No, you’re not imagining it. People really are more likely to poo in the morning, shortly after breakfast. Researchers have actually studied this.

But why mornings? What if you tend to poo later in the day? And is it worth training yourself to be a morning pooper?

To understand what makes us poo when we do, we need to consider a range of factors including our body clock, gut muscles and what we have for breakfast.

Here’s what the science says.

So morning poos are real?

In a UK study from the early 1990s, researchers asked nearly 2,000 men and women in Bristol about their bowel habits.

The most common time to poo was in the early morning. The peak time was 7-8am for men and about an hour later for women. The researchers speculated that the earlier time for men was because they woke up earlier for work.

About a decade later, a Chinese study found a similar pattern. Some 77% of the almost 2,500 participants said they did a poo in the morning.

But why the morning?

There are a few reasons. The first involves our circadian rhythm – our 24-hour internal clock that helps regulate bodily processes, such as digestion.

For healthy people, our internal clock means the muscular contractions in our colon follow a distinct rhythm.

There’s minimal activity in the night. The deeper and more restful our sleep, the fewer of these muscle contractions we have. It’s one reason why we don’t tend to poo in our sleep.

But there’s increasing activity during the day. Contractions in our colon are most active in the morning after waking up and after any meal.

One particular type of colon contraction partly controlled by our internal clock are known as “mass movements”. These are powerful contractions that push poo down to the rectum to prepare for the poo to be expelled from the body, but don’t always result in a bowel movement. In healthy people, these contractions occur a few times a day. They are more frequent in the morning than in the evening, and after meals.

Breakfast is also a trigger for us to poo. When we eat and drink our stomach stretches, which triggers the “gastrocolic reflex”. This reflex stimulates the colon to forcefully contract and can lead you to push existing poo in the colon out of the body. We know the gastrocolic reflex is strongest in the morning. So that explains why breakfast can be such a powerful trigger for a bowel motion.

Then there’s our morning coffee. This is a very powerful stimulant of contractions in the sigmoid colon (the last part of the colon before the rectum) and of the rectum itself. This leads to a bowel motion.

How important are morning poos?

Large international surveys show the vast majority of people will poo between three times a day and three times a week.

This still leaves a lot of people who don’t have regular bowel habits, are regular but poo at different frequencies, or who don’t always poo in the morning.

So if you’re healthy, it’s much more important that your bowel habits are comfortable and regular for you. Bowel motions do not have to occur once a day in the morning.

Morning poos are also not a good thing for everyone. Some people with irritable bowel syndrome feel the urgent need to poo in the morning – often several times after getting up, during and after breakfast. This can be quite distressing. It appears this early-morning rush to poo is due to overstimulation of colon contractions in the morning.

Can you train yourself to be regular?

Yes, for example, to help treat constipation using the gastrocolic reflex. Children and elderly people with constipation can use the toilet immediately after eating breakfast to relieve symptoms. And for adults with constipation, drinking coffee regularly can help stimulate the gut, particularly in the morning.

A disturbed circadian rhythm can also lead to irregular bowel motions and people more likely to poo in the evenings. So better sleep habits can not only help people get a better night’s sleep, it can help them get into a more regular bowel routine.

Regular physical activity and avoiding sitting down a lot are also important in stimulating bowel movements, particularly in people with constipation.

We know stress can contribute to irregular bowel habits. So minimising stress and focusing on relaxation can help bowel habits become more regular.

Fibre from fruits and vegetables also helps make bowel motions more regular.

Finally, ensuring adequate hydration helps minimise the chance of developing constipation, and helps make bowel motions more regular.

Monitoring your bowel habits

Most of us consider pooing in the morning to be regular. But there’s a wide variation in normal so don’t be concerned if your poos don’t follow this pattern. It’s more important your poos are comfortable and regular for you.

If there’s a major change in the regularity of your bowel habits that’s concerning you, see your GP. The reason might be as simple as a change in diet or starting a new medication.

But sometimes this can signify an important change in the health of your gut. So your GP may need to arrange further investigations, which could include blood tests or imaging.

Vincent Ho, Associate Professor and clinical academic gastroenterologist, Western Sydney University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

When spring arrives, so do warnings about thunderstorm asthma. But a decade ago, most of us hadn’t heard of it.

So where did thunderstorm asthma come from? Is it a new phenomenon?

