“It’s Easier Abroad”: What Our Members Are Saying About Diverticulitis And This Week’s Heatwave

This article does not constitute medical advice. If you have symptoms of diverticulitis or are concerned about your health, please seek guidance from a qualified medical practitioner. This article is based on anonymised discussions from our Diverticulitis Club group on Facebook.

There is no firm evidence that heat itself directly triggers a diverticulitis flare. What a heatwave does change, though, is almost everything around the condition: how much you drink, what you eat, how active you are, how much sun you get, and how well you sleep. Several of those factors are already linked to the well established summer pattern researchers see in diverticulitis admissions, and what our members reported this week lines up closely with that picture.

As the current heatwave took hold across the UK, we asked the group a simple question: is the heat a trigger, and what actually helps? More than a hundred replies later, the answers were far more interesting than a simple yes or no.

Why This Week’s Heatwave Made Us Ask The Question

This week brought one of the most serious heat warnings the UK’s Met Office has ever issued. A Red Extreme Heat Warning, only the second of its kind, covered parts of central and southern England and Wales, with forecasters expecting temperatures to reach the high 30s and potentially close in on the UK’s June record of 35.6°C, set back in 1976 and 1957 (update – it was beaten by a recorded temparature of 36.1 in Hampshire). The only previous Red warning was issued in July 2022, when the UK recorded its highest ever temperature of 40.3°C.

What has made this spell feel especially oppressive is humidity. Forecast dew points of around 22°C this week are far higher than the single figure dew points recorded during the dry heat of July 2022, and high humidity makes it much harder for the body to cool itself through sweating. Several nights have also stayed above 20°C, so called tropical nights, giving little chance to recover before the next hot day begins. The UK Health Security Agency issued a run of Yellow, Amber and Red Heat Health Alerts to reflect the risk.

There is also a simple, often overlooked reason hot weather hits the UK harder than similar temperatures elsewhere. British homes are built to retain heat for our normally cool, damp climate, air conditioning is rare, and our weather systems tend to be more humid than in much of mainland Europe. Climate scientists have pointed out that 30°C in England can feel far more punishing than the same reading somewhere used to it, such as the southern United States.

Is Heat Actually A Trigger, Or Is It Everything Else That Comes With It?

Researchers have noticed a summer peak in diverticulitis admissions for some time. One widely cited study (Adler JT, Chang DC, Chan AT, Faiz O, Maguire LH) compared hospital data from the United Kingdom, the United States and Australia, and found a consistent rise in admissions during each country’s own summer months, even though Australia’s summer falls in the opposite half of the year. The researchers suggested a shared seasonal risk factor rather than heat alone: changes in diet, dehydration, reduced physical activity, altered bowel motility, or seasonal dips in vitamin D have all been proposed, though the exact mechanism is still not fully understood.

A separate, larger review published in 2026 reached a similar conclusion. Researchers from the University of Sydney analysed more than a million recorded cases of diverticulitis across several continents and found rates were up to 27 per cent higher in summer and autumn than in winter. The lead researcher pointed to dehydration in hot weather, more processed food and less fibre eaten at social occasions such as barbecues, and lower vitamin D from reduced sun exposure outside the warmer months as plausible contributors, while being clear that more research is needed to confirm exactly why.

None of this means heat itself is the villain. It means the things a heatwave changes about daily life, fluid intake, food choices, activity levels and sleep, are the same things already known to influence diverticulitis risk. That is a useful distinction, and it matches what members described this week far better than a simple “heat causes flares” headline would.

“Less Stress, Less Routine”: Why Some Members Feel Better Away From Home

Graham Sinclair, who lives in Aberdeenshire, told the group he barely notices any symptoms while on holiday in Lanzarote, even when he is eating and drinking more freely than he would at home. It is only once he is back in his normal routine, he said, that the aches return. Several members agreed that being away from the pressures of daily life, rather than the temperature itself, seemed to make the bigger difference.

Barry Tippett, in Northern Ireland, said much the same in his own way: the heat does not bother his gut at all, and after months of grey, wet weather he finds the sun genuinely good for his mood and his digestion.

Not everyone shared that experience. Wendy Clemson described a flare that started while she was on holiday in Turkey, in similarly hot conditions to those Graham described in Lanzarote. Her experience is a useful reminder that any single factor, sun, stress, diet or travel, rarely tells the whole story, and that individual triggers genuinely vary from person to person.

“It’s The Humidity That Is Hard To Cope With”: What’s Actually Helping Members This Week

Whatever role heat plays in triggering symptoms, staying cool, hydrated and comfortable matters for anyone living with diverticulitis, particularly those managing inflammation or recovering from a flare. Here is what members said is working for them.

