Although up to 20% of the population claims to suffer from some of the most well-known food allergies, the reality is that only half of them suffer from them.
Although many individuals claim to have food allergies, the reality is that it is not usually common. If a group of individuals were asked in a survey how many know or think they know that they suffer from a food allergy, approximately 20% of them would affirm it. And yet half of them would be wrong.
At least in the United States, a country with more than 300 million inhabitants, only 1 in 10 individuals actually suffers from any of the currently known food allergies, according to new work published in JAMA Network Open, where more than 40,000 individuals were analyzed in all the country.
Food Allergies or Intolerances: Important Differences
According to this new research, up to 19% of those surveyed stated without question that they were allergic to certain foods, but did not experience the typical physical reactions associated with common food allergies. This does not mean that food allergies are a mental invention, far from it, but rather a misconception on the part of the general population.
A food allergy can be life threatening, and not knowing how to recognize its risks and self-diagnose without consulting a medical professional can be misleading, as the authors well recall in their work.
According to the same researchers, led by Dr. Ruchi Gupta, a pediatrician and professor of pediatrics at Northwestern University School of Medicine, it is likely that these individuals experienced signs of food intolerances or other food- related conditions, and not food allergies to use.
Within allergies, there is an immune system response to a trigger that is perceived as a threat, although it is not. Specifically, in food allergies, the most common being allergies to nuts, legumes, eggs or shellfish, a multitude of reactions can occur that can vary between individuals, according to the Centers for Disease Control and Prevention of the United States (CDC).
In both a normal allergic reaction and in the case of food allergies it is possible to suffer symptoms such as hives, itching, swelling of the nose or throat, and nausea, vomiting and / or stomach pain. In severe allergic reactions, it is possible to reach anaphylaxis, a state of shock where there is a serious decrease in blood pressure and a sudden closure of the airways, being the case potentially fatal.
In the case of the United States, the most common allergenic substance (affecting 7 million individuals) is shellfish, followed by milk (5 million individuals) and peanuts (5 million individuals). Other known allergens include tree nuts, fish, eggs, wheat, soybeans and sesame, according to the researchers.
On the other hand, the case of inherited or acquired allergies stands out, such as the strange case of the allergy to red meat caused by a tick bite, or the case of the farmer who ended up developing an allergy to onion skin after a whole life exposed to them. Although these are peculiar cases, it is not uncommon to develop an allergy in adulthood, according to the researchers: 48% of the individuals with real allergies cataloged in this work developed them in adulthood, and not in childhood as is often thought.
Lactose and gluten: Intolerances are not food allergies
Although a milk allergy really does exist, lactose intolerance, a totally different digestive reaction, is much more common.
In lactose intolerance, this "sugar" (a disaccharide) is not properly digested by the large intestine, releasing waste substances such as methane and some acids, which will consequently lead to the typical symptoms of abdominal pain, bloating, spasms, nausea, vomiting and especially diarrhea. It is currently speculated that up to 70% of the population could suffer from this intolerance, especially in the cases of adults of Asian, African or Native American origin.
To diagnose lactose intolerance, a test called the hydrogen breath test can be performed, which quantifies the presence of hydrogen, one of the wastes of lactose. However, it is more common to try to remove lactose products from the diet and test tolerance without testing.
In the case of milk allergy, there is an allergy to cow's milk proteins (PLV), and not to lactose as such. Symptoms usually begin in the first three years of life and can disappear after four years. The symptoms are similar to a lactose intolerance, but with the added factor of possible anaphylaxis after consuming milk, as we have already mentioned.
For its part, there is gluten, within which we can differentiate allergy, intolerance and "sensitivity" to gluten (the latter currently very controversial).
Within the allergy, there is no clear allergy to gluten per se, but rather an allergy to wheat (easily confused with gluten intolerance or celiac disease), within which it is possible to suffer allergic symptoms and even anaphylaxis as already we have commented. In this case, it is possible to consume the rest of cereals, some of which do contain gluten. If you are gluten intolerant, this would not be possible.
In the case of gluten intolerance or celiac disease, the immune system attacks the lining of the small intestine when it comes in contact with a food containing gluten, a protein found in many types of cereals. Although it only affects 1% of the population, currently up to 12% of individuals claim to suffer some level of intolerance to this protein. It is what is currently known as gluten sensitivity. In the case of intolerance or celiac disease, the symptoms are similar to lactose intolerance, but its diagnosis is more protocolized, and signs can be detected in a blood test or by performing intestinal biopsies. The treatment, as in the case of lactose, is to stop eating foods with gluten.
Finally, gluten sensitivity is a controversial case, and there are studies that claim that it is a " brain hoax ", since it was shown that some individuals suffer abdominal pain, bloating, nausea and diarrhea consuming gluten-free foods, when they believed it did contain gluten. It is the so-called nocebo effect, or a situation where health deteriorates just because we have expectations that we can get worse.
On the other hand, more recent studies affirm that there would be another factor to take into account within this sensitivity to gluten: fructans, molecules present in wheat, but also in other foods that do not contain gluten but do cause gastrointestinal symptoms in certain individuals who they self-diagnose as "gluten sensitive". At the moment, it is a possible variant of celiac disease, but there is still a lot of research to be done on it.