The temperature difference between happy tears and tears of sadness is primarily due to their composition and the emotional context in which they are produced.
- Composition of Tears: Tears are not a singular fluid; they consist of various components, including water, salt (sodium chloride), enzymes, oils, and antibodies. Tears produced when we are cutting onions or experiencing eye irritation are known as basal tears. These tears help keep our eyes moist and lubricated and have a similar composition to happy tears.
However, emotional tears, whether they are tears of joy or tears of sadness, contain additional substances that are not present in basal tears. Emotional tears contain higher levels of stress hormones and proteins associated with emotions, which are released when we experience intense feelings, be it happiness, sadness, or any other strong emotion.
Autonomic Nervous System Response: When we experience strong emotions, our autonomic nervous system is activated. This system controls various involuntary bodily functions, including tear production. When we cry due to emotional reasons, the body responds to the emotional stimulus, leading to the production of tears.
Blood Flow and Temperature: Emotional tears are thought to be warm because they are associated with an increase in blood flow to the lacrimal glands. The lacrimal glands are responsible for tear production, and the increased blood flow in this area may contribute to the warmth of emotional tears.
On the other hand, tears produced in response to eye irritation or cutting onions are not influenced by the autonomic nervous system in the same emotional way. These tears are generally more similar in temperature to the rest of the body.
It's important to note that the temperature difference between happy and sad tears is not always easily detectable, and it can vary from person to person. The warmth of emotional tears is just one of the many fascinating aspects of human physiology and emotion.