• Cooling pulse points: several members, including Susan Field and Jan McKee, run cold water over their wrists and the sides of their neck to bring their temperature down quickly.
• Cold feet, cool body: Carol Fenwick suggested sitting with your feet in a bowl of cold water.
• Wet towel and a fan: a combination recommended by both Craig Simmons in Queensland and Debbie B in Perth, who also pointed out how few public buildings in England have air conditioning compared with Australia.
• Something cold on the back of the neck: Maria Jennings ties an ice pack in a cloth and rests it there.
• Electrolytes and coconut water: mentioned independently by Janet Brennan and Andie Robson as an easy way to stay hydrated without overdoing plain water.
• Cool, low effort foods: Alison Lund recommended yoghurt, cottage cheese and other cold foods that need no cooking.
• A cool shower instead of a swim: Anna Szabo, writing from New Zealand’s winter, said cool showers work well when a pool or beach is not an option.
• Managing the house, not just the body: Susan Field’s tip of closing curtains and blinds on the sunny side of the house and opening windows on the shady side, then swapping as the sun moves round, was echoed by several other members.
• The basics: a sunhat and sunscreen (Eileen Taverner), and sticking to water rather than alcohol (Jan McKee).

For more general guidance on staying safe in hot weather, the NHS has practical advice on how to cope in hot weather.

“I Can No Longer Regulate My Body Temperature”: When Heat Is Harder For Some Members

Not every member finds heat easy to manage, even setting diverticulitis aside. One member explained that since cancer treatment a few years ago, she has lost much of her ability to regulate her own body temperature, and now also lives with a long-term lung condition that makes hot, humid air far harder to cope with than it used to be. Another member, who lives with several autoimmune conditions, said two ceiling fans and a steady supply of iced drinks have become essential, where they were once just a nice to have.

This matches official guidance closely. The NHS specifically flags people with long-term heart, lung, kidney or mobility conditions, along with those on multiple medications, as being at greater risk during hot weather, and has detailed advice on recognising and responding to heat exhaustion and heatstroke if symptoms develop.

Is The Same Pattern Seen Outside The UK?

The group spans lots of countries and, this week, several seasons. Rachel Peake, in the Arizona desert, described temperatures of 108°F (42°C) as simply part of summer, while Wanda Harwood in Oklahoma said she has never adjusted well to the heat there despite living with it every year. Meanwhile Anna Szabo in New Zealand is in the middle of winter, a useful reminder that “the heatwave” is a very local experience even within one Facebook group.

What came through clearly, regardless of climate, was that the basic coping strategies repeat: hydration, shade, cooling specific parts of the body, and managing the home environment rather than just the body. Members in naturally hot climates, including Craig Simmons and Debbie B in Australia, also noted that buildings there are simply built and equipped for heat in a way British housing is not, which goes some way to explaining why a “mild” UK heatwave can feel worse than a much hotter day somewhere used to it.

Key Takeaways

• There is no direct evidence that heat itself triggers diverticulitis flares.
• Diverticulitis admissions do show a well documented summer peak in both the UK and countries with opposite seasons, most likely linked to dehydration, dietary changes, reduced activity and seasonal vitamin D dips rather than heat alone.
• Several members felt better away from their normal routine, suggesting stress and lifestyle changes may matter more than temperature for some people.
• Individual experience varies considerably. Some members flared while travelling in similar heat to others who felt fine.
• Members with other long-term conditions, including heart, lung and autoimmune conditions, need extra care in hot weather, in line with NHS guidance.
• Practical cooling strategies, cold water on pulse points, electrolytes, shade and a cool home, were the most consistently useful tips shared by the group.

Frequently Asked Questions

More Reading

What Age Do People Get Diverticulitis?

Can Stress Trigger Diverticulitis Symptoms?

How Can Diverticulosis Be Prevented?

How Long Will A Diverticulitis Flare Up Last?

What Does Diverticulitis Pain Feel Like?

You’re Not Alone In Wondering About This

As one member put it, it is reassuring just to see that other people are asking the same questions. If this week’s heatwave has left you wondering whether your symptoms are connected to the weather, your routine, your diet, or something else entirely, you are far from alone, and you are also in a good position to find out. Many members have found that keeping a simple food and symptom diary through unusual weeks like this one, hot, cold, or anything in between, is the easiest way to spot their own patterns over time.

You can start your own food and symptoms diary here, or share your own heatwave experience with the group in our Living With Diverticulitis forum.

This article does not constitute medical advice. Please consult a qualified medical practitioner for any personal health concerns.