How can you tell if your sweating is excessive?

Perspiration is a normal and essential physiological process. It allows the body to maintain a stable core temperature, around 37°C (98.6°F), by dissipating heat produced by metabolism or accumulated from environmental conditions.

Aside from sustained physical exertion or high heat, the body produces on average about one liter of sweat per day.

For this reason, there is no simple, universal threshold that makes it possible to state from what amount sweating becomes “abnormal.” In practice, we instead refer to hyperhidrosis when sweat is produced in quantities that exceed the actual needs of thermoregulation and becomes a source of everyday discomfort. In other words, sweating is considered excessive not only because of its intensity, but also because of itsfunctional, social, or emotional impact. Several concrete signs may suggest hyperhidrosis:

• Hands that become so moist that they interfere with simple movements, like holding a steering wheel, using a keyboard, handling a pen, or shaking someone’s hand.

• Clothing that becomes wet quickly, without requiring particular effort or excessive heat.

• The need to shower or change clothes several times in the same day.

• Discomfort related to a body odor from perspiration.

This bothersome symptom is actually one of the best indicators of excessive sweating. When perspiration starts to affect quality of life, it raises the question of whether the person might be experiencing hyperhidrosis.

To better understand whether sweating is excessive, it is also helpful to observe how it is distributed over the body. In most cases, hyperhidrosis is described as localized, meaning it affects certain specific areas, most often the armpits, the palms of the hands, the soles of the feet, or the face. Conversely, more rarely, sweating can be generalized and involve the entire body. This form represents about 10% of cases and can occur at any age.

It should also be noted that a distinction is made between primary and secondary hyperhidrosis.

Primary hyperhidrosis is the most common form. It generally corresponds to localized sweating without any clearly identified medical cause. It is thought to be linked to a hyperactivity of the sympathetic nervous system, which overstimulates the sweat glands, even when there is no real need. Certain factors can trigger or worsen episodes, such as stress, strong emotions, heat, physical exertion, consumption of alcohol, or spicy foods. A genetic predisposition is also suspected, with a substantial proportion of patients having a family history.

In contrast, secondary hyperhidrosis is linked to an identifiable cause. It is often generalized, but it can also be localized in certain cases. It may be associated with various conditions or diseases, such as menopause, overweight, anxiety disorders, the use of certain medications, or illnesses such as hyperthyroidism, certain infections, cancers, or Parkinson’s disease.

Several tips can help you sweat less. If these are not sufficient, do not hesitate to consult a physician, who can help you find an appropriate solution.

• BREWER J. D. & al. Management of hyperhidrosis. Clinical, Cosmetic and Investigational Dermatology (2014).

• CHA J. & al. The etiology, diagnosis, and management of hyperhidrosis: A comprehensive review. Journal of the American Academy of Dermatology (2019).

• JEMEC G. & al. How to diagnose and measure primary hyperhidrosis: A systematic review of the literature. Clinical Autonomic Research (2021).