Top 6 Food Allergies: Are Blood Tests Reliable

From tiny bumps on the body to a medical emergency, a food allergy can terribly affect you. Around 40% of the global population suffers from food allergies. The scary part is that many of them don’t even care to know the exact food and choose to eliminate the entire food family and avoid the allergy.

Medical science has developed many tests to determine your food allergies. Then why avoid all your favorites rather than eliminating just that pesky one?

What is an Allergy?

The adverse reaction of the human body towards a harmless environmental substance is an allergy. The reactions may range from hives, itchiness, and watery eyes to a life-threatening casualty.

The cause of this allergy is an allergen. There are different types of allergies posing minor and significant discomfort. These are-

  • Molds Allergy
  • Animal Dander Allergy
  • Dust Allergy
  • Pollen Allergy
  • Insect bite Allergy
  • Food Allergy

This article shall focus on different food allergies and the availability of blood tests to identify the allergens.

What is Food Allergy?

When one experiences an immune system reaction after consuming a miniscule amount of the allergy-causing food or allergen, it is called a food allergy. This may also happen when the body reacts to a specific protein in the food. These reactions may vary from hives, swollen airways, etc., to life-threatening conditions such as anaphylaxis.

It is to be noted that at least 8% of children below 5 years face food allergies. However, with time they outgrow the condition. Yet doctors suggest parents be vigilant towards the slightest reaction and take medical assistance when required.

What are the top 6 Food Allergies?

The best method to avoid a food allergy is eliminating the trigger food from your diet. Over the years, many researchers have listed a few food products responsible for allergies.

Below we list the top 6 foods triggering allergies.


You might have heard about many people complaining of lactose intolerance. However, allergy to milk or milk products shouldn’t be confused with intolerance. It’s because milk allergy is a lot more severe. The body may fail to recognize dairy and attack it by releasing histamines.

Histamines is a chemical found in the cells that the immune system releases on believing that a usually harmless substance has entered the body to create a stir. The histamines cause allergic symptoms by acting on the person’s eyes, nose, gastrointestinal tract, skin, lungs, etc.

Tree Nuts

Cashews, hazelnut, pecan, pistachio, almond, and walnut are highly nutritious tree nuts. However, these are also allergy-causing food products to a large population. It’s considered the most common type of food allergy in adults and children.

Tree nuts are notorious for causing severe allergic reactions, sometimes leading to death. Also, if you are allergic to one of the tree nuts, there is a high possibility of facing similar conditions with other nuts. In most cases, doctors advise staying away from all the tree nuts, regardless of the trigger product. If you face tree nut allergy, you must be vary of food products that use nut sprinkling for crunch and garnishing since a slight amount can cause severe adversities.


Though vastly considered as a tree nut, the peanut is a legume since it grows underground. However, this tasty snack can actually be deadly to those facing allergies. Even the research states that nearly half of the food allergy deaths every year are due to the peanut allergy.

The slightest intake of peanuts for those with its allergy may lead to fatalities like anaphylaxis. Because of its severity, doctors insist on carrying remedial medicines to avoid casualties.


Soy allergy isn’t common. However, those who suffer must be extra vigilant of its presence. Generally, we presume that avoiding soy sauce, tofu, and soybeans can help us stay safe.

However, soy has a massive consumption. It is used in so many food products as a binding agent. Most of the burgers, cutlets, and other fast foods we consume have an addition of soy for an added crunch. Hence, if you suspect soy allergy, inform the chef. It shall help them tweak the menu and avoid allergen.


Similar to lactose intolerance, gluten intolerance or celiac disease is also a health concern for a large population. However, the difference between gluten intolerance and lactose intolerance is that the former is chronic.

One may face wheat allergy problems while having wheat, but the other grains, such as oats, barley, etc., may be safe to consume. But intolerance shall cause severe issues during consumption of other grains too. Also, wheat allergy usually subsides, but intolerance or celiac disease may become chronic.


In the fish allergy segment, it’s the shellfish, especially the crustacean group comprising shrimps, lobster, and crabs, that most people are allergic of. Mollusks, i.e., scallops, oysters, clams, and mussels, are mostly tolerable in small doses.

