Food allergy is an abnormal response to a food, triggered by the body’s immune system. A food allergy occurs when the immune system responds to a harmless food as if it were a threat. The first time a person with food allergy is exposed to the food, no symptoms occur. But the body has been now been primed, and when the person eats the food again, an allergic response occurs. It can be life threatening and can lead to Anaphylaxis.
An allergic reaction to food usually takes place within a few minutes to several hours after exposure to the allergen. The process of eating and digesting food and the location of immune cells involved in the allergic reaction process both affect the timing and location of the reaction.
The most common type is of adverse reaction to food, in which the body produces a specific type of antibody, called immunoglobulin E (IgE).
Allergic reaction process
An allergic reaction to food is a two-step process:
The first time you are exposed to a food allergen, your immune system makes specific immunoglobulin E (IgE) antibodies to that allergen. IgE antibodies circulate through your blood and attach to types of immune cells called mast cells and basophils. Mast cells are found in all body tissues, especially in your nose, throat, lungs, skin, and gastrointestinal (GI) tract. Basophils are found in your blood and also in tissues that have become inflamed because of an allergic reaction.
The next time you are exposed to the same food allergen, the allergen binds to the IgE antibodies that are attached to the mast cells and basophils. The binding signals the cells to release massive amounts of chemicals such as histamine.
Depending on the tissue in which they are released, these chemicals will cause you to have various symptoms of food allergy. The symptoms can range from mild to severe. A severe allergic reaction can include a potentially life-threatening reaction called anaphylaxis.
Generally, you are at greater risk for developing a food allergy if you come from a family in which allergies—including food allergies and other allergic diseases such as asthma or eczema—are common. Having two parents who have allergies makes you more likely to develop food allergy than someone with one parent who has allergies.
Symptoms of food allergy
If you are allergic to a particular food, you may experience some or all of the following symptoms:
- Itching in your mouth or swelling
- GI symptoms, such as vomiting, diarrhea, or abdominal cramps and pain
- Hives or eczema
- Tightening of the throat and trouble breathing
- Drop in blood pressure
First exposure to food
Usually, you are first exposed to a food when you eat it, but sometimes a first exposure or subsequent exposure can occur without your knowledge.
This may be true in the case of peanut allergy. A person who experiences anaphylaxis on the first known exposure to peanut may have previously had contact with peanuts in any of the following ways:
- Touching peanuts
- Using a peanut-containing skin care product
- Breathing in peanut dust in the home or when close to other people eating peanuts
Cross-reactive food allergies
If you have a life-threatening reaction to a certain food, you must avoid similar foods that may trigger this reaction For example, if you have a history of allergy to shrimp, allergy testing may show that you are also allergic to other shellfish, such as crab, lobster, and crayfish. This is called cross-reactivity.
Eosinophilic Esophagitis and Food Allergy
Eosinophils from human peripheral blood, mouse bone marrow, and mouse bone marrow culture
Eosinophilic esophagitis (EoE) is a newly recognized chronic disease that can be associated with food allergies. It is increasingly being diagnosed in children and adults. EoE is characterized by inflammation and accumulation of a specific type of immune cell, called an eosinophil, in the esophagus.
Symptoms of EoE include nausea, vomiting, and abdominal pain after eating. A person may also have symptoms that resemble acid reflux from the stomach. In older children and adults, it can cause more severe symptoms, such as difficulty swallowing solid food or solid food sticking in the esophagus for more than a few minutes. In infants, this disease may be associated with failure to thrive.
Oral allergy syndrome
Oral allergy syndrome (OAS) is an allergy to certain raw fruits and vegetables, such as apples, cherries, kiwis, celery, tomatoes, and green peppers. OAS occurs mostly in people with hay fever, especially spring hay fever due to birch pollen and late spring hay fever due to ragweed pollen (“ phuler renu”).
Eating the raw food causes an itchy, tingling sensation in the mouth, lips, and throat. It can also cause swelling of the lips, tongue, and throat; watery, itchy eyes; runny nose; and sneezing. Just handling the raw fruit or vegetable may cause a rash, itching, or swelling where the juice touches the skin.
Cooking or processing easily breaks down the proteins in the fruits and vegetables that cause OAS. Therefore, OAS typically does not occur with cooked or baked fruits and vegetables or processed fruits.
