Allergies and Intolerances to Food  

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Finding a good herbalist

Most of what's written in this article is entirely suitable for a person to work through themselves but, especially if things are quite bad, or you just know that you need further help, then there may be much benefit in finding a good herbalist to guide you on to a safe and strong treatment program. There's a short write-up to suggest how you might go about finding such a person here

Allergy vs. Intolerance

Both allergies and intolerances clearly affect many people and it has often been seen that the turning point in a person's health is when they remove those foods from their diet that were doing them harm.

Firstly, it is important to understand the difference between an allergy and intolerance because, whilst allergy gets almost all the attention in conventional medicine, many chronic health problems are more deeply connected to intolerances.



An ‘allergy’ is what happens when contact with a substance causes large amounts of histamine and other inflammatory chemicals to be quickly, sometimes violently, released.

Allergies manifest so quickly because the immune system thinks there is a toxic invasion taking place and tries to get rid of the substance as quickly as possible. Swelling, coughing, scratching etc. are all attempts to try to push the substance away as quickly as possible.

In extreme allergies, a person can have what is called an ‘anaphylactic reaction’ where their mouth and throat swell to the point that they have trouble breathing. In such emergencies, an adrenaline injection may be needed to prevent catastrophic consequences. Antihistamine drugs are usually recommended for less severe allergies.


'Intolerances' equally involve the immune system, and in many ways are just as much an 'allergic' reaction, but the crucial differences are the cells that are involved and the time factor.

Allergies primarily involve white blood cells called IgE cells, whereas intolerances are primarily mediated through IgG cells.

The activation of IgG cells causes a slower inflammatory process to take place. They are mostly caused by reactions to food and can take many hours to start to show symptoms compared to as little as minutes, or even seconds, for a classical allergy.

Intolerances are also much harder to diagnose than allergies. You may be highly intolerant to milk, or gluten, to use two most common examples, but skin prick tests and conventional IgE blood tests may tell you that you have no allergy to these substances whatsoever.

Intolerances are often a root cause behind both eczema and asthma. They are also often involved in other health problems that involve the immune system or where there is chronic inflammation in the body.


How are allergies & intolerances diagnosed?

The skin-prick method

Many people with health problems that look like they might be caused by 'allergies' will receive a skin prick test. This is very helpful for identifying the immediate, classical IgE allergy type reactions as described above because the skin immediately swells when exposed to a tiny amount of the suspected 'allergen'. The degree of swelling then gives a rough indication as to how strong the allergy is.

Unfortunately, and perhaps because these skin-prick tests usually include some foods along with pollens, dust-mites etc. many people think that if they or their children have had one of these tests then they are all clear and it must be something else that is the problem.

The skin-prick method does not help with diagnosing food intolerances, not at all. They can only tell you what you are allergic to, not what you may be intolerant to.

The elimination and challenge diet

The 'gold-standard' method of diagnosing food intolerance is the elimination and challenge diet. This is whereby you completely exclude the suspected food or foods for approximately two weeks and then re-introduce the food or foods that have been avoided, noting changes in your symptoms both off and on the foods.

Dairy products and Gluten-containing foods are the most common sources of food intolerance and, for many people, it will be appropriate and beneficial to trial an elimination and challenge diet with one or both to see what happens. Practical instructions on the 'how-to' of this are shown in the links below


Testing for allergies & intolerances

There are a number of alternative methods in the health market said to be able to diagnose food allergies and intolerances. They all look authentic and are no doubt well-marketed, but the truth is that most of them are bad; based on shonky science or no science at all.

You need to be very careful in this area because; aside from losing your time and money, there can be lasting harm from being wrongly advised by an inaccurate method.

Some common examples of these methods include the ‘blood-group diet’, 'saliva-testing', 'hair-testing', 'vega testing' or any kind of system where someone puts a sensor on your skin and measures variance in electric currents.

If you do such a test, or follow a diet plan based on something like your blood group, they all inevitably tell you that you are allergic to a number of different foods, almost always including dairy or gluten or both.

Because many people genuinely do have an intolerance to dairy or gluten, they will get significant improvements from avoiding them however, in the meanwhile, there are a handful of other harmless foods that have also been 'tested' as being bad that they also believe they now have to avoid.

Not only can this set the stage for an overly restricted diet, but it can cause much long-term stress as it leads to a person struggling to navigate through life with a list of prohibited foods that are in fact perfectly okay for them to eat.

In this area, it is crucial to find the truth and not be deceived by pseudo-scientific tests. You simply cannot accurately or scientifically diagnose food allergy or intolerance using electronic gadgets, hair or saliva samples. Hair or saliva tests, for example, give reports that look like the tests have been done with authentic scientific methods and sophisticated laboratory machines.

