As we get older, a good night's rest becomes far more attractive than a late night out. What’s more, the quality of our sleep begins to make a big difference in our day-to-day lives. A restful night of uninterrupted sleep can give your whole day a boost, while a warm, sweaty night of tossing, turning and pillow-flipping can leave you unproductive and irritable to next day.

There are many reasons why you might experience night sweats as you get older — menopause being just one of them. Below, we’ll outline some helpful insights about what on earth night sweats are, and why they happen, to get you on the path to a cooler, more restful night’s sleep.

What exactly are night sweats?

Night sweats, also known as sleep hyperhidrosis, are episodes of sweating at night that leave your clothing and sheets drenched in sweat. Night sweats are not the same as overheated sleeping (simply feeling over-warm in bed) — they are severe hot flushes that occur at night and can be due to a variety of reasons, including the menopause.[1] While most night sweats are caused by non-life threatening issues, they can also be a symptom of a serious underlying condition, so it's always best to speak to your doctor about them, especially if they recur often. 

What causes night sweats?

There are several reasons why you could be having night sweats, including many reasons unrelated to the menopause. So when should you be concerned about night sweats? Below we’ve outlined just a few of the causes of night sweats, and what you can do about them.

Hypoglycaemia 

Hypoglycaemia, sometimes referred to as a "hypo," occurs when the level of sugar (glucose) in your blood drops too low. While it can happen to anyone, people with insulin-dependent diabetes are particularly prone to an attack, typically if they take too much insulin, miss a meal or exercise too hard.

If a hypoglycemic attack occurs in the night, you may experience night sweats and wake up feeling tired, dizzy or shaky. Hypoglycemia can be dangerous if it's not treated immediately, but you should be able to manage it easily by consuming something sugary like juice. If you have diabetes and have a home testing kit to check your glucose level, you should do so immediately, administer your glucagon injection if needed.[2]

Hyperthyroidism 

Hyperthyroidism (also known as an overactive thyroid or thyrotoxicosis) is a condition where the thyroid gland produces too much of the thyroid hormones which affect many of your body's functions such as heart rate and body temperature. 

It can affect anyone, but is around 10 times more common in women, particularly women in their 40s, so night sweats caused by hyperthyroidism are often mistaken as being caused by the onset of the menopause. [3] Hyperthyroidism and other hormone imbalances can not only cause night sweats, but can also result in potentially severe complications that need further treatment, so it's best to get your symptoms fully investigated. 

Illness or infection

If you are ill, particularly with fever or the flu, night sweats could occur as a result. On the more critical side of the spectrum, infections such as tuberculosis. endocarditis (inflammation of the heart valves) and osteomyelitis (inflammation in the bones) are also known to trigger night sweats. [4] [5] In rare cases, night sweats can also be an early indication of cancer — in particular lymphoma and leukemia are linked with night sweats. [6] If you suspect you have any of these conditions, it is essential to see your doctor right away. However, it’s important not to become overwhelmed with this, as it’s far less common than other causes of night sweats. Instead, be sure to speak to your GP if you consistently experience night sweats.

Medications

While you might think the medicines are meant to help alleviate signs of sickness, many of their side-effects can include symptoms such as night sweats. For instance, medicine taken to lower fever such as aspirin and acetaminophen can sometimes cause excessive sweating as they work to reduce your body temperature. Other medications, including niacin, tamoxifen, hydralazine, and nitroglycerine, can cause hot flushes that may be mistaken for night sweats. [7] If you think your medication may be interfering with your sleep, it’s important to speak to your doctor as soon as you notice these symptoms to discuss alternative treatment.

Stress and anxiety

There are certain elements of your lifestyle and mental health that may cause night sweats. Anxiety activates a stress response, which temporarily increases the body’s metabolism, respiration, and perspiration. As such, periods of high stress can lead to increased sweating, including at night. You may find yourself waking up with drenched sheets when your stressful work or family life has been particularly intense or draining. Although it's easier said than done, cutting down on your workload can sometimes be all the remedy you need to reduce night sweats. However, if they persist, why not take some time out for yourself with these tried and true mindfulness techniques.

Menopause

When night sweats occur due to the menopause, they are caused by the changing levels of oestrogen in our bodies. Oestrogen plays many roles in the human body, including regulating our body temperature (thermoregulation). So when oestrogen is in flux and your temperature increases, your body reacts by sweating to prevent overheating.[8] If you are experiencing night sweats due to the menopause, you may also experience other telltale signs of the menopause along with them, such as hot flushes, vaginal dryness, and menstrual irregularity.

The science behind a good night’s sleep

Don’t just leave it up to chance, or simply play it by ear, good sleep is a science. If night sweats are keeping you up in the small hours, check out our range of Anti-Flush clothing and cooling bedding expertly engineered to keep you cool and fresh well into the night.

For more information on the ups and downs of night sweats, and what you can do to alleviate their symptoms, simply visit our Menopause Guide.

1. WedMd, Causes of Night Sweats (2018). Available at: https://www.webmd.com/menopause/guide/8-causes-of-night-sweats. [Accessed 27 Jan 2020]
2. NHS UK, Hypoglycaemia (2019). Available at: https://www.nhs.uk/conditions/low-blood-sugar-hypoglycaemia/. [Accessed 27 Jan 2020]
3. NHS UK, Hyperthyroidism (2019) Available at:  https://www.nhs.uk/conditions/overactive-thyroid-hyperthyroidism/. [Accessed 27 Jan 2020]
4. Medical News Today, What to know about Night Sweats (2017). Available at: https://www.medicalnewstoday.com/articles/296818.php#causes. [Accessed 27 Jan 2020]
5. Causes of Night Sweats (2018). Available at: https://www.webmd.com/menopause/guide/8-causes-of-night-sweats. [Accessed 27 Jan 2020]
6. MedicineNet, Night Sweats Causes, Remedies, Treatments (no date). Available at: https://www.medicinenet.com/night_sweats/article.htm. [Accessed 27 Jan 2020]
7. MedicineNet, Night Sweats Causes, Remedies, Treatments (no date). Available at: https://www.medicinenet.com/night_sweats/article.htm. [Accessed 27 Jan 2020]