Many families and individuals with Prader-Willi syndrome (PWS) notice that temperature doesn’t always “behave” in the way you might expect.
Someone with PWS might become unusually hot in warm weather, struggle to cool down, or seem cold when others feel comfortable. Some people also experience episodes where their temperature rises or falls without an obvious cause, such as illness.
For some, this can come with a general feeling of being unwell, tired, or fatigued — something many families will recognise, even if it’s hard to explain exactly why.
This idea of temperature dysregulation is something that is becoming more widely recognised in PWS. While it may not be as well known as other aspects of the condition, research is beginning to show that it is a genuine and important part of how PWS can affect the body.
How does the body normally regulate temperature?
The human body works hard to keep its internal temperature within a narrow and stable range, regardless of what’s happening outside.
A small but important part of the brain called the hypothalamus acts as the body’s thermostat. It helps coordinate responses such as:
- sweating
- shivering
- thirst
- changes in blood flow to the skin
Together, these processes allow the body to cool down or warm up as needed.
In PWS, the hypothalamus does not function in the typical way. This area of the brain is already known to play a key role in hunger, sleep, and hormone regulation, and researchers believe it is also central to understanding temperature regulation differences.
What is temperature dysregulation?
Temperature dysregulation simply means difficulty keeping body temperature within a typical range.
This can include:
- Becoming unusually hot in warm conditions
- Difficulty cooling down once overheated
- Experiencing lower-than-expected body temperature
- Temperature changes that don’t seem to match the environment
Importantly, research has shown that both overheating (hyperthermia) and low body temperature (hypothermia) can occur in people with PWS.
What has research found?
Although this area has not been studied as extensively as some other aspects of PWS, a growing number of studies over the past two decades point to temperature dysregulation being relatively common. (We’ve listed some at the bottom of this blog)
Recent research suggests that around one in five children and young people with PWS have experienced episodes of temperature dysregulation. This indicates it may be more common than previously recognised.
Other studies and case reports describe individuals developing high body temperatures without a clear cause, such as infection. Researchers believe this may reflect differences in how the body controls temperature internally, rather than illness alone.
At the same time, some studies have found that people with PWS may not always develop a typical fever during infection. This means that temperature is not always a reliable indicator of illness, which can make things more complex to interpret.
Together, these findings suggest that temperature regulation in PWS does not always follow the usual patterns seen in the general population.
Why might this happen?
Researchers are still working to fully understand why temperature dysregulation occurs in PWS, but several possible explanations have been proposed.
One key area is hypothalamic function. Because the hypothalamus acts as the body’s thermostat, differences in how it works are thought to play an important role.
Another area of interest is the autonomic nervous system, which controls automatic processes such as heart rate, sweating, and blood vessel responses — all of which are involved in regulating temperature.
There is also some evidence that people with PWS may perceive temperature differently, which could make it harder to recognise when they are becoming too hot or too cold.
As with many aspects of PWS, it is likely that more than one of these factors is involved.
What questions remain?
While awareness of temperature dysregulation in PWS is increasing, there is still much we don’t yet fully understand.
Researchers are continuing to explore:
- Why some people with PWS are more affected than others
- Whether temperature regulation differs between genetic subtypes
- How temperature regulation may change with age
- The role of hormones and the autonomic nervous system
- Whether specific approaches could help improve thermoregulation
Looking ahead
Temperature regulation may not receive the same level of attention as appetite, behaviour, or sleep in PWS, but growing evidence suggests it is an important part of the condition for many individuals.
By continuing to study how the hypothalamus and related systems work in PWS, researchers hope to build a clearer understanding of why these differences occur.
Each new study helps to add another piece to the puzzle — bringing us closer to understanding the full picture of how PWS affects the body.
What does this mean for people with PWS now?
Finally, it’s important to remember that, like many aspects of Prader-Willi syndrome, temperature regulation exists on a spectrum. Not everyone with PWS will experience these difficulties, and for those who do, the extent and impact can vary widely.
Awareness is key. Knowing that temperature dysregulation can be part of PWS helps ensure that the people around an individual — including schools, carers and residential settings — understand what might be happening and why.
During periods of warmer weather, such as the heatwaves increasingly seen across the UK, this information is helpful context rather than a cause for alarm. Instead, it highlights the importance of recognising individual differences and ensuring that those supporting people with PWS are aware that temperature may not always be regulated in the usual way.
- Preliminary Report on Temperature Dysregulation in a Cohort of Youth with Prader- Willi Syndrome (2025) https://pmc.ncbi.nlm.nih.gov/articles/PMC12452688/
2. Prader-Willi Syndrome: A Review of Clinical, Genetic, and Endocrine Findings (2015) https://pmc.ncbi.nlm.nih.gov/articles/PMC4630255/
3. Thermal Dysregulation in Prader-Willi Syndrome (2016) https://pmc.ncbi.nlm.nih.gov/articles/PMC4932422/
4. Characteristics of Hyperthermia and its Complications in Patients with Prader-Willi Syndrome (2005) https://onlinelibrary.wiley.com/doi/10.1111/j.1442-200X.2005.02124.x
5. Oxytocin’s Regulation of Thermogenesis may be the link between Prader-Willi Syndrome and Obesity (2023) https://www.mdpi.com/1467-3045/45/6/313
6. Staying Safe in the Heat – www.pwsausa.org/staying-safe-in-the-heat/