The popular concept says that the products that have fallen to the floor can be safely eaten if they are lifted in a matter of moments. We checked whether this is so.

There is such a popular saying: "Quickly raised by the fallen is not considered." Nowadays, a whole theory corresponds to it, in the name of which there are five (sometimes ten) seconds. According to formal justification, microbes that have time to switch to fallen food during this period will be so few that they will be easily destroyed by gastric acid and will not harm the body. The observation applies to purely hard food and, as a rule, does not apply to cases when obvious traces of dirt remain on food.

Periodically fall into the press results Separate studies on this topic, in which the concept is directly or indirectly confirmed. In parallel, a high percentage of people is indicated, at least once eared food that fell to the floor (79%of the above link). And, as is customary, in such news usually appears British scientists.

The principle that has been the basis of the rules of five seconds has been known for a long time. Microbiologist Brian Sheldon and food specialist Paul Dawson in his book "Have you just eaten it?»Build history to legends about Genghis Khan. The ruler of the Mongols at his feasts used the so -called “Khan’s rule”: if the food fell to the floor, it remained there until Genghis Khan allowed it to raise it. It was believed that the dishes prepared for Genghis Khan were special - they could be eaten after any tests.

Many centuries have passed, and people learned about such a thing as bacteria. Moreover, it turned out that bacteria can enter our body through food and cause different diseases, up to the most serious. An important role in this was played Research by Louis Pasteur.

However, in parallel, academic science among ordinary people also developed their ideas about the framework of the permissible. What used to be just abstract opinions began to be formalized in the form of a “folk” theory in the 90s of the XX century. According to the popular science resource Science Friday, for the first time in the English -language press, such a rule in combination with the number of seconds is mentioned in the novel by Brad Lewis "The coach is sought by an academic rowing"published in 1995. Lewis is about 20 seconds, but the hero of the 2001 film "Osmosis Jones"Seriously fell ill after believed" The Rules of ten seconds. " Between these two works, an advertisement for chocolate dragees M & M’s, who beat the popular performance:

https://www.youtube.com/watch?v=lg8rfo_u_pq

When the distribution of the “Rules of N seconds” became widespread, representatives of science became interested in the issue.

In 2003, Gillian Clark, a student of the Chicago Higher School of Agricultural Sciences, published The results of his research on the topic "Rules of five seconds". Clark threw on ceramic tiles pre -treated with samples of E. coli, marmalade bears and cookies. Checking using a microscope showed that Escherichia Coli bacteria came to foods definitely faster than five seconds. In addition, Clark conducted a public opinion poll, which showed that 70% of women and 56% of men are familiar with the rule and the majority is guided by them, deciding whether there is food raised from the floor. In 2004, Clark's study was noted Ignobel Prize in the field of healthcare.

In 2006, Paul Dawson already mentioned above investigated The vitality of Salmonella Typhimurium bacteria on the flooring and the likelihood of its subsequent transmission in contact with the sausage or bread. The results were disappointing: a) Salmonella can live on such surfaces up to four weeks; b) During contact, it is transferred to food almost instantly.

Another relatively recent study showedthat the number of bacteria entering food still depends both on the type of food or type of surface, and on time. However, at the same time, the time sufficient to transmit a potential dangerous number of bacteria was very often insignificant.

To reduce potential risk, microbiologist Philip Tirno in his book "Secret life of bacteria" Recommends to use strictly different shoes at home and on the street. However, this precaution may not be enough, if not remembered once and for all: there is no “rules of five seconds” in real nature. Moms and dads prohibiting children to take food from the floor are absolutely right.