What Is Anaphylaxis?
If you have a food allergy, there is a chance that you may experience a severe form of allergic reaction known as anaphylaxis. Anaphylaxis may begin suddenly and may lead to death if not immediately treated. Anaphylaxis is a severe, potentially life-threatening allergic reaction. Symptoms can affect several areas of the body, including breathing and blood circulation.
Anaphylaxis includes a wide range of symptoms that can occur in many combinations. Some symptoms are not life-threatening, but the most severe restrict breathing and blood circulation.
Many different parts of your body can be affected:
- Skin—itching, hives, redness, swelling
- Nose—sneezing, stuffy nose, runny nose
- Mouth—itching, swelling of lips or tongue
- Throat—itching, tightness, difficulty swallowing, hoarseness
- Chest—shortness of breath, cough, wheeze, chest pain, tightness
- Heart—weak pulse, passing out, shock
- Gastrointestinal (GI) tract—vomiting, diarrhea, cramps
- Nervous system—dizziness or fainting
How soon after exposure will symptoms occur?
Symptoms may begin within several minutes to several hours after exposure to the food. Sometimes the symptoms go away, only to return two to four hours later or even as many as eight hours later. When you begin to experience symptoms, seek immediate medical attention because anaphylaxis can be life-threatening.
Can anaphylaxis be predicted?
Anaphylaxis caused by an allergic reaction to a certain food is highly unpredictable. The severity of a given attack does not predict the severity of subsequent attacks. The response will vary depending on several factors, such as the following:
- Your sensitivity to the food
- How much of the food you are exposed to
- How the food entered your body
Any anaphylactic reaction may become dangerous and must be evaluated immediately by a healthcare professional.
What can cause anaphylaxis?
Food allergy is the leading cause of anaphylaxis; however, medications, insect stings, and latex can also cause an allergic reaction that leads to anaphylaxis.
How do you know if a person is having an anaphylactic reaction?
Anaphylaxis is highly likely if at least one of the following three conditions occurs:
- Within minutes or several hours of the onset of an illness, a person has skin symptoms (redness, itching, hives) or swollen lips and either difficulty breathing or a drop in blood pressure
- A person was exposed to an allergen likely to cause an allergic reaction and, within minutes or several hours, two or more of the following symptoms occur:
- Skin symptoms or swollen lips
- Difficulty breathing
- A drop in blood pressure
- GI symptoms such as vomiting, diarrhea, or cramping
- A person exposed to an allergen that is previously known to cause an allergic reaction in that person experiences a drop in blood pressure.
Food allergy and Food Intolerance
The difference between an allergy and an intolerance is how the body handles the offending food; that is, whether the reaction involves the immune system or not. With a true food allergy, the body’s immune system recognizes an allergen as foreign and produces antibodies to halt the “invasion.” The most common battlefields are the mouth (swelling of the lips), digestive tract (stomach cramps, vomiting, diarrhea), skin (hives, rashes, or eczema), and the airways (wheezing or breathing).
Food intolerance is much more common than allergy. The problem is not with the body’s immune system, but rather with its ability to process certain compounds — hence the diarrhea and vomiting . For example ,patients are often deficient in the intestinal enzyme lactase, which is needed to digest milk sugar and have severe abdominal bloating and diarrhea on ingestion of milk.
Lactose is a sugar found in milk and most milk products.Lactase is an enzyme in the lining of the gut that breaks down or digests lactose. Lactose intolerance occurs when lactase is missing. Instead of the enzyme breaking down the sugar, bacteria in the gut break it down, which forms gas, which in turn causes symptoms of bloating, abdominal pain, and sometimes diarrhea.
Lactose intolerance is uncommon in babies and young children under the age of 5 years. Because lactase levels decline as people get older, lactose intolerance becomes more common with age.
Another type of food intolerance is a reaction to certain products that are added to food to enhance taste, add color, or protect against the growth of microbes. Compounds such as monosodium glutamate (aginamoto) and sulfites are tied to reactions that can be confused with food allergy.
- MSG is a flavor enhancer. When taken in large amounts, it can cause some of the following:
- Sensations of warmth
- Chest discomfort
These passing reactions occur rapidly after eating large amounts of food to which MSG has been added.
