Food allergies are due to IgE antibodies made to specific foods that an individual has developed for some reason because their body has misinterpreted the food as a foreign invasive protein. The presence of IgE antibodies against the specific food a person is allergic to results in an immediate immune reaction of the body to the food when it is ingested. The IgE antibody binds to its specific food protein and initiates reactions in the body that include the release of chemicals such as histamine that can cause symptoms of itching, swelling, wheezing or shortness of breath, rash or hives and, if severe, a shock that causes death. if not reversed. Vomiting and diarrhea can occur, but are less common.
Testing for the presence of a food or food allergy can be done using blood tests, skin tests, or both. One of the most common blood tests is the RAST test that looks for the presence of specific IgE antibodies to common food allergens and other foods based on a history that suggests a particular food is suspect. Skin tests are performed by injecting or applying extracts of the common food and any suspicious foods into the pitted or scraped skin and looking for “hive” -like diagnostic reactions at the site of the suspect food. The most common food allergens are peanuts, cow’s milk, wheat, corn, soybeans, shellfish, eggs, nuts, chocolate, pork, tomatoes, and citrus fruits.
The terms food intolerance and sensitivity are commonly used interchangeably. They refer to a group of reactions to foods that occur and are not caused by IgE antibodies. More generally, they refer to any adverse or unpleasant reaction that occurs after eating a food.
Non-allergic reactions to foods can have a variety of causes. A particular food may not be tolerated because it is not digested properly due to a deficiency of enzymes. Lactase, the enzyme that digests milk sugar or lactose, is present on the surface of the cells that line the intestine. Lactase deficiency can be inherited or acquired. It commonly occurs when the lining of the intestine is damaged. Because lactase enzymes are found on the outermost surface of the intestine, they are more vulnerable to injury. For example, after the intestinal flu or in untreated celiac disease, lactose intolerance is common. Other sugar enzymes may be deficient, or the gut may simply be overwhelmed by too great a sugar load at one time. A classic example is the “Big Gulp” syndrome when someone drinks a giant cola drink and then experiences the “stomach ache” due to the tremendous amount of fructose. The intestine cannot handle large amounts and this causes bloating, urgency and terrible diarrhea.
The deficiency of digestive enzymes released in the intestine can result in poor digestion of food. For example, when the pancreas gland is chronically damaged (pancreatitis), usually from chronic alcohol abuse, or is congenitally underdeveloped or malfunctioning (for example, cystic fibrosis). The pancreatic enzyme deficiency that occurs results in malabsorption, especially of fats, causing symptoms of diarrhea and weight loss. Abnormal types and levels of bacteria in the gut, also known as dysbiosis, and abnormal levels in excess of “bad” bacteria or the presence of bacteria in the upper part of the small intestine, where little or no bacteria are normally produced (overgrowth bacterial) can interfere with digestion, absorption or cause. fermentation of food resulting in symptoms of abdominal pain, bloating, gas, and diarrhea.
Some foods and food additives have a direct toxic effect on the gastrointestinal tract. Additives like MSG and sulfites can cause symptoms, such as flushing and diarrhea, or “Chinese restaurant” or “salad bar” syndromes.
All foods contain proteins known as lectins. Some of these proteins are very resistant to digestion and are toxic to the human intestine, especially if they are not pre-treated by soaking, cooking well, or removing toxic portions. For example, soaked and improperly cooked kidney beans will cause food poisoning similar to illness. There are several foods that have lectins that many humans tolerate poorly and are lethal to insects and pests. A researcher, Loren Cordain PhD., Author of the Paleo Diet, has published extensive research on how the human gut is not “evolved” to tolerate many of the foods we eat now but did not eat in ancient “hunter-” times. collectors “. resulting in many of the diseases seen in modern societies and the growing epidemic of autoimmune diseases. Several of the “modern” foods that were not part of the ancient diet but that make up a large part of our diet now have toxic or poorly tolerated proteins known as lectins. Examples include wheat germ agglutinin (WGA), casein (cow’s milk protein), peanut agglutinin (PNA), soy agglutinin (SBA), and tomato lectin (TL) which have been shown in animal studies to they are toxic to the human intestine. There are some published studies and little active research on the role of dietary lectins in health and disease.