In 2016, the world’s most catastrophic thunderstorm asthma event took Melbourne by surprise. An increase in warnings and monitoring is partly a response to this.

But there are also signs climate change may be exacerbating the likelihood of thunderstorm asthma, with more extreme weather, extended pollen seasons and a rise in Australians reporting hay fever.

A landmark catastrophe

The first time many Australians heard of thunderstorm asthma was in November 2016, when a major event rocked Melbourne.

During a late night storm, an estimated 10,000 people were rushed to hospitals with severe asthma attacks. With thousands of calls on emergency lines, ambulances and emergency departments were unprepared to handle the rapid increase in people needing urgent medical care. Tragically, ten of those people died.

This was the most catastrophic thunderstorm asthma event in recorded history and the first time deaths have ever occurred anywhere in the world.

In response, the Victorian Department of Health implemented initiatives, including public awareness campaigns and improvements to health and emergency services, to be ready for future thunderstorm asthma events.

A network of pollen monitoring stations was also set up across the state to gather data that helps to predict future events.

A problem for decades

While this event was unexpected, it wasn’t the first time we’d had thunderstorm asthma in Australia – we’ve actually known about it for decades.

Melbourne reported its first instance of thunderstorm asthma back in 1984, only a year after this phenomenon was first discovered in Birmingham in the United Kingdom.

Thunderstorm asthma has since been reported in other parts of Australia, including Canberra and New South Wales. But it is still most common in Melbourne. Compared to any other city (or country) the gap is significant: over a quarter of all known events worldwide have occurred in Melbourne.

Why Melbourne?

Melbourne’s location makes it a hotspot for these kinds of events. Winds coming from the north of Melbourne tend to be dry and hot as they come from deserts in the centre of Australia, while winds from the south are cooler as they come from the ocean.

When hot and cool air mix above Melbourne, it creates the perfect conditions for thunderstorms to form.

Northern winds also blow a lot of pollen from farmlands into the city, in particular grass pollen. This is not only the most common cause of seasonal hay fever in Melbourne but also a major trigger of thunderstorm asthma.

Why grass pollen?

There’s a particular reason grass pollen is the main culprit behind thunderstorm asthma in Australia. During storms there is a lot of moisture in the air. Grass pollen will absorb this moisture, making it swell up like a water balloon.

If pollen absorbs too much water whilst airborne, it can burst or “rupture,” releasing hundreds of microscopic particles into the air that can be swept by powerful winds.

Normally, when you breathe in pollen it gets stuck in your upper airway – for example, your nose and throat. This is what causes typical hay fever symptoms such as sneezing or runny nose.

But the microscopic particles released from ruptured grass pollen are much smaller and don’t get stuck as easily in the upper airway. Instead, they can travel deep into your airways until they reach your lungs. This may trigger more severe symptoms, such as wheezing or difficulty breathing, even in people with no prior history of asthma.

So who is at risk?

You might think asthma is the biggest risk factor for thunderstorm asthma. In fact, the biggest risk factor is hay fever.

Up to 99% of patients who went to the emergency department during the Melbourne 2016 event had hay fever, while a majority (60%) had no prior diagnosis of asthma.

Every single person hospitalised was allergic to at least one type of grass pollen. All had a sensitivity to ryegrass.

Is thunderstorm asthma becoming more common?

Thunderstorm asthma events are rare, with just 26 events officially recorded worldwide.

However there is evidence these events could become more frequent and severe in coming years, due to climate change. Higher temperatures and pollution could be making plants produce more pollen and pollen seasons last much longer.

Extreme weather events, including thunderstorms, are also expected to become more common and severe.

In addition, there are signs rates that hay fever may be increasing. The number of Australians reporting allergy symptoms have risen from 15% in 2008 to 24% in 2022. Similar trends in other countries has been linked to climate change.

How can I prepare?

Here are three ways you can reduce your risk of thunderstorm asthma:

• stock up on allergy medication and set up an asthma action plan with your GP
• check daily pollen forecasts for the estimated pollen level and risk of a thunderstorm asthma event in your local area
• on days with high pollen or a high risk of thunderstorm asthma, spend less time outside or wear a surgical face mask to reduce your symptoms.

Kira Morgan Hughes, PhD Candidate in Allergy and Asthma, School of Life and Environmental Sciences, Deakin University

This article is republished from The Conversation under a Creative Commons license. Read the original article.