Pioneering new study tests how a simple ice slushy could protect against heat exhaustion for the elderly and vulnerable

With extreme heat now one of the biggest weather-related threats to human health, researchers at the University of Brighton are turning their attention to a little-researched solution for heat-related illness: ice slurries – which are the same as slushies sold in shops but without the flavourings. 

This pioneering research aims to determine whether drinking ice slurry – a semi-frozen beverage that cools the body faster than water – can provide a new preventative solution to gut-related health issues which can exacerbate the effects of extreme heat, particularly in older and vulnerable populations.    

We all know how refreshing a cold drink can feel after being out in the heat – but this new research focuses on the benefits of cooling the body before heat exposure. While many people understand the importance of staying cool in hot weather, this new research will explore a critical and often overlooked link between heat exposure and gut health. When the body overheats, its natural gut barrier can weaken, allowing harmful bacteria and toxins to leak into the bloodstream. 

This “leaky gut” effect plays a key role in triggering heat stroke, one of the most dangerous forms of heat illness. Older adults are particularly vulnerable, with age-related changes in gut integrity putting them at even greater risk when exposed to high temperatures. 

Now, researchers at Brighton are investigating whether drinking ice slurry could help stop this dangerous chain reaction before it starts. Taking place at the University’s Environmental Extremes Lab between April and June, the study looks at how drinking a slushy-style ice mixture affects core body temperature and gut health during heat exposure.  

In practical terms, it raises questions like: if someone drinks a slushy before heading out to garden on a hot day, could it protect them from becoming unwell? Or perhaps, if older adults consume a cooling beverage before taking a walk on a warm afternoon, could it reduce their risk of heatstroke? 

This innovative research hopes to pave the way for more effective, accessible and low-cost strategies to protect individuals in hot environments. The findings could help shape future advice for vulnerable groups during periods of extreme heat and offer new insights into how we can stay safer and healthier in a warming world. 

Gregor Eichhorn, Principal Investigator and PhD student at the University’s School of Education, Sport and Health Sciences, said: “Heat illnesses are a growing concern. We hope that our findings can lead to practical solutions to prevent heat-related health issues, especially for those who are most vulnerable. This study is not just about understanding how to manage heat exposure but also about developing strategies that could be used in everyday situations to ensure people stay safe and healthy.” 

Dr Neil Maxwell, who leads the Environmental Extremes Lab at the University of Brighton, said: “We know that heat can increase gut permeability, and that this effect is more pronounced in older people. But we don’t yet know how best to offset that risk. This study is testing whether a very simple strategy – drinking something cold – can actually help prevent some of the harmful effects of heat stress.” 

This research is supported by the University’s state-of-the-art Environmental Extremes Lab, which is equipped with a new dual-capacity environmental chamber – one of the only chambers of its kind in the UK – that was recently funded by the Wolfson Foundation. In April, representatives from the Wolfson Foundation visited the lab to see first-hand how the new chamber is advancing research and enriching the student experience. 

 The chamber can simulate extreme temperatures ranging from -20°C to +50°C and can also replicate high-altitude environments, such as those close to the height of Mount Kilimanjaro. This advanced facility allows researchers to conduct more accurate and comprehensive studies, providing deeper insights into how the body responds to extreme heat and environmental stressors. 

This latest project adds to the lab’s work in identifying practical, accessible ways to improve health and performance during environmental stress and reflects the University of Brighton’s ongoing commitment to climate resilience, public health, and applied science that makes a difference in everyday lives. 

If you’re interested in taking part or to find out more about the research, please contact: g.eichhorn@brighton.ac.uk