- Sulfites are found in food for several reasons:
- They have been added to increase crispness or prevent mold growth.
- They occur naturally in the food.
- They have been generated during the winemaking process.
Sulfites can cause breathing problems in people with asthma.
Gluten is a part of wheat, barley, and rye. Gluten intolerance is associated with celiac disease, also called gluten-sensitive enteropathy. This disease develops when the immune system responds abnormally to gluten. This abnormal response does not involve IgE antibody and is not considered a food allergy.
Some of the symptoms of food allergy, such as abdominal cramping, are common to food poisoning. However, food poisoning is caused by microbes, such as bacteria, and bacterial products, such as toxins, that can contaminate meats and dairy products.
Fish, such as tuna and mackerel that are not refrigerated properly and become contaminated by bacteria, may contain very high levels of histamine. A person who eats such fish may show symptoms that are similar to food allergy. However, this reaction is not a true allergic reaction. Instead, the reaction is called histamine toxicity or scombroid food poisoning.
In infants and children, the most common foods that cause allergic reactions are the following:
- Tree nuts such as walnuts
- Soy (primarily in infants)
In adults, the most common foods that cause allergic reactions are the following:
- Shellfish such as shrimp, crayfish, lobster, and crab
- Tree nuts
- Fish such as salmon ..
- Low intake of dietary antioxidants and exposure to cigarette smoke and other environmental pollutants are also strong indicators of increased allergy risk.
- Other potential factors which may increase allergy risk include low gastric acid secretion (known as hypochlorhydria) and intestinal overgrowth of yeast (Candida albicans).
- Peanuts are a common food allergen and should be avoided, along with peanut butter.
- Canola oil (rapeseed) may be potent allergen.
- Consumption of mucous producing foods, ie. animal by-products (milk, butter, yogurt, etc.)
- Excess consumption of any food, This variable is determined by the individual’s current detox function.
- Glutan sensitive foods based on wheat (not everyone has this issue).
- Deadly Nightshade plants (tomatoes, egg plant, potatoes) ,minority suffer from this sensitivity.
- Excitotoxins (most sugar replacements except stevia, Agave nectar, etc.).
- Incomplete foods or Non-whole foods.
- Omega-6 fatty acid may intensify inflammation. Most people in our society need more Omega-3 fatty acids and less Omega-6 fatty acids. Foods high in Omega-6 fatty acids include cottonseed, corn, and sunflower oils, as well as processed foods like mayonnaise, salad dressing, and fast food.
- Saturated fats and trans fats also trigger the release of inflammatory chemicals.
- Avoid anything that contains partially hydrogenated oil.
Food allergies generally develop early in life but can develop at any age. Children usually outgrow their egg, milk, and soy allergies, but people who develop allergies as adults usually have their allergies for life. Children generally do not outgrow their allergy to peanut.
Milk Allergy in Infants and Children
Allergy to cow’s milk is common in infants and young children and can develop within days to months of birth. The symptoms include abdominal pain, hives, and eczema, and these symptoms are typically associated with immunoglobulin E (IgE) antibodies to milk. Because abdominal pain is also a symptom of lactose intolerance, only your healthcare professional can determine if your baby’s symptoms are caused by an allergic reaction to cow’s milk.
In other children, cow’s milk can lead to colic and sleeplessness, as well as blood in the stool and poor growth. This type of reaction to milk is associated with immune responses that are not related to IgE antibody.
How Foods Fight Allergies
A nutritious diet can help control underlying inflammation, dilate air passages, and thin mucus in the lungs.There are many naturally-occurring plant compounds called phytonutrients that assist with allergies. The main ones include: anthocyanin, curcumin, hesperetin, and quercetin in your diet. Don’t worry about remembering their names. The list of foods below have them adequately .But please remember listed the food sources of each below, if you have a food allergy or sensitivity to one of the sources indicated, avoid that food.
Eat Foods Rich in Anthocyanins
The phytonutrient group known as anthocyanins give foods their purplish-red color. They have natural anti-inflammatory properties. Anthocyanins are found in most dark red and purple-colored foods. Some food sources include: beets, berries, cherries, and dark purple and red grapes.
