Introduction to Tiredness


I am presenting this article as a healthcare practitioner with over 30+ years experience in successfully dealing with this common condition.

Tiredness (lethargy) is such as common complaint that people and sometimes doctors overlook the problem. Many have come to regard it as just a fact of life. People who work hard and put in long hours will inevitable feel tired at the end of the day. However, what we are focusing on in this article is the overwhelming feeling of tiredness (lethargy) which is more than the normal and is not greatly helped by extra periods of rest and sleep or medical intervention.

Cause of Tiredness (lethargy)

There are many medical conditions which can cause low energy levels and lethargy. Common medical conditions such as anaemia or thyroid imbalance can lead to this state of chronic tiredness. Your GP will do blood tests to quickly confirm or exclude such common causative factors.

However, having done all the relevant blood tests, and having received the “all clear” from the doctor, a significant number of people continue to battle against this problem of chronic low energy. Such people will be very surprised to find that in a significant number of cases, food intolerance could be an important contributing factor.

How Does Food Intolerance Cause Tiredness?

Food intolerance means that certain foods are not digesting properly and such foods will lead to a toxic state within the digestive tract. As a car gets its power from the petrol that we feed it, so also we get power and energy from the fuel that we feed ourselves. In our case, food is that fuel and our source of energy and vitality. If you are not able to digest the foods that you are eating, such foods begin to ferment and putrify within your digestive tract and rather than feed you, such foods start to slowly poison you. It is because food intolerance produces no immediate or obvious symptoms that it has been overlooked by the general public and by the medical profession in general.


When someone thinks about tiredness, lethargy or chronic low energy levels they immediately think of anaemia. This is because the link between anaemia and such symptoms is very strong. There are different types of anaemia but iron deficiency and Vit B12 deficiency is very common. Sometimes by increasing your intake of iron rich foods or by taking Vit B12 supplements, you can improve the situation.

Iron Rich Foods:

  1. Animal Foods (best source): – red meat, fish (especially shellfish), poultry (chicken liver )
  2. Plant Foods: – spinach, lentils, beans

However, we have found that significant numbers of people suffering with iron deficiency anaemia have an intolerance to foods such as beef, lentils, beans etc. The reality is that if you are intolerant to a particular food, you cannot fully digest that food and equally you will not be able to fully absorb all of the iron content of that food.

The same principle applies to osteoporosis. The majority of people suffering with osteoporosis are not in fact eating too little dairy products. The reality is that milk (dairy products) intolerance is very common and such people, in spite of eating adequate amounts of dairy products, are ending up with osteoporosis because that can’t digest and in turn can’t absorb the calcium from the dairy products they are eating.

Additionally, food intolerance results in a mix of undigested foods travelling down the digestive tract and this leads to irritation and inflammation of the delicate mucosal membrane that is lining this tract. The absorption of nutrients into the bloodstream takes place through this delicate mucosal membrane and if it is inflamed and irritated by these toxic, undigested foods, it renders it less able to absorb many of these micronutrients.

Thyroid Antibody Test

Thyroid Imbalance


Thyroid imbalance, and especially hypothyroidism, can cause symptoms of exhaustion as a result of low thyroxine levels. In very many instances, thyroid disease falls into the category of autoimmune disease. This means that the person’s immune system is attacking their own thyroid gland. Food intolerance could be a primary cause.

Poor gut health (excess of undigested foods and damaged mucosal gut wall) marks the beginning of allergies, intolerances and autoimmune disease. (Dr. Natasha Campbell McBride)

The Solution


By finding your intolerant foods and eliminating them from your diet, you stop the creation of these gut toxins. The digestive system begins to work more efficiently and is again able to absorb nutrients into the bloodstream. Free from this toxic load, the body quickly recovers its former energy levels. As a result, the immune system settles down and stops the attack upon the thyroid gland.

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