We use the word Nausea to mean when we feel sick. But in actual fact, we are using it wrong.
Nausea comes from the Greek word ‘naurela’ meaning seasickness. Its dictionary definition is “a feeling of discomfort in the stomach with an urge to vomit”. Medically it is used to describe the urge to be sick when the symptoms are not related to a stomach condition.
The vomiting centre in the brain initiates the sensation of feeling the urge to vomit. Exactly what initiates the response is unknown, although scientists currently believe it may through the production of certain chemicals that triggers action in the vomiting centre.
We know that there are 3 areas that commonly are associated with this feeling nauseous; these are the inner ear balance mechanism, the intestinal tracts and also the brain.
The most common ear related condition is travel sickness. This as caused by a confusion between messages to the brain about whether you are moving or not. The sense of equilibrium (like a spirit level) lies in the ear and is usually confirmed as correct by the messages from your eyesight. When these two don’t “agree” whether the body is actually moving or not, it causes nausea, even though the stomach itself is not affected. Children seem to be more susceptible to this trigger, which may be why they are more prone to suffer travel sickness than adults. T
Equally, scientists believe that the nausea feeling that does not cause vomiting when related to a stomach or intestinal issue is the body’s natural mechanism for preventing us eating something dangerous or when our stomachs need to rest. Nausea is a common symptom following a large intake of sugary food – scientists believe the body triggers this response to prevent us eating more and thus giving the body time to produce enough insulin to lower the existing blood sugar level.
Nausea is a common symptom following a brain injury or when there is a foreign body in the brain tissue such as a tumor. Many drugs also seem to invoke the nausea response, particularly aggressive drugs such as chemotherapy.
Recent research has been undertaken to identify the cause of exercise-induced nausea – the feeling of sickness that many people get after taking part in vigorous exercise. A study of 20 volunteers conducted at Nyago University in Japan found more people felt nauseous when exercising after they had eaten. A possible reason for this could be the increased levels of endorphins in a person’s body, which are released while exercising. Endorphins have been associated with nausea and vomiting before, but not fully supported at this stage without further research.
Whatever the cause, nausea can be lessened often by drinking water in small amounts, resting and avoiding solid food. More prolonged nausea without an obvious trigger and when associated with actual vomiting should always be investigated by medical staff as nausea can be indicative of underlying conditions.