muscle and antioxidant activity, respectively," said Teruya. "This result suggests the possibility of a rejuvenating effect by fasting, which was not known until now."