Everyone seems to have a different opinion when it comes to how often towels and bed sheets should be washed. While many people might wonder whether days or weeks is best, in one survey from the United Kingdom, almost half of single men reported not washing their sheets for up to four months at a time.

It’s fairly clear that four months is too long to leave it, but what is the ideal frequency?

Bed linen and towels are quite different and so should be washed at different intervals. While every week or two will generally suffice for sheets, towels are best washed every few days.

Anyway, who doesn’t love the feeling of a fresh set of sheets or the smell of a newly laundered towel?

Why you should wash towels more often

When you dry yourself, you deposit thousands of skin cells and millions of microbes onto the towel. And because you use your towel to dry yourself after a shower or bath, your towel is regularly damp.

You also deposit a hefty amount of dead skin, microbes, sweat and oils onto your sheets every night. But unless you’re a prolific night sweater, your bedding doesn’t get wet after a night’s sleep.

Towels are also made of a thicker material than sheets and therefore tend to stay damp for longer.

So what is it about the dampness that causes a problem? Wet towels are a breeding ground for bacteria and moulds. Moulds especially love damp environments. Although mould won’t necessarily be visible (you would need significant growth to be able to see it) this can lead to an unpleasant smell.

As well as odours, exposure to these microbes in your towels and sheets can cause asthma, allergic skin irritations, or other skin infections.

So what’s the ideal frequency?

For bedding, it really depends on factors such as whether you have a bath or shower just before going to bed, or if you fall into bed after a long, sweaty day and have your shower in the morning. You will need to wash your sheets more regularly in the latter case. As a rule of thumb, once a week or every two weeks should be fine.

Towels should ideally be washed more regularly – perhaps every few days – while your facecloth should be cleaned after every use. Because it gets completely wet, it will be wet for a longer time, and retain more skin cells and microbes.

Wash your towels at a high temperature (for example, 65°C) as that will kill many microbes. If you are conscious of saving energy, you can use a lower temperature and add a cup of vinegar to the wash. The vinegar will kill microbes and prevent bad smells from developing.

Clean your washing machine regularly and dry the fold in the rubber after every wash, as this is another place microbes like to grow.

Smelly towels

What if you regularly wash your towels, but they still smell bad? One of the reasons for this pong could be that you’ve left them in the washing machine too long after the wash. Especially if it was a warm wash cycle, the time they’re warm and damp will allow microbes to happily grow. Under lab conditions the number of these bacteria can double every 30 minutes.

It’s important to hang your towel out to dry after use and not to leave towels in the washing machine after the cycle has finished. If possible, hang your towels and bedding out in the sun. That will dry them quickly and thoroughly and will foster that lovely fresh, clean cotton smell. Using a dryer is a good alternative if the weather is bad, but outdoors in the sun is always better if possible.

Also, even if your towel is going to be washed, don’t throw a wet towel into the laundry basket, as the damp, dirty towel will be an ideal place for microbes to breed. By the time you get to doing your washing, the towel and the other laundry around it may have acquired a bad smell. And it can be difficult to get your towels smelling fresh again.

What about ‘self-cleaning’ sheets and towels?

Some companies sell “quick-dry” towels or “self-cleaning” towels and bedding. Quick-dry towels are made from synthetic materials that are weaved in a way to allow them to dry quickly. This would help prevent the growth of microbes and the bad smells that develop when towels are damp for long periods of time.

But the notion of self-cleaning products is more complicated. Most of these products contain nanosilver or copper, antibacterial metals that kill micro-organisms. The antibacterial compounds will stop the growth of bacteria and can be useful to limit smells and reduce the frequency with which you need to clean your sheets and towels.

However, they’re not going to remove dirt like oils, skin flakes and sweat. So as much as I would love the idea of sheets and towels that clean themselves, that’s not exactly what happens.

Also, excessive use of antimicrobials such as nanosilver can lead to microbes becoming resistant to them.

Rietie Venter, Associate professor, Clinical and Health Sciences, University of South Australia

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

When British TV doctor Michael Mosley died last year in Greece after walking in extreme heat, local police said “heat exhaustion” was a contributing factor.

