As per the  Food Allergy Research & Education, in the US, each year, around 200,000 people require emergency medical care for allergic reactions to food. Food allergy is a specific immune response to certain food items that it considers harmful. 

Upon exposure to the food allergen, the IgE antibodies alert cells to release powerful substances, such as histamine, that in turn give rise to different symptoms in the body. The symptoms of food allergy vary from person to person and can also differ over time. They can occur anywhere in the body but most commonly affects the skin, cardiovascular system, the gastrointestinal and respiratory tract and sometimes lead to anaphylaxis, a life-threatening reaction that results in rash, low pulse, and shock. Developed within a few hours of consumption, the most common symptoms include nausea, vomiting, itching in the mouth, wheezing, cough, diarrhea, and abdominal pain, etc. 

Food allergy often affects the quality of life and can also lead to an adverse health effect. For people allergic to particular food items, even the intake of a minimal quantity of food can lead to severe reactions. Food allergy is usually diagnosed during childhood; however, the allergy can also appear in the later phase of life. While children generally outgrow allergies, it is difficult for adults to outgrow these allergic reactions.  

What are the most common food allergies?

As per the  FARE, in the USA, around 32 million people are living with potentially life-threatening food allergies. More than 170 food items are supposed to cause allergic reactions; however, eight major allergens account for about 90% of food allergy reactions, which includes- 

Egg Allergy

Egg allergies are the most common food allergy in children. As per the ACAAI, around 2 percent of children are allergic to eggs, and about 70 percent of children with an egg allergy will outgrow the condition by age 16. 

The most common symptoms of egg allergy include Vomiting, Stomach Cramps, Indigestion, Nasal Congestion, Coughing, and Wheezing. The age and the family history of the person are the primary risk factors for egg allergy.

Milk Allergy 

Occurring most commonly in infants and young children, the milk allergy is an abnormal response by the body’s immune system to the milk products. Young children require vitamins and minerals like calcium for the growth and development  The milk allergy can lead to mild to severe symptoms in the affected person. The typical sign of the milk allergy includes Hives, Coughing, Stomach upset, Itching, Vomiting, Bloody stools, and many others. In some cases, it can also cause Anaphylaxis.  Avoiding milk products is the best way to avoid allergic reactions. 

Peanut Allergy 

Over the past few decades, peanut allergy prevalence has increased steadily, mostly in Western countries. Peanuts allergy can lead to Vomiting, Stomach Cramps, Indigestion, Diarrhea, Wheezing, and many other symptoms. Age, past allergy to peanuts, and family members with allergies are a risk factor for the peanut allergy. 

In Jan 2020, US FDA had approved Palforzia {AR101 (Aimmune Therapeutics)}, for the treatment of peanut allergy. Palforzia is the first approved treatment for patients with peanut allergy. 

Tree Nuts Allergy

Tree Nuts consist of almonds, cashew, lychee nuts, pecans, walnut, pine nut, and many others. Peanuts are often confused with tree nuts. While peanuts are legumes (enclosed in pods), on the other hand, tree nuts are produced on trees. The allergy to tree nuts starts in childhood and can also remain lifelong. 

As per the American Academy of Allergy, Asthma & Immunology, tree nut allergy is one of the eight most common food allergies, affecting roughly 0.5 to 1% of the U.S. population. Similarly, around 25–40% of people with peanut allergies are also allergic to at least one tree nut. Family history and the allergy to one type of nut increases the risk for other nuts allergies. 

Fish Allergy 

Fish allergy is usually a lifelong allergy that mostly develops in adulthood. Around 40% of people experience a fish allergy as an adult. Fish allergy can cause symptoms such as Nausea, Stomach cramps, Indigestion, Vomiting, Diarrhea, Headaches, and many others. Avoiding fish and fish products such as fish gelatin, fish oil, and sticks are the best options to prevent fish allergy. 

Shellfish Allergy

Upon exposure to protein in certain marine animals, the body’s immune system develops allergic reactions. Shellfish allergies are caused by two groups of marine animals known as Crustaceans and Mollusk. The allergic reactions from Crustaceans are more common than Mollusk. 

The allergic reactions can create mild symptoms such as Itching, Hives, Eczema, and sometimes can also lead to a  potentially life-threatening condition such as Anaphylaxis. The shellfish allergy can occur at any age; however, it is most common in adults as compared to children.  

Wheat Allergy 

As the name suggests, wheat allergy is usually triggered by the consumption of wheat products such as bread, pasta, noodles, dumplings, and many others. Family history and age are the two major risk factors that increase the risk of developing a wheat allergy. Babies and toddlers are observed to develop wheat allergy more commonly as compared to adults. As per Cianferoni A. et al., children have a higher prevalence of wheat allergies compared to adults and are more likely to develop an allergy if wheat is introduced after 6 months of life. As per the ACAAI, “wheat allergy is typically outgrown by adulthood, around 65 per cent of children with a wheat allergy will outgrow it by the time they are 12”.

Soy Allergy

Soy allergy is common in infants and young children. Usually, with age, most children outgrow the soy allergy; however, in some people, it remains lifelong. Like other food allergies, soy allergy can cause Itching, Hives, Eczema, Dizziness, Fainting, and many other reactions in the body. Family history, existing allergy to other food, and age are the risk factors for soy allergy. Avoiding soy and soy products is the first step to prevent soy allergy. 

Food allergy is a serious public health concern, especially for children. Apart from the quality of life, it also creates an imbalance in the nutritional diet balance of the person. What symptoms or reaction, a food allergy can cause is quite uncertain, which creates a psychological burden on the affected person. The risk of accidental exposure further restricts certain dietary activities and the social life of the person.

There is no cure for food allergies. However, medications such as Antihistamines and Adrenaline are used to relieve the symptoms of an allergic reaction. Antihistamines are recommended for mild to moderate allergic reactions while the adrenaline for severe allergic reactions. For peanut allergies, the FDA has approved the first treatment for children and teenagers between the ages of 4 and 17 years. Avoidance is the best way to protect oneself from an allergic reaction. The allergy passes from parent to children, for such cases, parents should routinely monitor the children’s health for any possible reactions. Reading labels, taking care while cooking or dining out, and carrying medications can reduce the chances of major allergic reactions. Today, many therapies are in research phases for different allergens. In the coming years, the launch of the expected therapies and the R&D in the cellular immune responses are expected to improve the quality of life of allergic patients and their caregivers.