Most medical practitioners ask people to avoid the entire range of fish. However, in general, some fishes are harmless. Another fact about fish allergy is that it mainly develops in adulthood, unlike other allergies that emerge during childhood.

What are the symptoms of Food Allergy?

The symptoms of a food allergy may differ from mild to severe. It’s crucial to know these and act swiftly to avoid complications. Here we enlist all the known symptoms to identify and save lives.

  • Itching in the mouth/body
  • Tingling sensation in the throat and/or mouth
  • Hives
  • Swelling of face, lips, tongue, and/or other body parts
  • Wheezing
  • Breathing issues
  • Diarrhea
  • Abdominal pain
  • Nausea
  • Dizziness
  • Fainting
  • Sensation of a lump in the throat
  • Severe drop in blood pressure
  • Rapid pulse
  • Loss of consciousness

Its to be noted that symptoms usually develop within a few minutes to a few hours.

It’s advisable to seek medical attention if facing one or more of the above symptoms. It’s because food allergy aggravates if ignored and can cause fatalities.

What are the tests to detect a Food Allergy?

Sometimes food allergy is confused with intolerance. Hence, the following tests help doctors identify a food allergy and devise means to treat it.

Skin Prick Testing

Doctors take a tiny amount of the suspected food and prick it into the skin using a needle. The skin is then monitored for reactions.

Blood Test

Sometimes the doctors also conduct a food allergy test by drawing blood and checking for IgE antibodies. IgE, also called immunoglobulin E, is an allergy-related antibody found in the blood in response to a particular food.

Oral Food Challenge

This test is in the doctor’s office, wherein increasing quantities of the suspected food are provided to the patient. If there are no reactions, you can include them further in the diet. Otherwise, it is termed an allergen.

Elimination Diet

The suspected food causing the allergy is removed from the diet for weeks and then reintroduced. This helps identify the allergic food and also links the symptoms.

What are the types of blood tests to identify a Food Allergy?

There are a few types of blood tests to determine food allergy. Knowing more about these can help in early diagnosis and treatments.

Enzyme-linked immunosorbent assay (ELISA, EIA)

The Enzyme-linked immunosorbent assay (ELISA, EIA) tests bind the antibodies and allergen to detect the allergen protein molecule in the body.

Radioallergosorbent Test (RAST)

When the blood is in contact with a certain protein, it may produce IgE or immunoglobulin E antibody. This is responsible for all the symptoms we witness during a food allergy. The Radioallergosorbent Test (RAST) detects these antibodies in the blood to determine food allergy.

Is blood test reliable for Food Allergy diagnosis?

The blood tests for food allergies have limitations. Some foods like nuts or chocolates react differently during the Enzyme-linked immunosorbent assay (ELISA, EIA) test. Similarly, it isn’t the best way to determine food allergy by cooked products since the protein destroys and cannot be detected.

The Radioallergosorbent Test (RAST) also cannot be the best to determine food allergy. Some foods, such as oil, milk, egg whites, etc., miss DNA hence, the testing makes it impossible to recognize. Also, Radioallergosorbent Test (RAST) sometimes anchors a false positive result, making it unreliable.

In any case, doctors don’t entirely rely on blood tests. They further conduct prick tests or oral food challenge to determine the food allergens.

Can Food Allergy be cured?

The only possible way to avoid a food allergy is to avoid the allergen. However, there are emergency medications to reduce the effect of allergy until safely taken to the medical practitioner.

However, there is hope to spawn a cure for a food allergy. There are multiple ongoing researches at renowned laboratories to devise a cure that helps a large population.

Prevention is the cure

Here are some basic rules to stick by to avoid a food allergy-

  • Always read the ingredient list on the label before consuming
  • If in doubt, avoid that food
  • Let your loved ones know about the allergy and allergen
  • Inform them beforehand of medications


Stick to prevention when dealing with a food allergy, and you can easily avoid unwanted complications. Still, if you happen to devour an allergen inform the people around and let them handle the situation.

Food allergy is a common problem yet without a cure. All we can do to keep ourselves and our loved ones safe is imbibe maximum information and act when needed.