Although it is popularly known that fasting may help people lose weight, a new research suggests that going without food may also boost human metabolic activity, generate antioxidants and help reverse some effects of ageing.
The researchers, who are scientists at the Okinawa Institute of Science and Technology Graduate University and Kyoto University, Japan, identified 30 previously unreported substances that increased during fasting and indicates a variety of health benefits.
The first author of the paper and a technician in the OIST G0 Cell Unit, Dr Takayuki Teruya, said the team had been researching aging and metabolism for many years and decided to search for unknown health effects in human fasting.
“Contrary to the original expectation, it turned out that fasting-induced metabolic activation rather actively,” Teruya said.
The study, according to sciencedaily.com, presented an analysis of the 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 unrecognised, that increased universally among subjects between 1.5 and 60 fold within just 58 hours of fasting.
Teruya said, “In previous research, the G0 Cell Unit identified various metabolites that decline in quantity 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. This result suggests the possibility of a rejuvenating effect by fasting, which was not known until now.”
In their comprehensive analysis of the human blood, the researchers noted that fasting appeared to elicit effects far beyond energy substitution, thus establishing fasting markers and many more. For example, they found a global increase in substances produced by the citric acid cycle, a process by which organisms release energy stored in the chemical bonds of carbohydrates, proteins and lipids. The marked increase suggested that, during fasting, the tiny powerhouses running every cell are thrown into overdrive.
Fasting also appeared to enhance the metabolism of purine and pyrimidine, chemical substances which play key roles in gene expression and protein synthesis.
The finding suggested that fasting may re-programme which proteins cells build at what time, thus altering their function. The change, the scientists said, may promote homeostasis in cells, or serve to edit their gene expression in response to environmental influences.
The authors suggested that anti-oxidative effects may stand as the body’s principal response to fasting, as starvation can foster a dangerously oxidative internal environment. Their exploratory study provided the first evidence of antioxidants as a fasting marker. In addition, the study introduced the novel notion that fasting might boost production of several age-related metabolites, abundant in young people, but depleted in old.
“Recent ageing studies have shown that caloric restriction and fasting have a prolonging effect on lifespan in model animals, but the detailed mechanism has remained a mystery. It might be possible to verify the anti-ageing effect from various viewpoints by developing exercise programs or drugs capable of causing the metabolic reaction similar to fasting.
“People are interested in whether human beings can enjoy the effects of prevention of metabolic diseases and prolonging life span by fasting or caloric restriction, as with model animals. Understanding the metabolic changes caused by fasting is expected to give us wisdom for maintaining health,” Teruya said.