by Deborah Lynn Blumberg April 08, 2021 3 min read

If you have experienced a reaction to a particular food or environmental trigger, you may wonder how this happens and why it can range from an immediate (even life threatening) response to a delayed, more mild (yet still unpleasant) range of symptoms. This is where understanding the difference between an allergy and a sensitivity is helpful, as well as how the immune system works to defend the body against any potentially harmful invaders it is exposed to.

IgG and IgE are two of the main types of immunoglobulins or antibodies in our blood. They form a group of proteins our immune system makes to fight off foreign invaders including:

  • Viruses
  • Bacteria
  • Fungus
  • Animal dander
  • And more

When our body is functioning optimally, these antibodies work to protect us from illness, but they can also trigger a reaction if you are allergic or even sensitive to certain invaders.

Severe Allergic Reactions (IgE)

An allergy triggered by Immunoglobulin E, which was discovered around 50 years ago, is the most commonly known and immediate allergic response.

When someone with a peanut allergy eats a handful of nuts, their body mistakenly sees the nuts as a dangerous, foreign invader and instantly produces IgE antibodies, which are found in the lungs, skin and mucous membranes. These antibodies flood to cells that release chemicals and cause a severe allergic reaction.

Within just a few minutes of being exposed, the person with an allergy may experience trouble breathing, swelling, itching, congestion, repeated vomiting, abdominal pain or a severe skin rash. Once the immune system has made IgE antibodies against a specific allergen, each time the person is exposed, their body will overreact. In severe cases, an allergen can cause anaphylaxis -- an immediate, serious and often life-threatening reaction ("shock") to the body.

Subtle, Delayed Response (IgG)

Immunoglobulin G, or IgG are antibodies that protect us against infections by remembering which germs we have been exposed to and mobilizing to fight them off the next time. IgG is the main antibody in human blood, which multiplies and travels throughout the body to defend itself.

Our body can also have an IgG reaction to certain foods we eat. Our immune system can be triggered even if these foods are part of a perfectly healthy diet. An IgG food sensitivity is one that has less serious, but more symptoms and can take anywhere from a few hours but up to 3 days to react. Repeatedly consuming foods you are sensitive to can lead to increasing levels of inflammation and a wide range of more mild but unpleasant symptoms. This can include digestive upset, difficulty losing weight or keeping it off, headaches, learning or mood disturbances, skin issues, muscle/joint pain and overtime can lead to more serious health conditions.

Understanding Your Body and Possible Imbalances

Unlike allergies which are present from birth, food sensitivities can develop over time and most often be linked to improper gut function. Many people have multiple IgG food sensitivities and a simple finger prick blood test can identify the more hidden, delayed-response trigger foods that can start to react in a few hours but take anywhere up to 3 days.

Ongoing exposure to any harmful pathogen, whether it is from food, medication, stress or environmental factors, all affect the integrity of the gut lining and over time may allow these harmful pathogens to enter into the blood stream and trigger an immune response. If foods are the issue, taking an at-home test and following an elimination protocol to rebalance the gut will support your immune system and has shown to be effective in reducing even removing unpleasant reaction.

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