Illness and Disease


Today I wish to discuss a pair of words: Illness and disease. I think that they are interesting because very often they are considered to be synonymous, and especially by Spanish-speaking doctors, who only have one translation for both these words: Enfermedad.

The Merriam Webster dictionary states that illness is ” a condition of being unhealthy in your mind and condition”, and that it is ” a specific condition that presents your body or mind from working normally”.  The same dictionary states that disease is “an illness that affects a person, animal or plant.” And, that is “a condition of the living animal or plant body or one of its parts that impairs normal functioning and is typically manifested by distinguishing signs and symptoms.”

In Wikipedia, it says that “Illness and sickness are generally used as synonyms for disease.” But then it continues by saying that “However, this term is occasionally used to refer specifically to the patient’s personal experience of his or her disease.” This leads me directly to the reason for writing this short piece on Easter Saturday!

At present, I have just started reading Suzanne O’Sullivan’s ” It’s all in your head.”


This book has been nominated for the Wellcome Book Prize of 2016, which celebrates the best new books engaging with any aspect of medicine, health or illness, and in the first chapter the author speaks about the difference between disease and illness, which led me back to the often repeated question that I regularly hear and have to try and answer. I quote Dr O’Sullivan because I think it is an excellent, and clear response.

“Illness is not the same as disease. Illness is the human response to disease. It refers to the person’s subjective experience of how they feel but does not assume any underlying pathology. Illness can be either organic or pathological. A person can have a disease but not be ill. For example, a girl with epilepsy has disease, but if she is not having seizures and the epilepsy is asymptomatic she is not ill. …….. Everybody’s experience of illness is their own, and that is where illness becomes distinct from disease.”

She then continues, ” if you take one hundred healthy people and subject them to exact the same injury you will get a hundred different responses. That is why medicine is an art. “


So, because of this beautiful explanation of the difference between “illness” and “disease” by Dr Suzanne O’Sullivan I am raring to continue reading her book…..

Happy Easter to you all.

Leave a Reply

Your email address will not be published. Required fields are marked *