It is imperative to know about Food Intolerance (FI) when discussing dietary challenges to your health, specifically allergies. Though it is a much less known and understood dietary challenge, none the less, it is absolutely critical you come to a basic understanding of the potential destroyer of health!


DAIRY: Lactose and Casein

GLUTEN: Including Celiac Disease

FRUCTOSE: Not to be confused with Fructose Malabsorption

YEAST: Candida

(Others include a range of food additives which are used in the food processing and preservation of foods and beyond the scope of this article)

If you are fortunate and do not suffer from any of the above food intolerance you are in the MINORITY. It is believed that 75% of the population has some intolerance issues with any one or any combination of the type of foods listed above.


DAIRY (LACTOSE): 3 in 4 or 75%

GLUTEN: 1 in 7 or 15% (this is a conservative estimate)

FRUCTOSE: 1 in 3 or 35%

YEAST: 1 in 3 or 33%

Interestingly, it is estimated that sufferers of the more common topic of “food allergies” are 3% in children and only 1% in adults.

FI is much more common than food allergies. The range of symptoms which can be induced by food intolerance is very similar to those caused by a food allergy, so that on initial presentation, it can be difficult to differentiate between the two conditions. However, food intolerance may also lead to more diffuse symptoms such as drowsiness, fatigue, irritability, headache and muscular aches and pains.

So, what causes FI? There is no simple answer to this. Many reasons have been put forward including the lack of a particular enzyme, that it is inherited, induced by stress or illness, the result of an impaired immune system, environmental pollution, lack of adequate nutrition, etc.

A distinct advantage of determining if you have allergy issues is its SUDDEN and SEVERE response. Unfortunately the response to food intolerance can be up to 48 hours after the food was consumed, making it very difficult to determine the food’s causative component. The severity of symptoms in food intolerance is dose-dependent, and the dose can be cumulative over days of ingestion. This characteristic further increases the difficulty of diagnosis, as the symptom-inducing chemicals may be common to many foods, so that different foods may appear to cause symptoms on some occasions, but not on others.

Another difference between food allergies and intolerance are the causative factors. Allergies are a “nurture” issue and intolerance are a “nature” issue. Personally speaking, my “nature” is Irish/Scottish and I have the highest tendency of all of the genetic ancestries’ to have gluten intolerance (Irish, English, Scottish, Scandinavian, and other Northern European and Eastern European heritages). This specific intolerance has actually become progressively worse as I have aged.

Gluten is a highly complex protein that occurs in four main grains: Wheat, rye, and barley (there is some controversy over oats, but I believe oats are fine/the issue is cross-contamination). Gluten is present in all types of wheat grain like whole grain wheat, wheat bran, spelt, triticale and others.
This means Gluten is also present in all baked foods that are made from these grains: bread, pies, cake, breakfast cereals, porridge, cookies, pizza and pasta. There are thousands of processed foods which contain Gluten. Just in case you were wondering, BEER is doubly problematic as it not only contains a very high amount of gluten but also has a very high Glycemic-Index.

If you have concerns about your health and you believe that your issues may stem from a FI you may want to work with a professional and/or implement an elimination diet, as food intolerance is very difficult to clinically test for.