This is what they want you to think, in reality they're done by a person in a cubicle with a sample of the hair or saliva who is then using something similar to a pendulum to wave over it and make marks on a laptop that then prints the fancy report. Maybe there are such gifted psychics in the world, maybe not. You would never get a chance to meet the person in the cubicle to make up your own mind about them. My objection is that this whole process obviously convinces the public that there is a real science basis to them and this is just a deception, plain and simple.

Aside from the elimination and challenge diet as described above, one testing process for food intolerances that does have credibility are blood tests that pick-up IgG intolerances.

Unfortunately, most routine blood testing does not include this, though you can ask your doctor if they are able to order IgG tests for you as an increasing number of laboratories do offer this service.

For quite a few years now, our clinic has been using the IgG blood test from Cambridge Nutritional Services in England. These tests are quite expensive, but they have proven to be highly useful in practice.

Just to be clear, we have zero financial connection to the suppliers of these tests, but in many parts of the world you can order a test from them directly that you can do at home by looking up Cambridge Nutritional Services online (

People are understandably daunted at the idea of doing a blood test by themselves, but their website gives a video demonstration of how to do the test and likewise the pamphlet that comes with the test is well explained and makes it easy to do. The results are available within an hour.

I want to mention that the pamphlet that comes with the test rather downplays the importance of positive reactions that only show a 'mild reaction'. It would be better if they said that it depends on the severity of the related health condition as to how strictly the person should avoid any foods that get flagged. We have found that for reactions at the mid-blue to strong blue level a strict avoidance of the related foods is essential to see a resolution to the health problems that are being caused by food intolerance and that most people need to maintain the discipline of total avoidance for 3 months for there to be the chance of a lasting cure


Can food intolerance be cured?

The answer to the question 'can food intolerances be cured?' is... maybe!

The gold standard for how long you have to completely avoid a food that you are intolerant to is 3 months. Don't plan for a short-cut, this is the amount of time it takes for many of the white blood cells that are involved with intolerances to live through their life cycle.

How you then go about seeing if you have cured the problem also needs care. This process is called 'three strikes and you're in' and is described next.

We hope and expect that many children who have intolerances will be able to grow out of them if they take a long enough break from what they are reacting to and they get healthy.

However, the older or sicker someone is the less chance there is that this will happen without both a total avoidance of the food intolerances as well as taking measures to improve overall health. In particular it can be essential to nourish and support the immune system with herbs and other nutrients, more on this subject here

Withania somnifera


Three strikes and you're in

If you have accurately diagnosed a food intolerance, then you must avoid that food completely for at least 3 months. Don't cheat, don't think a tiny amount won't hurt. Just stop it altogether for no less than 3 months.

Then, the first time you re-introduce the food you have been avoiding, eat only a tiny fraction of a portion. For example, a single bite of a piece of bread, or just a sip of milk, or just a half teaspoon of egg etc. Then wait for 48 hours. Do not eat any more of the food until 2 whole days have passed.

It may well be that you will feel nothing bad happening at all, which is obviously a good sign. However, do not worry if you get some mild reactive symptoms such as a very slight stomach upset, or a slightly itchy skin, or a feeling of being a little edgy or out-of-sorts etc. This is not unusual and, so long as those symptoms are mild and soon pass within the 48 hours, then the 'immune army' of your body has said 'ok, we know what that was, but we aren't going to get up in arms about it'. In other words, you are starting to develop some tolerance.

If you get any symptoms that are either quite disturbing or that don't completely pass within the 2 days, then you need to accept that you are not ready to tolerate this food and must go back to completely avoiding it again. This will no doubt be a disappointment but don't let it stop you trying again later, things may still change with time.

However, if you do feel better then you should go to the second step. This is to eat a substantially larger portion of the same food but still not quite a full serve e.g. half a slice of bread, 50mls of milk, a quarter of an egg etc.

Again, wait for 2 whole days to allow your immune system to see that this substance does not pose any serious threat and again don't over-worry if you feel like you are getting a mild reaction to it so long as it soon passes and it gives you very little real physical disturbance. This means that the body is in the process of learning that this food is not a serious threat and can be safely consumed more than once and in a larger quantity.

The third step, and again make sure this is after a full 48 hours, is to eat a still larger portion of the food, perhaps twice the amount as before, and again wait for two days to see if anything happens and, if it does, to see if it quickly settles down again. If you have carefully taken the first two steps without any real trouble there is a good chance that this 3rd stage will go well too, because you have been retraining your immune system to redevelop tolerance. .

After this process, you should carefully and systematically keep eating the previously avoided food, reminding your immunity that this is a friend rather than a foe and so keep establishing the food as 'safe'. Do not overeat it, or you may become intolerant again, but do not avoid it either and, if all goes well, you will have re-established tolerance.

Calendula officinalis

Please understand that I cannot personally advise you without seeing you in my clinic.
This living 'book' is my labour of love so, wherever you are, I wish you peace & good health!



© 2011 R.J.Whelan Ltd