The 21 Day Elimination Diet To Identify Food Sensitivities & Banish Mystery Illnesses

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The 21 Day Elimination Diet To Identify Food Sensitivities & Banish Mystery Illnesses

Food sensitivities don’t just cause an array of unpleasant reactions which affect day-to-day life, they can have long-term implications for overall health.

So many people have food intolerances which are causing stress to their bodies, yet they don’t even know it! These intolerances lead to issues like bloating and digestive discomfort, IBS, migraines or headaches, fatigue, skin conditions like eczema, aches and pains, sinus or respiratory issues, and a general feeling of suboptimal health.

If you suffer from any of these issues or others for which doctors haven’t pinpointed a specific cause, it may be worth your while checking for food sensitivities. Anyone with an autoimmune condition, or with a known food allergy who is still experiencing symptoms, should also take a closer look at their diet.

Luckily, you don’t have to spend a small fortune uncovering these sensitivities! With a little detective work and some time, you’ll get to know what disagrees with your body thanks to a fantastic diagnostic tool known as the elimination diet.

An Elimination Diet – The Gold Standard

Generally considered as the ‘gold standard’ when it comes to unmasking hidden food intolerances, the premise of the elimination diet is simple: eliminate certain foods for a period of time (usually 21 to 28 days), then slowly reintroduce them intermittently and take note of any adverse reactions or symptoms you experience.

The goal is to pinpoint exactly which foods are causing your health-related issues, so you can reduce or completely eliminate them from your diet.

Although allergy tests – in the form of blood samples or patch tests for example – are quicker and easier than undertaking an elimination diet, they can be expensive and the results are often inconsistent and unreliable.

Elimination diets also provide more motivation to quit problematic foods such as bread or ice-cream, as the positive effects of forgoing these items are quickly experienced. The same cannot be said for reading blood test results from a print-out!

A Two-Step Process

In its most basic format, an elimination diet consists of two steps: the elimination phase, and the reintroduction phase, which are outlined in more detail below, but first you need to prepare.


Of course, it’s difficult to wake up and begin this diet without a little forward planning, so the preparation stage should also be considered. Keep in mind the old adage ‘fail to prepare, prepare to fail’!

To get ready for your elimination diet:

  • Familiarize yourself with the list of foods you should be avoiding, and take note of ‘safe’ foods you can eat during the experiment. Printing off suitable recipes is also useful.
  • Clear out all non-compliant items from your kitchen or, if you live with others, move all these items to one ‘forbidden’ cupboard.
  • Stock up with compliant foods, and ensure you have a few ready-to-eat items on hand for when hunger or cravings strike. A variety of fruits, pre-chopped vegetables with dips, and homemade protein bars can save you from falling off the wagon and jeopardizing the results of your diet.
  • Get used to reading food labels, and familiarize yourself with the many aliases under which allergens hide. For example, names like hydrolyzed vegetable protein, maltodextrin, and natural flavors can all indicate that a product contains gluten (although this should be clearly marked somewhere on the label); and whey, curds, whey protein concentrate, and caseinates are all other names for lactose. Avoiding processed foods and making your own items from scratch is the best way to reduce the risk of accidentally ingesting a suspect food.

Once you have covered all these steps, and have prepared yourself mentally for undertaking an elimination diet, you’re now ready to move onto the first phase of the plan: elimination.

The Elimination Phase

At this point, it’s time to remove the most common offenders in terms of food allergies. Because many people have multiple allergies, it’s important to remove all items together, rather than eliminating them one by one.

The most common foods removed from the diet include:

  • Dairy
  • Eggs
  • Gluten
  • Corn
  • Soy
  • White potatoes
  • Tomatoes
  • Citrus fruits
  • Peanuts
  • Alcohol
  • Caffeine
  • Vegetables oils (except olive oil, flaxseed oil, and coconut oil)
  • Processed foods and meats, as many additives trigger intolerance symptoms

You should also remove any foods which you eat every single day, like bananas or chicken, as you may find you have become intolerant to them simply because you consume them so frequently.

Although the list seems exhaustive, it’s far from it. You can meet all your nutritional needs by eating a diet rich in:

  • Grains and pseudo-grains like rice, quinoa, millet, amaranth and buckwheat
  • All fruits and vegetables including sweet potatoes (but excluding those listed above)
  • Nuts and seeds (except peanuts)
  • Beans and lentils
  • Organic and grass-fed meats
  • Fresh fish
  • Herbal teas, and homemade juices and smoothies
  • Cold-pressed healthy oils
  • Dairy free milks such as unsweetened rice milk, coconut milk and nut milks

The Reintroduction Phase

While this phase can seem confusing, it is often needlessly over-complicated, and is actually relatively straightforward.

Once your 21 to 28 days on the diet are up (depending on how long it takes symptoms to subside), simply pick one of the items you eliminated and reintroduce it.

Eat a good-sized portion of it for one meal, and note any reactions over the next 48 hours. If you experience no symptoms, try it again and take note of how you feel. Once again, if you don’t have any adverse reactions, it’s likely that this food is not the cause of your complaints, and can be rotated back into your diet.

Now, move on to another food and reintroduce that in exactly the same manner.

What Symptoms to Look For During the Diet

The elimination diet only works if you make an effort to really pay attention to the messages your body is sending you. Throughout both stages of the diet, you should take note of how you feel. Don’t just look for signs that your ailments – like migraines or PMS – have improved. Be aware of all other changes too – in terms of energy levels, sleep quality, memory, mood, skin condition, digestive health, general wellbeing etc.

During the elimination phase, you may initially feel worse and suffer increased tiredness, skin eruptions, or headaches. This ‘healing crisis’ tends to indicate the diet is working, and your body is removing toxins caused by foods that don’t agree with you. Once the body has ridded itself of these toxins, you will begin to feel much better. (Of course, if the symptoms are extreme, or persist for more than 10 to 14 days, consult your doctor.)

Throughout the reintroduction phase, you should be especially vigilant as to changes in your health and general state of wellbeing as these could indicate your problem foods. Even seemingly positive changes at this point, such as increased energy, should be noted. These can actually have underlying negative implications, as they may be your body’s response to the stress a particular food is causing it.

There are a couple of tools which can help you pinpoint your trigger foods too. These are:

A Food Diary

Throughout the experiment, record details of your food intake, energy, mood, and psychical symptoms and look for patterns in relation to the timing of your response and your food intake. Get yourself a food journal to keep track.

Pulse Test

Because food sensitivities create a stress response in the body, testing your resting pulse rate after eating a potential problem food can give you a greater understanding of your body’s reaction to it.

Immunologist Dr. Arthur Coca devised this test in 1956, and it is still used by many natural health practitioners today.

Simply record your pulse each day before rising, before bedtime, before each meal, and at 30 minute intervals after each meal for the first 90 minutes. A rise of 10 or more beats in the resting pulse rate is a sign of food sensitivity, especially if you note other symptoms too.

While the pulse test is by no means an exact science, and is considered unreliable by some, it can be helpful when used in conjunction with a properly executed elimination diet and food journaling.

Removing Foods to Which You Are Sensitive

When you do experience symptoms of intolerance to a particular food after reintroduction, you should remove it from your diet. In his book The Allergy Handbook, allergy expert Keith Mumby explains that most people can incorporate such foods back into the diet after they have avoided them for a certain period of time.

He suggests avoiding the food for at least six months before attempting to reintroduce it. If you still experience symptoms, eliminate it for another 12-month period. If, after this time, it still causes you issues, it’s unlikely you will ever be able to tolerate that food again.