From the Guidelines
Night sweats are considered episodes of excessive sweating during sleep that are severe enough to soak through sleepwear and bedding, even in a cool room, and are often associated with an underlying medical condition. Normal sweating is a natural bodily function that helps regulate temperature, typically occurring during physical activity, hot environments, or stressful situations. It usually affects the whole body and stops when the trigger is removed. In contrast, night sweats are characterized by their intensity, often waking a person from sleep, and may be accompanied by flushing or heart palpitations. According to the Annals of Oncology 1, unexplained fever, drenching night sweats, or loss of weight can be indicative of a serious underlying condition. Some common causes of night sweats include:
- Hormonal changes, such as menopause
- Infections
- Medications, including antidepressants and hormone treatments
- Anxiety disorders
- Hypoglycemia
- More serious conditions like lymphoma or tuberculosis, as indicated by symptoms such as unexplained fever of >38°C, drenching night sweats, or loss of >10% body weight within 6 months 1. If night sweats occur regularly, disrupt sleep, or are accompanied by other symptoms, medical evaluation is recommended to identify and address the underlying cause.
From the Research
Normal Sweating
- Normal sweating is a natural process that helps regulate body temperature and eliminate waste products 2.
- Eccrine glands, which are responsible for sweating, do not adapt to increase excretion rates or concentrate sweat fluid through vasopressin-mediated water reabsorption 2.
- Sweat composition can vary depending on individual factors, but it is not currently a reliable biomarker for human physiology 2.
Night Sweats
- Night sweats, also known as nocturnal hyperhidrosis, can be a symptom of various underlying conditions, including hormonal changes, infections, and certain medications [no direct evidence from provided studies].
- Hormone replacement therapy (HRT) has been studied in relation to various health outcomes, including cancer risk and immune system function [(3,4,5)], but its direct relation to night sweats is not explicitly mentioned in the provided studies.
- Some studies suggest that HRT may have an impact on lymphoid neoplasms and immune system function [(3,4,5)], but more research is needed to fully understand its effects.