Since than a coroner could not find a definitive cause of death but said this was most likely due to an un-identified medical reason or heat stroke.

Heat exhaustion and heat stroke are two illnesses that relate to heat.

So what’s the difference?

A spectrum of conditions

Heat-related illnesses range from mild to severe. They’re caused by exposure to excessive heat, whether from hot conditions, physical exertion, or both. The most common ones include:

• heat oedema: swelling of the hands, feet and ankles
• heat cramps: painful, involuntary muscle spasms usually after exercise
• heat syncope: fainting due to overheating
• heat exhaustion: when the body loses water due to excessive sweating, leading to a rise in core body temperature (but still under 40°C). Symptoms include lethargy, weakness and dizziness, but there’s no change to consciousness or mental clarity
• heat stroke: a medical emergency when the core body temperature is over 40°C. This can lead to serious problems related to the nervous system, such as confusion, seizures and unconsciousness including coma, leading to death.

As you can see from the diagram below, some symptoms of heat stroke and heat exhaustion overlap. This makes it hard to recognise the difference, even for medical professionals.

How does this happen?

The human body is an incredibly efficient and adaptable machine, equipped with several in-built mechanisms to keep our core temperature at an optimal 37°C.

But in healthy people, regulation of body temperature begins to break down when it’s hotter than about 31°C with 100% humidity (think Darwin or Cairns) or about 38°C with 60% humidity (typical of other parts of Australia in summer).

This is because humid air makes it harder for sweat to evaporate and take heat with it. Without that cooling effect, the body starts to overheat.

Once the core temperature rises above 37°C, heat exhaustion can set in, which can cause intense thirst, weakness, nausea and dizziness.

If the body heat continues to build and the core body temperature rises above 40°C, a much more severe heat stroke could begin. At this point, it’s a life-threatening emergency requiring immediate medical attention.

At this temperature, our proteins start to denature (like an egg on a hotplate) and blood flow to the intestines stops. This makes the gut very leaky, allowing harmful substances such as endotoxins (toxic substances in some bacteria) and pathogens (disease causing microbes) to leak into the bloodstream.

The liver can’t detoxify these fast enough, leading to the whole body becoming inflamed, organs failing, and in the worst-case scenario, death.

Who’s most at risk?

People doing strenuous exercise, especially if they’re not in great shape, are among those at risk of heat exhaustion or heat stroke. Others at risk include those exposed to high temperatures and humidity, particularly when wearing heavy clothing or protective gear.

Outdoor workers such as farmers, firefighters and construction workers are at higher risk too. Certain health conditions, such as diabetes, heart disease, or lung conditions (such as COPD or chronic obstructive pulmonary disease), and people taking blood pressure medications, can also be more vulnerable.

Adults over 65, infants and young children are especially sensitive to heat as they are less able to physically cope with fluctuations in heat and humidity.

How are these conditions managed?

The risk of serious illness or death from heat-related conditions is very low if treatment starts early.

For heat exhaustion, have the individual lie down in a cool, shady area, loosen or remove excess clothing, and cool them by fanning, moistening their skin, or immersing their hands and feet in cold water.

As people with heat exhaustion almost always are dehydrated and have low electrolytes (certain minerals in the blood), they will usually need to drink fluids.

However, emergency hospital care is essential for heat stroke. In hospital, health professionals will focus on stabilising the patient’s:

• airway (ensure no obstructions, for instance, vomit)
• breathing (look for signs of respiratory distress or oxygen deprivation)
• circulation (check pulse, blood pressure and signs of shock).

Meanwhile, they will use rapid-cooling techniques including immersing the whole body in cold water, or applying wet ice packs covering the whole body.

Take home points

Heat-related illnesses, such as heat stroke and heat exhaustion, are serious health conditions that can lead to severe illness, or even death.

With climate change, heat-related illness will become more common and more severe. So recognising the early signs and responding promptly are crucial to prevent serious complications.

Matthew Barton, Senior lecturer, School of Nursing and Midwifery, Griffith University and Michael Todorovic, Associate Professor of Medicine, Bond University

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