Most textbooks contain health-related messages. However,one in four messages is not based on any scientific evidence such as “breathing through the nose instead of through the mouth prevents colds”, according to an investigation by the Hospital de Baza (Granada) published by the magazineBMC Public Health. “We analyzed a total of 844 health messages in primary and secondary education textbooks to identify the level of scientific evidence on which these texts are based and classified them into three categories: messages with a high, medium or low level of evidence; messages with an unknown level of evidence or messages with no known evidence “, explains Inés Mª Barrio Cantalejo, lead author of the study.
Of the 80 books used in the sample, 73.7% (59 books) were elementary school and contained 548 messages. The average number of messages per book amounted to 10.6 and the highest concentrations of health content were found in the third year of secondary school (37%) and, by subject, in the subject of Biology and Geology (32.5% ).
Of the total of 844 messages studied, 61% were classified with an unknown level of evidence and 15% corresponded to the category in which the level of scientific certainty is known. However,24.6% did not show any known evidence(statements such as “breathing through the nose instead of through the mouth prevents colds” or “after eating do not swim, the digestive process can be altered and you may suffer a digestion cut”). What’s more,two messages went against scientific reality: “in the event of a muscle injury, you must always rest” and “you must disinfect the wounds with hydrogen peroxide”?.
By topic, more than 70% of the messages related to “balanced diets and malnutrition”, “food hygiene”, “tobacco”, “sexual behavior and AIDS” and “rest and ergonomics” were based on an unknown level of evidence. The“oral health” registers the highest percentage of messages based on a high level of certainty (37.5%), followed by “pregnancy and newborn babies” (35%).
