It is not the fundamental historical dilemma of "to be or not to be", but it is one that is constantly on our minds: Is it better to bathe in the morning or before going to bed at night? Exploring this choice brings us important revelations.

Proponents of doing it in the morning argue that showering, cold or lukewarm, helps wake up the body, and makes you feel fresh and ready to start the day.

While those who bathe at night, before going to bed, express that it helps them eliminate the dirt of the day before getting under the sheets and succumbing to a restful sleep.

Of course, there are also those who don't give themselves a hard time by subjecting themselves to a choice, but rather shower two or even three times a day, and even those who don't do it daily.

But what does science say about which of the two options is really more beneficial?

Impact on health

Bathing performs the essential task of helping to remove dirt, oil, and sweat from the skin. All of these accumulate throughout the day, along with pollutants, dust, and pollen from the environment, which is why nightly cleansing is important, as otherwise, residues settle on your sheets and pillowcase. Plus, your skin is teeming with microbial life.

If you zoom in on any square inch of skin, you'll find between 10,000 and one million bacteria living there. They feed on the oil secreted by your sweat glands, recalls the BBC Future health section.

Added to this is that, although sweat itself doesn't smell, the sulfur compounds produced by bacteria like staphylococcus do; Showering before bed may therefore seem like the most hygienic option. However, this isn’t always the case, and there is no consensus on this. There are nuances, and what Holly Wilkinson, senior lecturer in Wound Healing and the Microbiome at the University of Hull, UK, says: “Probably,It may be more important to wash your sheets than to shower at night (…) because if you shower and leave the sheets on for a month, they will accumulate bacteria, dirt, and dust mites.” The conclusion is that it means the same as not bathing at night.

He argues that this is a problem, since prolonged exposure to dust mite excretions increases the risk of allergies.

Furthermore, if you are sensitive to allergens such as pollen, not washing your bedding is also likely to worsen your symptoms. Even regularly going to bed with dirty sheets increases the possible risk of skin infections.

Sleep Quality

Advocates of nighttime showers argue that they help them sleep better, and there is evidence to support this.

For example, a meta-analysis comparing the results of 13 studies found that taking a 10-minute warm shower or bath once or twice hours before bedtime significantly shortened the time it took to fall asleep, reports the BBC.

It is suggested that raising body temperature before cooling it may act as a circadian signal to the body to prepare for sleep.

Yes, but no

Since not everything is absolute, some people are in favor of the morning bath.

Primrose Freestone, a microbiologist at the University of Leicester (UK), prefers to shower in the morning, as this will remove much of the sweat and microbes accumulated overnight in bed, allowing you to start the day fresher and cleaner.

On the other hand, "if you shower at night, you go to bed clean and refreshed, but you will continue to sweat throughout the night," sometimes for up to eight hours.

According to Freestone, even in cold climates, a person continues to sweat up to half a liter of sweat in bed and deposits 50,000 or more skin cells, a breeding ground for dust mites.

“You’re still going to create a sweaty microenvironment that the bacteria on your skin absorb, producing a slight body odor. So, when you wake up in the morning after a shower at night, you’ll still smell a little,” she says.

Cold or Hot Shower?

Shower water temperature significantly affects physical and mental health, with varying effects depending on whether it’s cold, warm, or hot.

Cold showers improve blood circulation by vasoconstriction and vasodilation, strengthening the immune system and reducing muscle inflammation, which speeds physical recovery after exercise. In addition, the shock of cold water stimulates the release of norepinephrine and endorphins, neurotransmitters that improve mood, reduce stress and anxiety,and increase mental alertness and attention span. Cold water also increases oxygenation of the body by speeding up breathing and heart rate.

Bathing in hot water relaxes tense muscles and calms the mind, making it recommended for relieving tension and promoting deep, restful sleep. Steam helps open airways, which is beneficial for colds or allergies. However, hot water can dry out the skin by removing its natural oils and can worsen conditions such as varicose veins or edema due to its vasodilatory effect.

Meanwhile, warm water offers a balance, being warm enough to relax without causing irritation or dryness, ideal for people with sensitive skin or conditions such as eczema.

Day or night?

Ultimately, your decision is likely to have little influence on your health; It’s more a question of whether you prefer to be fresh and clean during the day or at night.

Conflicting opinions from microbiologists and health experts rather open the gap.

“If you shower once a day, it probably doesn’t matter what time you do it,” says Wilkinson.

She leaves a note to consider: “It depends on the type of work you do; for example, if you’re a farmer, you’ll probably want to wash when you get home at the end of the day, but I think keeping your bed clean is more important.”

So as long as you wash key areas daily, showering or bathing twice a week is probably enough to maintain health and hygiene.