When the reaction is an immune toxicity reaction to a dietary protein, intestinal damage commonly occurs, often referred to as “leaky gut” due to symptoms of malabsorption or the entry of toxic dietary proteins and / or bacterial products into the bloodstream that results in a variety of adverse health effects. This reaction can result in autoimmunity, the body attacking itself within the intestine or distant organs or tissues. The reaction can be favored by abnormal types and / or levels of bacteria in the intestine (dysbiosis). Symptoms commonly develop over time and worsen in just a few hours to three days after eating the unhealthy food and continue as long as the food is ingested.
Because protein in food is often the cause and such proteins can be hidden in other foods, especially processed foods, and toxicity is more of a delayed and cumulative immune reaction, it is very difficult for the person suffering from this to identify the specific food as the cause. For example, gluten (the protein in wheat) and casein (the protein in cow’s milk) are found in many foods and are toxic to many people. Over time, people sensitive to these food proteins tend to become more ill and may develop enough intestinal damage that blood tests for other types of antibodies, IgG and / or IgA, to specific foods or food proteins, can be detected in the blood, feces, or feces. saliva.
Delayed immune response to proteins in food (wheat, cow’s milk) resulting in intestinal lesions, gastrointestinal and non-gastrointestinal symptoms, and increased autoimmune conditions, is better recognized in celiac disease. It is an autoimmune disease resulting from the ingestion of gluten in wheat or products made from wheat flour (or gluten-like proteins in barley and rye). It used to be considered a children’s disease and rare, especially in the United States. However, blood test screening studies have documented that it is present in about 1 in 133 to 1 in 100 people worldwide, although most of those affected are not diagnosed or treated. It is diagnosed by positive screening blood tests and confirmed by a characteristic abnormal small intestine biopsy, followed by relief of symptoms and return of the intestine to normal after a gluten-free diet. If left untreated, it is associated with higher rates of cancer, especially lymphoma, osteoporosis, anemia, and other complications of malabsorption, reducing life expectancy. It is treated with a gluten-free diet for life. Minor degrees of gluten intolerance or sensitivity may not be severe enough to cause abnormal or diagnostic blood tests and intestinal biopsies, but result in symptoms that improve or resolve on a gluten-free diet and can be detected by testing raised antibodies in stool or saliva.
Although injury to bowel tissue can be visually seen as abnormal-appearing tissue during endoscopic procedures, these findings are not specific to the cause. Often the tissue appears normal and therefore biopsy samples are often not taken, although a lesion can be seen under the microscope, although it is not specific to cause or food. If the doctor does not suspect a food intolerance or does not routinely biopsy normal-appearing intestinal tissue for signs of food intolerance, the lesion may not be discovered.
Immune-based food intolerances are commonly associated with many symptoms that can be both gastrointestinal and outside of the gut and can include bloating, gas, diarrhea (and sometimes constipation), abdominal pain, nausea, fatigue, headaches, joint and muscle aches , rashes. , weight gain or loss, anemia or nutritional deficiencies, irritability, depression, mental confusion, and nerve pain (neuropathy). These symptoms can be misdiagnosed or mislabeled as irritable bowel syndrome, chronic fatigue syndrome, reflux, ulcer, and fibromyalgia, etc. without the patient or doctor thinking that food intolerance may be the cause and eliminating specific foods may be the cure. Common food allergens are also the most common causes of food intolerance reactions.
In general, most doctors know the common symptoms of food allergies and how and when to test. However, several studies have confirmed the experience of most people that the common symptoms of celiac disease are unknown to most primary care physicians, that blood tests are available for antibodies and high-risk genes, and that it is common and can be diagnosed in adults. . This is why the diagnosis is delayed on average more than 11 years in most adults, after many of them have irreversible complications such as osteoporosis, cancer or another autoimmune disease. The awareness and acceptance of non-celiac gluten sensitivity and other food protein intolerances in the medical community is even worse.
Therefore, food intolerance or sensitivity is commonly overlooked and left untreated. Many patients are forced to self-diagnose by fortuitously discovering the link of their symptoms to specific foods, often as a result of an elimination diet, recommendation from an alternative doctor or friend / relative, or seeking help online or from multiple doctors. . for help. Hopefully, by reading this article, you will have a better understanding of food allergies and intolerances, why they are often overlooked and that they are a common cause of many symptoms, not just intestinal, that generally improve, if not resolved, once the foods that cause the damage are removed. your diet.
