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Food Allergies v. Sensitivities v. Intolerances - The Three Most Common Food Reactions That You Are Experiencing

Dr. Alison Chen
6 December 2018

The Three Most Common Food Reactions That You Are Experiencing
by Alison Chen, ND

Introduction Food Sensitivity

Do you ever feel bloated or constipated? Maybe you experience headaches or skin reactions that appear to have no known cause? Maybe you’re constantly tired, unable to concentrate or focus? The reason for these reactions may surprise you and have you looking no further than your dinner plate.

Digestion is an essential part of our physiology. It includes enzymes that break down that bagel you ate for lunch into smaller, useable molecules. It also involves the mucosal lining of our intestine, which allows for absorption of these molecules into our bloodstream. And don’t forget our immune system, which enables us to assimilate these food molecules into our bodies without mounting a foreign invader attack on them. With multiple players and parts, our digestive system is important to our everyday living, and when working correctly, helps us utilize the food we eat to survive and thrive.

Food Sensitivity

But when our digestive system is not functioning properly, this can result in symptoms such as bloating, cramping, constipation, and diarrhea, among others. Treating these symptoms can provide relief; however, it’s always best to find the root cause of your digestive problems, and sometimes the source may be related to something you put into your body every day: food.

Deleterious reactions to many of the foods we eat are prevalent, whether they are hidden or life-threatening. Approximately 6% of children and 3–4% of adults have food allergies, while those with food sensitivities and intolerances are more difficult to estimate.[1] Some suggest that between 45% and 60% of people may be affected by IgG-delayed hypersensitivities, but I might guess that everyone has at least one food that causes a heightened immune response at any given time.[2]

While many of us may react negatively to certain foods, there is still confusion about what constitutes a food allergy, sensitivity, or intolerance and the differences between these reactions. Whether it’s a milk allergy or a sensitivity to gluten, it’s always beneficial to see how your body reacts to the things you eat every day to foster greater health and wellness.

So, what is the difference between these reactions and what can you do if you feel that something in your diet is doing more harm than good?

What is a Food Allergy? Food Sensitivity

Immune Reaction: IgE—Type I Hypersensitivity / Anaphylactic

Physiology: Typically, a clear cause and effect with a rapid onset, whereby mast cells and basophiles (immune cells) release histamine when exposed to a reactive food molecule (antigen) and cause an inflammatory response (red, swollen, itchy) that varies from uncomfortable to life-threatening.

Timeline: Symptoms occur immediately after eating an offending food, with residual effects usually clearing within 5–7 days but may last up to 2 weeks.

Signs and Symptoms: These can include inflammation of the skin (rash, hives, eczema, itchiness), respiratory system (asthma, wheezing, restricted airflow), digestion (cramps, nausea, diarrhea) and vasculature (swelling). These reactions can be serious and even life-threatening, as seen with anaphylaxis.

Example:Seasonal allergies like hay fever and the common peanut allergy.

What are Food Sensitivities?

Have you ever eaten a meal and, within minutes or even hours after, you feel as though your body is bloated and being dragged down by bricks? Maybe you felt unable to stay awake and, let alone, think clearly? This delayed and often chronic reaction may be due to an IgG antibody immune reaction.

Immune Reaction: IgG—Type III Hypersensitivity

Physiology: Includes a delayed onset, with release of inflammatory cytokines (immune cells) and a cascade of local and systemic events. IgG reactions are often dose-dependent on the amount of antigenic food ingested and are typically milder, slower, cumulative, and nontypical.

Timeline: Food sensitivities are often difficult to diagnose, as IgG antibodies are produced approximately 30 days after food antigen recognition. Once a threshold of IgG antibodies are made, symptoms begin 24–48 hours postingestion, and IgG antibody levels rise slowly and linger for up to 3 months.

Signs and Symptoms:Symptoms can vary and include migraines, cognitive “brain fog,” behavioural difficulties in children with ADHD, chronic digestive concerns (constipation, diarrhea, excessive gas, IBS, IBD), skin issues (acne, eczema, atopic dermatitis), low energy, weight gain, water retention, and joint pain.[3]

Example: Gluten sensitivity (not to be confused with celiac disease, which involves an IgA immune reaction).

What is a Food Intolerance? Food Sensitivity

Immune Reaction: Non–immune-related.

Physiology: Involves an inability to break down food into basic units for absorption by the body due to the absence of necessary enzymes.

Timeline: Reactions usually occur within 30 minutes of ingesting an aggravating food, and effects can last a few hours.

Signs and Symptoms: Explosive diarrhea, excessive gas, low energy, fatigue, dehydration, and malnutrition.

Example: Lactose intolerance, but could also be casein or ovalbumin sensitivity.[4] If taking lactose-free products or lactase enzymes while consuming dairy products still creates uncomfortable symptoms, it may be another protein you’re intolerant to, or more likely a food sensitivity.

How Do You Determine if You Are Reacting to the Foods You Eat? Food Sensitivity

The purpose of the hypoallergenic diet is to remove the most common (top 5) offenders in your diet—including wheat, dairy, corn, soy, and eggs—and monitor how you feel. A thorough elimination takes 6–8 weeks to fully complete and involves lots of meal-planning. While it isn’t always simple or easy to do, it can be very enlightening. It is also important to note that although it is considered a diet, it is not a diet to lose weight, but should rather be viewed more as a food sensitivity test.

To complete the elimination challenge, follow these steps:

  • Eliminate possible food aggravators for three days.

  • On the fourth day, choose one potential food aggravator and eat three servings of it.

  • If you have no change in symptoms, wait another couple of days, while keeping your diet consistent before moving on to the next food aggravator.

  • If you do have an aggravation, avoid eating that food until you have tested all your food sensitivities and only eat it in limited amounts.

Also remember: Many nongluten or nondairy foods may not be as healthy as you think and may have poorer-quality ingredients as substitutions. Try and stay away from packaged, canned, processed, and deep-fried foods, and be cautious of dehydrated and dried foods for they often contain added sugars and preservatives. Raw and fresh is often your best bet for optimal health.