Is It Better to Shower in the Morning or at Night?

The question has prompted debate for years: is it best to shower in the morning or at night?

Those who favour a morning shower often see it as the clear choice, saying it wakes you up and leaves you feeling fresh for the day ahead. People devoted to a night shower, meanwhile, may say it is preferable to "wash the day away" and unwind before going to bed.

So, what does the evidence really show? As a microbiologist, I can say there is, in fact, a clear answer.

To begin with, it is worth emphasising that showering forms an essential part of a sound hygiene routine, whenever you choose to do it. A shower removes dirt and oil from the skin, helping to reduce the risk of skin rashes and infections.

It also washes away sweat, which can reduce body odour.

Although sweat is commonly blamed for body odour, it is actually bacteria living on the skin's surface that create it. Newly produced sweat is odourless.

However, skin bacteria - particularly staphylococci - use sweat as a nutrient source. As they break it down, they release sulphur-containing compounds known as thioalcohols, which produce the familiar pungent BO smell.

Morning or night shower?

Over the course of the day, your body and hair unavoidably gather pollutants and allergens, including dust and pollen, as well as sweat and sebaceous oil. Some of these particles remain on your clothes, but others will inevitably make their way onto your sheets and pillowcases.

Sweat and oil on the skin also encourage the growth of bacteria that make up your skin microbiome. These microbes can likewise be transferred from your body to your bedding.

A night shower can remove some of the allergens, sweat and oil accumulated during the day, meaning less of it reaches your bed linen.

Yet, even after showering immediately before bed, you will still sweat overnight, whatever the temperature. Skin microbes will feed on the nutrients in that sweat. By morning, this means you will have deposited microbes on your sheets and will probably wake up with some BO too.

The cleansing advantages of a night shower are especially undermined if bedding is not washed regularly. Odour-causing microbes in the sheets can transfer onto your freshly cleaned body while you sleep.

A night shower also cannot prevent skin cells from being shed. These cells may become food for house dust mites, whose waste can trigger allergies.

Without regular washing of your sheets, deposits of dead skin cells can build up, feeding increasing numbers of dust mites. Their droppings may cause allergies and worsen asthma.

Why a morning shower may be better

By contrast, morning showers can wash off dead skin cells, along with any sweat or bacteria acquired from your sheets during the night. This matters particularly if your bedding was not freshly laundered before you went to sleep.

Taking a morning shower means your body is likely to be cleaner of skin microbes picked up overnight when you put on clean clothes. You also begin the day with less sweat for odour-producing bacteria to consume, which will probably help you stay fresher-smelling for longer than someone who showered at night.

As a microbiologist, I support showering during the day.

Naturally, shower preferences differ from person to person. Whichever time you choose, how effective your shower is will depend on several aspects of your personal hygiene routine, including how often you wash your bed linen.

Wash your bed linen regularly

Whether you favour a morning or evening shower, regularly cleaning your bed linen is essential. Sheets and pillowcases should be laundered at least once a week to remove accumulated sweat, bacteria, dead skin cells and sebaceous oils.

Washing also gets rid of fungal spores that may be growing in the bed linen, along with the nutrient sources that these odour-producing microbes need in order to grow.

Primrose Freestone, Senior Lecturer in Clinical Microbiology, University of Leicester

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