Digestive problems are one of the most frequent consultations in pediatrics, but in the case of autism , they are almost a constant, and many of these digestive problems , which in many cases have a sensory origin, generate behavioral problems , but are normally resolved. It addresses behavior on the one hand and digestive problems on the other, as if they were two different entities, in this way, incredibly, neither of them is resolved, and these tend to be persistent for life in people with greater support needs.

Again, digestive problems in autism are profusely documented , with food selectivity being one of the biggest visible problems that children present and that have a strong relationship with sensory aspects, which later turns into neophobia or panic about trying new foods, eating ultra-fast or incredibly slow, chewing problems, etc., are closely linked to problems of constipation , retching, vomiting, abdominal pain, skin problems, sleep problems , irritability, and a long list of problems associated with digestive system problems , and this is also linked to microbiota or intestinal flora problems.

In a study published in January 2020, it was observed that 84.6% of children ^{​18​ present} selective feeding and rejection of new foods, this is a very alarming fact, since no intervention is carried out on feeding problems at 84 .6% of children. But 49.3% engage in “food theft” behavior, with the intention of eating only what does not generate negative experiences.

It was found that overall 82.4% of participants experienced at least one gastrointestinal symptom in the last 3 months; 22.8% presented only one symptom, and 22.8% presented two symptoms; 22.1% of the participants presented three symptoms, while 12.5% ​​and 2.2% presented four and five symptoms respectively.

Research reveals that children and adolescents with autism with digestive system problems comorbidly present challenging behaviors and greater sensory problems.

Another study published in November 2019 ^{looked at} whether there were differences in young children with digestive problems between those who had verbal communication and those who did not, to evaluate whether communication problems could be involved in the greater severity of these problems. The result was negative, they practically obtained the same data in both groups, although they presented the usual list of symptoms, such as sleep problems, behavioral problems, anxiety, irritability, etc., this comes to the hypothesis that perhaps, the problems interoceptives make it difficult to correctly identify the discomfort or pain that the boy or girl may present. Let us not forget the testimonies of many adults who claim not to be able to feel a sensation of hunger or satiety, for example, or many children who are not aware of the bodily sensations linked to defecating and urinating, an aspect that in turn also generates another long list of problems.

What is obvious is that abdominal pain, gastroesophageal reflux, diarrhea, constipation, and the entire long list of digestive ailments generate discomfort, and that discomfort directly causes a behavioral manifestation, especially in those who are not able to communicate that physical discomfort, or , those who also do not know how to correctly identify that physical discomfort due to problems in interoception .

Hippocrates stated that “ Every disease begins in the intestine .” However, despite Hippocrates' statement, today we do not know for sure what the real trigger is, if there is a genetic factor that influences the alteration of our internal biochemistry, if there is an abnormal functioning of certain organs, If it is the eating disorder itself that causes poor development of our digestive system, honestly, it is like wondering which came first, the chicken or the egg. I don't really know what or who is the real cause, if it is a hormone that is not produced or processed, if it is a problem linked to our intestinal flora, if it has a sensory origin, if there are motor aspects involved (swallowing problems), if There are psychological factors (traumas), or if it is perhaps a set of all of them at the same time, in addition, there are differences between children, so the variables that must be analyzed are immense.

Among the multiple causes attributed to autism, which more than causes are actually factors that increase the probability, we have leptin, or an alteration in it, a 2018 study ^{​21​ analyzed} leptin levels in the umbilical cord and then In fact, there is some evidence that links rapid weight gain in babies to the likelihood of autism , and leptin appears to be involved in this process.

But what is leptin? It is a hormone produced by adipocytes, or fat cells. In fact, this is an example where the brain is controlled by that chemical game produced by parts of our body, high levels or low levels of leptin in the body impact the feeling of hunger, that is, fat cells emit a lot of leptin when The amount of fat stored is sufficient, so that they send a signal to the brain to inhibit the feeling of hunger. Interestingly, obese people have high concentrations of leptin, but the leptin receptors that give the “I'm full” signal do not seem to function properly.

Well, this study was carried out on a sample and follow-up of 822 subjects from the Boston Birth Cohort, they discovered that those who gained weight very quickly in infancy had higher leptin levels in early childhood and a greater probability subsequent diagnosis of autism. They followed them for 5.2 to 9.8 years to see how many of them received a diagnosis of autism or other neurodevelopmental conditions.

That is, an alteration in leptin levels in the umbilical cord blood is a risk indicator for autism. Remember, a risk indicator does not imply an absolute issue, but rather the probability increases. In fact, other recent studies ^{​22​ also report} that alterations in leptin, among others, may be related to neurodevelopmental disorders, including IL-6 (interleukin) and other chemical messengers, many of them involved in the regulation of the immune system. immune. And that immune system, as we have seen, has a great relationship with our digestive system.

Another factor that is becoming more relevant every day is alterations in the intestinal microbiota. It is not clear whether these alterations are cause or effect, or even both, effect of and causes of. We do know that alterations in the microbiota are related to certain conditions of food intolerance and allergies, which directly affects the immune system, and obviously affects a multitude of functions in our body.

There are associated genetic factors, but this part of the research is still very recent, and there are hardly any studies related to this particular aspect, little evidence, so we continue in the field of hypothesis. A German study ^{​23​ addressed} this aspect related to Haploinsufficiency linked to the FOXP1 gene in a study in mice. This genetic factor seems to be linked (among other things ) to a pronounced atrophy of the muscular tunic in the esophagus and colon, accompanied by motor dysfunction, an aspect that directly involves problems in the digestive system, although this type of research has yet to be carried out. at an early stage in order to draw more solid conclusions.

Cristina Oroz bass

Extracted from Autism Diary