As we enter the festive season it’s a good time to think about what all those celebratory alcoholic drinks can do to your gut.

Alcohol can interfere with the time it takes for food to go through your gut (also known as the “transit time”). In particular, it can affect the muscles of the stomach and the small bowel (also known as the small intestine).

So, how and why does alcohol make your poos goes weird? Here’s what you need to know.

Diarrhoea and the ‘transit time’

Alcohol’s effect on stomach transit time depends on the alcohol concentration.

In general, alcoholic beverages such as whisky and vodka with high alcohol concentrations (above 15%) slow down the movement of food in the stomach.

Beverages with comparatively low alcohol concentrations (such as wine and beer) speed up the movement of food in the stomach.

These changes in gut transit explain why some people can get a sensation of fullness and abdominal discomfort when they drink vodka or whisky.

How long someone has been drinking a lot of alcohol can affect small bowel transit.

We know from experiments with rats that chronic use of alcohol accelerates the transit of food through the stomach and small bowel.

This shortened transit time through the small bowel also happens when humans drink a lot of alcohol, and is linked to diarrhoea.

Alcohol can also reduce the absorption of carbohydrates, proteins and fats in the duodenum (the first part of the small bowel).

Alcohol can lead to reduced absorption of xylose (a type of sugar). This means diarrhoea is more likely to occur in drinkers who also consume a lot of sugary foods such as sweets and sweetened juices.

Chronic alcohol use is also linked to:

• lactose intolerance
• overgrowth of small bowel bacteria and
• reduced absorption of fats from the pancreas not producing enough digestive enzymes.

This means chronic alcohol use may lead to diarrhoea and loose stools.

How might a night of heavy drinking affect your poos?

When rats are exposed to high doses of alcohol over a short period of time, it results in small bowel transit delay.

This suggests acute alcohol intake (such as an episode of binge drinking) is more likely to lead to constipation than diarrhoea.

This is backed up by recent research studying the effects of alcohol in 507 university students.

These students had their stools collected and analysed, and were asked to fill out a stool form questionnaire known as the Bristol Stool Chart.

The research found a heavy drinking episode was associated with harder, firm bowel motions.

In particular, those who consumed more alcohol had more Type 1 stools, which are separate hard lumps that look or feel a bit like nuts.

The researchers believed this acute alcohol intake results in small bowel transit delay; the food stayed for longer in the intestines, meaning more water was absorbed from the stool back into the body. This led to drier, harder stools.

Interestingly, the researchers also found there was more of a type of bacteria known as “Actinobacteria” in heavy drinkers than in non-drinkers.

This suggests bacteria may have a role to play in stool consistency.

But binge drinking doesn’t always lead to constipation. Binge drinking in patients with irritable bowel syndrom (IBS), for example, clearly leads to diarrhoea, nausea and abdominal pain.

What can I do about all this?

If you’re suffering from unwanted bowel motion changes after drinking, the most effective way to address this is to limit your alcohol intake.

Some alcoholic beverages may affect your bowel motions more than others. If you notice a pattern of troubling poos after drinking certain drinks, it may be sensible to cut back on those beverages.

If you tend to get diarrhoea after drinking, avoid mixing alcohol with caffeinated drinks. Caffeine is known to stimulate contractions of the colon and so could worsen diarrhoea.

If constipation after drinking is the problem, then staying hydrated is important. Drinking plenty of water before drinking alcohol (and having water in between drinks and after the party is over) can help reduce dehydration and constipation.

You should also eat before drinking alcohol, particularly protein and fibre-rich foods.

Food in the stomach can slow the absorption of alcohol and may help protect against the negative effects of alcohol on the gut lining.

Is it anything to worry about?

Changes in bowel motions after drinking are usually short term and, for the most part, resolve themselves pretty efficiently.

But if symptoms such as diarrhoea persist beyond a couple of days after stopping alcohol, it may signify other concerning issues such as an underlying gut disorder like inflammatory bowel disease.

Researchers have also linked alcohol consumption to the development of irritable bowel syndrome.

If problems persist or if there are alarming symptoms such as blood in your stool, seek medical advice from a general practitioner.

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.

It’s the morning after a big night and you’re feeling the effects of too much alcohol.

So it can be tempting to “refresh” and take the edge off a hangover with a swim at the beach, or a dip in the cool waters of your local river or pool.

But you might want to think twice.

