Because IgG blood tests have yet to be demonstrated to detect food sensitivities or allergies, there is a lack of evidence to justify making modifications based on their findings. The limits indicated by IgG test results may cause you to forego beneficial foods unnecessarily. For example, if your IgG test result is high, you might believe that you need to avoid all dairy products. However, studies show that people with milk allergies tend to have lower levels of IgG antibodies against milk proteins than those who do not have allergies.
IgE blood tests are more useful in determining specific allergies. However, because not all allergens make IgE antibodies, these tests cannot reveal potential sensitivity to foods. In addition, not all individuals with elevated levels of total serum IgE have allergies. People with asthma, for example, often have higher levels of total serum IgE than those without asthma.
Food sensitivity tests measure the amount of specific antibodies present in your blood after you have been exposed to a particular food. Because different foods can trigger different types of allergies, it's possible that some foods can raise antibody levels above the limit of detection but others cannot. In addition, certain factors may affect how well a particular test measures antibodies against specific foods. For example, if you are eating a lot of fish than normal, then you should interpret test results regarding that food with caution since there could be other factors affecting the result.
There is little evidence to support the accuracy of IgG testing for food sensitivities. As a result, Everlywell has gotten a lot of flak for giving this sort of testing, particularly from immunologists. However, because food allergies are so common, it's possible that someone without these allergies may show signs of reaction when eating certain foods. In this case, the test would reveal that fact.
The Food and Drug Administration has not approved this kit. In truth, the FDA does not currently regulate many types of at-home testing kits. The American Academy of Allergy, Asthma, and Immunology (AAAAI) does not believe that IgG testing are reliable for identifying food sensitivity, also known as food intolerance.
However, these kits may be useful in helping you identify what foods are causing issues for your body by showing you how your blood reacts to them after they have been eaten. This can help you determine if certain foods are likely causing problems for you personally.
Your body is equipped with natural defenses against harmful substances it comes into contact with daily. One of these defenses is an immune system which functions as a sort of defense force to protect you from bacteria, viruses, parasites, and other foreign objects that could make you sick.
When your body detects something foreign like a food allergen, it produces antibodies to fight it. These antibodies then stick to the surface of any cells they come into contact with, including cells of the immune system. This action creates a kind of "memory" of that substance so that when you eat it again, your body will know how to react.
Over time, these antibodies can build up inside your body and cause problems if you are eating products containing those allergenic ingredients.
Food intolerances, thankfully, are not life-threatening and do not result in anaphylactic responses. Different antibodies to IgE are examined in food allergy testing. The NHS does not provide food intolerance testing. Your doctor may suggest other diagnostic tests if you have concerns about whether a particular food is causing problems for your digestion.
In a food allergy blood test, a blood sample is collected from a vein in your arm. A lab then tests this blood sample for food-specific IgE antibodies in order to discover potential food allergies. When your immune system identifies an allergen in your circulation, it produces IgE antibodies. These antibodies identify the allergen when they bind to it later. Blood samples are usually taken after an allergic reaction has occurred or may be taken before an event triggers a response. The sample is then sent to a laboratory where the IgE antibody level is measured.
The sensitivity of a testing method can be determined by repeating the test on several different occasions and looking at how often positive results are obtained. If negative results are rarely reported, the test may not be very sensitive. If positive results are frequently reported when the patient does not have the disease, the test may be reporting false positives due to other factors such as the presence of IgE antibodies not related to the disease process. A highly sensitive test would detect positive results even when the patient does not have the disease so that appropriate action could be taken.
For example, a doctor might want to know if a new medication causes symptoms similar to those caused by insect stings. To do this, the doctor could give the patient a dose of the medication and watch to see if any reactions occur. If no reactions occur, the patient does not have an allergy to the medication and another can be chosen.
An allergist may do a blood test in addition to skin testing to detect a food allergy. This entails drawing a tiny blood sample and sending it to a laboratory for examination. The blood is tested for IgE antibodies to certain meals. These tests can identify people who may be allergic to certain foods.
People with food allergies should carry an emergency kit at all times. This will help if they have a reaction to their food supply. The kit should include the following items:
• Prescription medications for any existing health conditions
• Over-the-counter medications such as antihistamines or pain relievers
• A copy of their medical history in the event that they need to seek emergency care
• An epinephrine injection kit (available at pharmacies) for people who suffer from food allergies
• Someone to call for assistance if needed
• Something to write with inkless pen so they can write down what happened
• Some form of identification such as a driver's license, credit card, or health insurance card
• Food items to take with them if they have time before going to the hospital