Eat Curries to Benefit from Anti-Inflammatory Curcumin
Turmeric (Curcuma longa) ,commonly found in Indian curries, contains the active ingredient curcumin, which is a powerful antioxidant and anti-inflammatory substance. Ingesting 1200 mg of curcumin daily can have the same effect as anti-inflammatory drugs. Just add fresh or dried turmeric to many foods: soups, curries & stews. But avoid mixing curd or other dairy-based curries with turmeric or you’ll be undermining many of the anti-inflammatory benefits of turmeric since dairy products are mucous-forming.
Hesperetin/Hesperidin for Hay Fever
Hesperetin and hesperidin are potent phytonutrients have antioxidant, anti-inflammatory, anticarcinogenic, and cholesterol-lowering actions, and also protect blood vessels against damage. Hesperidin is also beneficial for allergies and hay fever because of its antihistamine properties. Green vegetables are a source of hesperidin / hesperetin. You can also find them in their highest concentration in citrus fruits like lime and oranges, especially the white part, or pith. Of course, avoid citrus fruits if you suspect that you are sensitive to them.
Take Quercetin to Quell Allergy Symptoms
Quercetin is an antioxidant, anti-inflammatory, and anti-histamine phytonutrientwith ability to improve lung function.
Apples and onions and garlic are excellent sources of quercetin. Some studies show that people who eat a lot of apples have improved lung function and reduced risk of lung conditions. Other good sources include: berries, cabbage, cauliflower, nuts (not peanuts), and black, green, or white tea.
It is frequently beneficial to take quercetin in a supplement form to assist with the histamine-induced sinus congestion, runny eyes or nose, or other allergy symptoms. Most people find relief from taking 400 milligrams of quercetin twice daily.
Omega-3 Fatty Acids
Omega-3 essential fatty acids contain eicosapentaenoic acid (EPA), which is a natural anti-inflammatory. Good sources of Omega-3 fatty acids include oily and cold water fished like salmon cod and hilsa . Another essential acid, gamma-linolenic acid (GLA), also acts as an anti-inflammatory, and it can be found in evening primrose oil, borage oil, and black currant seed oil. . Alpha-linolenic acid (ALA), is found in vegetable oils such as soyabean, rapeseed (canola), wheat germ oil, flaxseed and walnuts. ALA is also found in some green vegetables, such as Brussels sprouts, kale, spinach, and salad greens.
Fruit juices are rich sources of antioxidants that help reduce inflammation, but read the label to make sure that it’s real juice and not a bottle of corn syrup. Eat more fresh fruits and vegetables to get more antioxidants in your diet. Berries have especially high levels of antioxidants.
A high-fiber diet makes for a healthy colon. A low-fiber diet produces a lazy colon that’s more susceptible to disease. High-fiber foods like whole grains, nuts, and seeds stimulate movement in the colon and encourage the growth of “good” bacteria. In an unhealthy colon, “bad” bacteria and fungal organisms like candida may take over, which could lead to leaky gut syndrome. Leaky gut syndrome often leads to food allergies and chemical sensitivitie
Yogurt & Kefir
Another way to increase the number of good bacteria in your gut is to eat them directly. Yogurt and kefir contain live bacterial cultures. In one University of California study, allergic symptoms declined by 90 percent when patients were fed 18 to 24 ounces of yogurt a day. If you’re trying to avoid dairy products, opt for a probiotic supplement.
Some studies have shown that people who have asthma are deficient in magnesium. Foods rich in magnesium include spinash, beans, sunflower seeds, tofu, artichokes, and peas.
Other studies have shown that people with asthma are deficient in zinc. Foods rich in zinc include curd and yogurt , tofu, l oysters, crab, and chicken.
Another recent study showed that mothers who eat apples during pregnancy have a significantly reduced risk of their children developing asthma,
Parsley inhibits the secretion of allergy-inducing histamine. So add it to your bowl of salad vegetables.
There’s nothing like a warm bowl of soup when you’re feeling sick. This soup recipewill help you naturally battle allergies.
Boil an onion (with skin) and a clove of garlic. Add half a cup chopped leaves of basil and mint . After boiling for about 5 minutes, add a cup of diced tomato deseeded ,nettle leaves and a cup of diced celery stalks, and boil gently for another 3 to 10 minutes. Before eating, remove the onion skins and eat the soup it’s while still warm. Season black pepper, hot pepper and turmeric. Enjoy!
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