Intermittent fasting is up there with one of the most popular ways to lose weight. Its rise to stardom in the present-day — fasting has a long history — has caused health experts to question its effectiveness and safety. There are myriad fasting diets: the 5:2, 16:8, the Eat, Stop, Eat.
Proponents of the diet claim it brings all manner of benefits, including weight loss, significant falls in blood pressure, blood sugar and cholesterol.
Jack Dorsey, the CEO of Twitter, was one of the most high-profile names in recent years to announce he ate just one meal a day.
Many critics called it an extreme diet.
Yet, scientists at the University of British Columbia in Canada recently carried out an experiment which suggests fasting may have another feather to add to its cap.
BBC Science Focus magazine described the results as showing that fasting “may help protect against infection”.
When humans or animals develop an infection, they often lose their appetite.
However, it has so far remained unclear as to whether fasting could protect a host from infection or increase their susceptibility to it.
To test this, the researchers fasted a group of mice for 48 hours and orally infected them with Salmonella enterica serovar Typhimurium — a bacteria responsible for a high proportion of cases of gastroenteritis in humans.
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These were mice bred to lack a normal microbiome.
It suggested that some of the effect was due to changes in the animals’ gut microbiomes.
The microbiome appears to sequester the nutrients that remain when food is limited.
This prevents pathogens from acquiring the energy they need to infect the host, according to the team.
Dr Bruce Vallance, a co-author of the study, said: “We saw an overall change in the composition of the microbiome, meaning an increase in some bacteria and a decrease in other bacteria.
“However, we did not show in our study which bacteria specifically are responsible for the protective effect, just that the microbiome as a whole is mediating most of the protective effect of fasting since mice lacking a microbiome — germ free mice — are not as protected from the infection.”
The team now plan to investigate the effect of fasting on the microbiome with the time of establishing whether the absence or presence of specific bacteria are responsible for the protective effect.
Fasting is not a new practice.
It has been practiced throughout history for religions, cultural and spiritual reasons.
But as a way of eating it goes back much further.
Our ancestors had periods of enforced fasting.
Hunter-gatherers only had food when they killed or collected it, so fasting was part of their everyday reality.
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