All About Sweat

Sweating is a process of thermoregulation – the body’s ability to regulate its temperature. However, the body can also produce sweat when we are stressed, emotional or anxious.

The triggers of sweaing:¹

• Heat / temperature
• Exercise
• Emotions (e.g. stress, anxiety)
• Hormonal changes
• Food
• Infection
• Signal
  

Temperature regulation¹

Under normal conditions our body temperature is in a state of heat balance or ‘equilibrium’.  If our body temperature increases due to heat from external surroundings (such as warm weather or a hot room) or internally from exercise or strenuous activity, our body will work to cool us back down by the process of sweating.  The sweat on the surface of the body then evaporates, which helps to cool us down and bring our temperature back to normal. However, sweat in the armpits (also known as axillary sweating), tends not to evaporate as easily as sweating on the rest of the body, and therefore it does not play a big role in keeping us cool.

Exercise¹

Exercise causes our internal heat input to rise, triggering the body to produce sweat to cool us down and bring our body back into a state of heat equilibrium.  Sweating can continue even after exercise, until the body’s temperature is back to normal.

Emotions¹

Sweating is a normal occurrence when we experience strong emotions or stress, irrespective of temperature. This type of sweating is often referred to as ‘cold sweats’. Emotions such as fear, anxiety or stress trigger the release of the hormone adrenaline and it is this rush of adrenaline which sets off a cascade of events in the body, one of which is sweating.

Hormonal changes¹

Puberty marks the onset of normal sweating from the apocrine glands, but other hormonal changes, such the menopause can also cause episodes of sweating. Hormonal changes during the menopause lead to a change in the body’s temperature, setting off symptoms such as hot flushes, night sweats and heat intolerance. Sweating during the menopause can be so severe that it can drench clothes and bed sheets during night time. These menopausal symptoms of sweating can greatly impact a woman’s quality of life. 

Eating can cause sweat secretion as the body’s temperature increases due to a rise in the body’s metabolism. Some people find that hot and spicy food can cause an episode of sweating, especially on the face, scalp and neck. This happens because the substance capsaicin, which is found in spicy food, stimulates sensors in the mouth which are normally involved in thermoregulation and sweating

Infection²

Our immune system reacts to a bacterial or viral infection by producing antibodies to fight infection and kill pathogens (bacteria or viruses). This immune system activity causes a rise in body temperature and / or a fever, which causes us to sweat. A fever goes through various stages to fight infection; profuse sweating happens at the final stages of fever when the body is working hard to cool itself down from the excess heat produced to fight the infection and bring itself back down to a normal temperature.

Pheromones¹

Sweat produced from the apocrine gland is thought to contain certain chemical ‘signals’, known as pheromones, which aid in the communication of emotions, such as fear, anxiety or attraction.  Pheromones are also implicated in attracting the opposite sex and causing women’s menstrual cycles to synchronise.

1. Unilever. Facts about Sweating
2. National Cancer Institute. Fever Sweats and Hot Flashes http://www.cancer.gov/cancertopics/pdq/supportivecare/fever/Patient/page2  (last        accessed 15.12.12)