The three body nature (cold, hot and temperate)

Avicenna divides people according to (nature) into three categories, and according to (temperament) into four categories.


Nature is an old medical term that differs from the common meaning, and it is a genetic condition acquired from one or both parents. Human nature is affected by the environment, water and air condition, geographical and regional factors, the degree of humidity in addition to the etiquette and rules regarding eating, sleeping, being awake, and others.

The nature is divided into cold, hot and mild.

Most people are classified cold, and this means that their bodies tend to be acidic, while the minority tend to be alkaline, and the rare ones are in the moderate zone.

There is a lot of research out there about acidic/alkaline blood, its impact on health, and how the body deals with both cases. It is available for public information. It is necessary to note that the level of pH in the blood is measurable in medical laboratories, but it is also easily subjected to change, and is affected by the simplest factors such as psychological state and food.

Therefore, it is difficult to determine the predominant state of the blood acidity/alkalinity from a single laboratory test; because it will be useful in knowing the body’s nature during the test period only. Knowing about the human nature will be discussed through other signs in the following topics.

The acidity and alkalinity of the blood are in a very small range around the equinox point, as excessive acidity or alkalinity leads to severe complications. Cold bodies are more susceptible to chronic immune system diseases, as the nervous system is cold, means it tends to be acidic, and consists entirely of cold humor (see the previous topic);

so cold foods quickly disrupt this sensitive system, and therefore it is recommended for patients with some immune diseases such as Multiple Sclerosis to eat spicy foods (this does not mean pepper or cooked food, but rather refers to the self-hot nature, as will be explained in the following topics).

It is interesting that when the body is tended to be acidic, the person craves cold foods that increase the acidity in the body instead of neutralizing it.

For example, when a person is sad or anxious, he tends to eat comfort foods such as chocolate, cakes, potatoes, and others, and these foods are self-cold that give a temporary feeling of comfort, but they increase the coldness of the body and have a negative effect. Therefore, Avicenna set a law regarding the messages we hear from our bodies:

If you are in a healthy state (physically and psychologically), then eat whatever you desire, but if you are in poor health (physically and psychologically) then do the opposite.

Before regularizing on Avicenna diet to heal, I used to order a lot of fish, tamarind, and jujube, and with a quick look at what I was eating, it showed my excessive tendencies for cold food. The last attack I suffered was due to excessive intake of jujube, and I will address this in a separate topic.

Although the primary nature is a genetic condition (for example, I am cold-bodied, and so it will always be), but I can avoid the diseases that I am most vulnerable to because of this nature, by eating foods and practicing behaviors that aim to balance the condition rather than exacerbate.

To clarify, I was born with a cold nature, and because I was not aware of this, I ate cold foods, performed practices that increase body coldness, and I experienced extreme cold psychological states that also intensify cold such as tension, depression, and so on for years.

As a result, instead of improving my body status and bringing it closer to moderation, I deepened in the cold nature until I reached the current situation of Multiple Sclerosis. Now because I understand the reason, I can work on fixing it.

Avicenna mentioned in his book after explaining the three natures (and, you understand from this that moderation is closer to heat than cold), is important to note that the character of the body (body nature) depends on the acid and alkaline tendencies of the blood in addition to the levels of humors, so the increasing of both or one of cold humors such as phlegm or black bile contributes to the body coldness, and the increasing of one or both of hot humors, such as blood or yellow bile contributes to bringing the body closer to heat.

The difference between Nature and Temperament

The term (temperament) comes from the word mixing, meaning mixing and merging. Temperament is not heritable, like nature, but rather is symptomatic, and an individual temperament may prevail in a certain period of his life, and another temperament prevails in another period.

Temperament is determined by the levels of the four humors in the body, which are the blood (hemoglobin), and its located in the heart and the veins, the yellow bile or (bilirubin), and it is stored in the gallbladder and phlegm (white blood cells), and the black bile, which is Erythrocyte Sedimentation Rate (ESR) and it is located in the spleen and veins. In case that one of the humors prevails over the others, the body is described by the predominant humour, for example, bile, phlegmatic, bloody, or melancholic.

The topic of temperaments was discussed in the previous topics. It will be discussed in more details in the upcoming topics. The nature of hot and cold foods will be expanded in the upcoming topics as well. However, for a quick reference for the classification of common foods, please review the topic of food mixtures as mentioned in Avicenna’s medicine. For more information in this field, I recommend researching the acidic and alkaline conditions of the body and their effects on organ functions and health in general.

The topic is excerpted from the explanation of the book “The Law of Medicine”