NUTRITION: Food Intolerance Part 1 | Great Health Guide
NUTRITION: Food Intolerance Part 1

NUTRITION: Food Intolerance Part 1

‘Food Intolerance Part 1’ by Dr Helen Dodd published in Great Health Guide (Oct 2016). What is food intolerance? It’s not the same as food allergy and is more common than food allergy. How can we distinguish the difference between food intolerance and food allergy? Read the rest of this two part series by Dr Dodd to discover the factors that can cause food intolerance as well as how to test for it.
Read other Nutrition articles on Great Health Guide, a hub of expert-inspired resources empowering busy women to embody health beyond image … purpose beyond measure.

NUTRITION: Food Intolerance Part 1

written by Dr Helen Dodd

Food Allergy was discussed in the previous issues of Great Health GuideTM, as an abnormal immune system response. However, many people suffer from Food Intolerance after eating certain foods. These symptoms can be similar but are more moderate than in Food Allergy. With Food Intolerance, the immune system does not produce antibodies and thus cannot be diagnosed by a Skin Prick Test. 

What is Food Intolerance? Food Intolerance is called non-allergic food hypersensitivity. The body has difficulty in digesting or breaking down certain foods. This affects the body’s the ability to absorb them through the walls of the gastrointestinal (GI) tract. 

What are the symptoms of Food Intolerance? Food Intolerance is more common than Food Allergy. Food Intolerance symptoms take longer to appear and can occur from four hours up to two days after ingestion. Symptoms can be quite varied and are usually related to the GI tract with diarrhoea, stomach bloating, flatulence, bowel cramps, indigestion, nausea and vomiting. Other symptoms of fatigue, skin rash, asthma, headache and joint pains also occur. 

Can Food intolerance be distinguished from a Food Allergy:

As previously discussed, a Food Allergy is an immune response, which can be tested for and diagnosed with the Skin Prick Test. Food Intolerance is a non-immune response and if an intolerance is suspected then an exclusion diet, or an elimination diet is required for diagnosis. 

Since many of the symptoms of these conditions overlap, it is often hard to distinguish between the two conditions. However, more of the problem food needs to be consumed with Food Intolerance, before the symptoms develop and thus it is harder to relate symptoms to a particular food. 

Want your own FREE COPY of Great Health Guide

& delivered to your inbox each month?

Look to your right…


Another difference is that symptoms of Food Intolerance do not become increasingly severe as with a Food Allergy. However, if the problem food is continually eaten and intolerance is unrecognised, then chronic conditions such as Irritable Bowel Syndrome (IBS) can occur. IBS will be discussed in following issue of Great Health GuideTM

Factors that can cause Food Intolerance. This is not an exhaustive list of food intolerance triggers. Individuals may be intolerant to only one of these triggers or more than one.

1. Lack of an enzyme. Lactose intolerance is a common condition where the enzyme lactase is lacking. Lactose or ‘milk sugar’ is a disaccharide. Lactose is too large to be absorbed and has to be broken down by the enzyme into the monosaccharides, glucose & galactose. These are readily absorbed by the intestine. The enzyme lactase can be absent in the GI tract if:

  • a person has had gastroenteritis or parasites

  • or are genetically unable to produce lactase

When unabsorbed lactose passes into the large intestine, bacteria cause fermentation producing gas, such as carbon dioxide, methane and hydrogen. This builds up in the large bowel causing pain, cramps, bloating and finally diarrhoea.

Testing for lactose intolerance: 

Hydrogen Breath Test. Hydrogen gas from bacterial fermentation in the gut is absorbed into the blood stream and excreted into the lungs. It can be measured in exhaled breath. 

The elimination diet is another diagnostic method where all milk products are excluded from the diet and symptoms should decrease.

Another quick test is to use lactose-free milk and record symptoms. After 2 months when symptoms are no longer present, retest with regular milk to determine if the symptoms reappear. 

2. Salicylates. Plants produce salicylates as defence against insects, bacterial and fungal diseases. They regulate growth, flowering, ripening and ageing of fruit. High levels of salicylates are found in oranges, lemons, berries, tomatoes, eggplant, capsicum and chili pepper. Very low levels are found in pears, apples, pawpaw cabbage, lettuce and potatoes. Any concentrated juices, sauces and jams will contain much higher levels than fresh plants. Symptoms include asthma, skin rashes and stomach pains.

3. Amines. These include amino acids and biogenic amines, which occur when bacteria break down amino acids in food.  Fermented products such as alcohol, soy, pickles, sauerkraut are high in amines, with tyramine in old, matured cheese and histamine in red and port wine.  Symptoms can include flushing of face, headache, skin rash, vomiting, diarrhoea and changes to blood pressure as amines dilate blood vessels.

4. Nitrates & nitrites. Nitrates in green leafy vegetables are the main source in food. However, ammonium nitrate used as agricultural fertilizers can raise the concentration of nitrate in drinking water. Nitrites and nitrates are used as preservatives in processed meats (bacon, ham, hot dogs, salami, corned beef & sausage) and have caused behavioural problems in children. Symptoms include headache, skin rashes and asthma.

5. Sulphites. These are added to wine and foods for preservation, flavour, colouring and to prevent fruits and vegetables turning brown and rotting. Sulphites release sulphur dioxide which is absorbed by the food. Symptoms of intolerance are asthma, hay-fever, hives, skin rashes and breathing problems. 

6. Mono sodium glutamate. MSG is a flavouring present in canned vegetables and processed meats. However, some foods such as soy sauce, parmesan cheese and Roquefort cheese are very high in MSG. Symptoms can include flushing, sweating, chest pain, heart palpitations and headache. These are usually transient and are very hard to diagnose.

In the following issue of Great Health GuideTM, the elimination diet will be discussed including Irritable Bowel Syndrome. 

Author of this article:
Helen Dodd BSc. BPharm. PhD, is a retired pharmacist, continuing to provide information and education on nutrition and diseases that affect modern society. Contact Helen by email. 

The Food Intolerance Management Plan

by Dr Sue Shepherd, Dr Peter Gibson
Paperback.   Published 2011.
RRP $26.95        

1880-216744 copy



Booktopia may vary prices from those published. Postage $6.95 per order AUST/NZ.

To get your FREE MAG each month CLICK HERE.

Love this? Your friends probably will too. 

Why not share the love & forward this article. 

Author Great Health Guide

More posts by Great Health Guide

Leave a Reply