Can you tell me the physical effects of fasting?
For thousands of years, people have fasted for religious and health-related purposes. As a consequence of similar evolutionary pressures experienced by our hunter-gatherer forebears, our bodies have adapted to fasting for longer durations than ours.
When we fast, our bodies shift their fuel source from glucose, which is readily available, to fat. Little is known, however, about the physiological reactions to prolonged fasting beyond this shift in fuel source.
A recent study was published in the journal Nature Metabolism. It tracked 12 healthy volunteers for seven days while they fasted on water alone. The researchers came from Queen Mary University in London and the Norwegian School of Sport Sciences. A brief picture of the body’s reaction to its changing environment was provided by regularly monitoring the participants to detect variations in the amounts of numerous protein markers in their blood.
As predicted, the researchers noticed the subjects moving from glucose to fat as their principal fuel source during the first two to three days of fasting. On average, the participants shed 5.9 kg of fat and 5.9 kg of muscle. However, the researchers also detected different alterations in the patients’ blood indicators after around three days of fasting.
Their data reveal that three days of fasting produce a whole-body reaction. Of particular significance were modifications in the proteins that make up the supporting framework for our brain cells.
“For the first time, we’re able to see what’s happening on a molecular level across the body when we fast,” Claudia Langenberg, Director of Queen Mary’s Precision Health University Research Institute (PHURI), said in a statement. “Fasting, when done properly, is an effective weight loss technique. There are health advantages to fasting that go beyond only weight reduction, according to popular fasting regimens like intermittent fasting.
“Our results provide evidence for the health benefits of fasting beyond weight loss, but these were only visible after three days of total caloric restriction—later than we previously thought.”
It is crucial to realize that, although the findings were similar among individuals, the research was conducted on a relatively small cohort. It remains to be seen if the findings will be duplicated on a wider scale.
There are also those for whom fasting is not an option.
“While fasting may be beneficial for treating some conditions, often times, fasting won’t be an option for patients suffering from ill health,” Maik Pietzner, Health Data Modeling Chair of PHURI and co-lead of the Computational Medicine Group at the Berlin Institute of Health at Charité, said in a statement.
“We hope that these findings can provide information about why fasting is beneficial in certain cases, which can then be used to develop treatments that patients are able to do.”
Anyone interested in researching complete calorie restriction should talk to a medical expert before making dramatic changes to their diet.
NEWS SOURCE: NEWSWEEK