The day after heavy drinking can affect your body, energy levels and perception of risk in many ways. This means you’re more likely to drown or make careless decisions – even without high levels of alcohol in your blood.

Alcohol + water + summer = drowning

Alcohol is one of the main reasons why someone’s more likely to die due to drowning. And Australians consume a lot of it, including around the water.

The risk of drowning, and injury, including incidents involving alcohol, dramatically increases over the summer festive period – in particular on public holidays and long weekends.

Among people aged 18 and over who drowned in rivers where alcohol was involved, we found some 40% had a blood alcohol concentration of at least 0.20%. That’s four times the upper legal limit of 0.05% when driving a car on a full licence.

When we breathalysed people at four Australian rivers, we found higher levels of blood alcohol with higher temperatures, and particularly on public holidays.

At the beach, intoxication due to alcohol and/or drugs is involved in 23% of drowning deaths with an average blood alcohol concentration of 0.19%.

How about if you’re hungover?

Getting alcohol out of your body is a relatively slow process. On average, alcohol is metabolised at a rate of 0.015% per hour. So if someone stops drinking at 2am with a blood alcohol concentration of 0.20%, their alcohol levels don’t drop to zero until 4pm the next day.

Although hangovers can vary from person to person, typical symptoms include headache, muscle aches, fatigue, weakness, thirst, nausea, stomach pain, vertigo, irritability, sensitivity to light and sound, anxiety, sweating and increased blood pressure.

As well as feeling a bit dusty, the day after an evening of heavy drinking, you’re not so good at identifying risks and reacting to them.

In a pool, this might mean not noticing it’s too shallow to dive safely. In natural waterways, this might mean not noticing a strong river current or a rip current at the beach. Or someone might notice these hazards but swim or dive in anyway.

In one study, we found that after a four-day Australian music festival where people drank heavily, even people who were sober (no longer had alcohol in their blood) were still affected.

Compared to baseline tests in the lab we ran three weeks before the festival, people who were sober the day after the festival had faster reaction times in a test to gauge their attention. But they made more mistakes. This suggests hangovers coupled with fatigue lead to quicker but more careless behaviour.

In and around water this could be the difference between life and death.

Positive blood alcohol readings, including of alcohol from the night before, are commonly implicated in drowning deaths as a result of risky behaviours such as jumping into the water, both at a river and along the coast. Jumping can cause physical injury or render you unconscious, leading to drowning.

Alcohol, including the day after drinking, can also make drowning more likely for a number of other reasons. It also reduces people’s coordination and reaction times.

What else is going on?

Alcohol makes the blood vessels near your skin open up (dilate). So more blood flows into them, making you feel hot. This means you may stay in colder water for longer, increasing your risk of hypothermia.

Alcohol can even make CPR (cardiopulmonary resuscitation) less effective, should you need to be resuscitated.

Normally, your body controls levels of certain minerals (or electrolytes) in the blood. But electrolyte imbalance is common after heavy drinking, including the day after. It’s the reason why hangover symptoms such as muscle pain can lead to cramps in your arms or legs. This can become dangerous when being in or on the water.

Low blood sugar levels the day after drinking is also common. This can lead to people becoming exhausted more quickly when doing physical activities, including swimming.

Other hazards include cold water, high waves and deep water, all of which your body may not be capable of dealing with if you’re feeling the effects of a big night.

What can we do about it?

Authorities regularly warn about the dangers of alcohol intoxication and being near the water. Young people and men are often targeted because these are the groups more likely to drown where alcohol is involved.

Beaches may have alcohol-free zones. Rivers rarely have the same rules, despite similar dangers. https://www.youtube.com/embed/5Salt-kkGUo?wmode=transparent&start=0 Royal Life Saving urges men to ‘make the right call’ and avoid alcohol around the water.

How to stay safe around water if you’re drinking

So take care this summer and stay out of the water if you’re not feeling your best:

• do your swimming before your drinking
• look out for your mates, especially ones who may have had a few too many or are hungover
• avoid getting back into the water after you’ve drunk alcohol or if you’re not feeling your best the next day.

Amy Peden, NHMRC Research Fellow, School of Population Health & co-founder UNSW Beach Safety Research Group, UNSW Sydney; Emmanuel Kuntsche, Director of the Centre for Alcohol Policy Research, La Trobe University, and Jasmin C. Lawes, Adjunct Senior Lecturer, UNSW Beach Safety Research Group, UNSW Sydney

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