Jumping in the shower is meant to leave us feeling fresh, clean and invigorated.
Many of us spend hours a week scrubbing, buffing and enjoying a hot shower to invigorate us in the morning or send us off to sleep at night.
But startling new research reveals the spray that comes out of a unit could be more dangerous and dirtier than the water in our loo.
Scientists at Manchester University studied the slime that builds up inside showers on behalf of shower disinfectant system Shower Klenz.
Their research into bathroom scum found bacteria and fungi linked to a range of illnesses from Legionnaires' and Crohn’s disease to septicaemia and skin, hair, ear and eye complaints.
And in some cases, these risky illnesses can kill.
Dr Paul McDermott, a former Health and Safety Executive Inspector and an expert in Legionella risk control, has been monitoring the findings.
Read more:Woman shed whole body's worth of skin four times every day due to severe condition
He said: “Nobody wants to stand under a shower knowing the water coming out of it is dirty.
"But water from an untreated shower could contain more bacteria than you’d find in your toilet.
“The aerosols created when you’re stood under the spray can send any bacteria from the water system into your lungs, onto your body and, in certain circumstances, into the bloodstream too.”
Read more:The 10 health problems and niggles that you really shouldn't ignore
Here, we look at how the bugs lurking in your bathroom can harm your health.
Dirty shower water in the eyes can lead to an infection called keratitis or inflammation of the cornea which is linked to the Malassezia fungi.
Ophthalmologist Alexander Ionides of Clinic Compare says people who shower in contact lenses are the most at risk because they can suffer from minor scratches to the cornea - making them more susceptible to infection.
Bacteria called Acanthamoeba could get into the eyes and cause horrific eye infections and could even lead to blindness.
He explained: “All water sources such as baths, showers, bathroom sinks, pools and sea water, contain the free living protozoan Acanthamoeba, which can cause this painful eye infection that can lead to blindness.
“This can be treated by antibiotic and antiseptic drops but the treatment can last for many months and even years - sometimes the treatment can involve a corneal graft in severe cases.
“Contact lenses do naturally cause minor scratches on the cornea which make it more susceptible to bacterial infection.
"However the Acanthamoeba is especially attracted to the contact lens and any natural bacteria living on the cornea can serve as a food source for the Acanthamoeba, enabling it to survive.
“It's always best to remove your lenses before coming into contact with any type of water source.”
Scientists also found a bacterium called Pseudomonas aeruginosa which causes eye and ear infections.
This can lead to a condition called ‘swimmer’s ear’ and symptoms include swelling, pain, itching, difficulty hearing and discharge from the ear.
It is a tough bacteria which is hard to be rid of, but it doesn't generally affect healthy people and normally only strikes when someone is unwell or run down.
If it infects lung tissue, for example in a cystic fibrosis patient, it can cause a form of pneumonia whereas if it entered a cut or burn it could lead to extensive tissue damage or even septic shock.
Dr McDermott said: “Pseudomonas aeruginosa can affect the ears and eyes.
“For healthy people who may pick up an infection from a shower or swimming pool, they can generally get over it, but for certain patients receiving treatment in hospitals, infection can be much more serious, and even life-threatening.”
People catch Legionnaires’ disease when airborne droplets carrying the Legionella bacteria are inhaled into the lungs.
Legionella bacteria thrive in warm water between 20-45C, with temperatures of between 35-37C being the optimum - perfect for those who like their showers hot.
Symptoms can be flu-like at the start; tiredness, a cough, headache, high temperature or chills and fever and can be it is often misdiagnosed.
But if not treated quickly, it can be fatal - particularly in patients whose immune system has already been weakened such as the elderly, people with underlying respiratory problems or who are recovering from illness or surgery.
Smokers are also at greater risk of contracting the disease.
Dr Paul McDermott explained: “The mortality rate for Legionnaires’ disease is around 12% but when people contract the disease in hospital it rises to about 30% - more than double what it would be in the community outside.
“That is because many hospital patients are already immunocompromised.
"Legionnaires’ disease can affect anybody so, if you have symptoms and are concerned, go to your GP or hospital.
“There is a very simple test that can give a diagnosis within an hour. The key is that people do ask for that test if they are genuinely concerned that they have the disease.
"Legionnairres’ can be treated with antibiotics if administered early enough but without treatment it can kill.”
Out of the 922 cases of Legionnaires’ disease in England and Wales between 2012 and 2014, 89 were fatal.
The Manchester University research also identified a fungi called Malassezia restricta that lives inside the black gunge in our shower heads. This causes dandruff and infections on the scalp.
Professor Mat Upton, who led the team, said that the fungus in the shower heads are 'of concern' - especially for those conscious about having a flaky scalp.
He said: “On the basis of the preliminary findings we have made, the fungal organisms may be of more concern.
“The organisms found included those that have been linked to skin infections and dandruff.”
A previous study by experts at L’Oreal haircare found the higher the concentration of Malassezia restricta on the scalp, the more likely the person was to suffer dandruff.
But it's not just a flaky scalp you have to watch out for - you could be at risk from a nastier infection found in and around the head.
Folliculitis, where spots, rashes and patches of itchy skin form around hair follicles, can also come from germs in the shower head.
Dr Stefanie Williams, Dermatologist and Medical Director at European Dermatology London, explained: “Tap water coming from shower heads have been shown in studies to harbour various microbes such as bacteria and fungi that cause skin infections.”
A study by Lancaster University found one in ten shower heads were contaminated with a pathogen called Mycobacterium avium subspecies paratuberculosis.
The complex-sounding bacteria has worrying consequences - it has been linked to Crohn's disease, a long-term illness that can have serious effects on sufferers.
Crohn’s disease is a condition that affects the digestive system and causes nausea, weight loss, diarrhoea and tiredness.
Experts suggest running the shower for a short period before stepping into it which can reduce the chance of coming into contact with the pathogen.
Professor Roger Pickup from the university's faculty of Health and Medicine said: “We have found Mycobacterium avium subspecies paratuberculosis in showers for the first time.
“It comes through the water system and with the other bacteria forms a biofilm in the shower tube and then this grows and gets washed off and comes through in the shower water.
“We recommend that in line with precautions against Legionnaires’ disease, showers should be run for a short period before use - particularly those that have not been used for a while.”
There is no cure for Crohn’s disease but many sufferers find changes to their diet can ease the symptoms. Around 250,000 people in the UK suffer with the condition.
Researchers at the Sant’ Antonio Abate Hospital in Naples in Italy found that contaminated shower water can cause skin infections after operations or beauty treatments.
Women who had recently had a leg wax were highlighted as a group at the most risk as hair follicles were open and more vulnerable to infection.
They concluded: “Based on our experience, we suggest that shower or bath exposure should be included amongst the possible pathogenic events causing folliculitis.”
Dr Stefanie Williams agreed, saying that people who have had Microdermabrasion or laser treatment should consider washing with sterile, bottled water.
This is because procedures take away dry, dead skin and the new, smoother layer of skin underneath can be sensitive.
She said: “I don’t think we need to worry. But, an exception with regards to simple shower water might be post-operative or post-procedure skin, where the skin integrity is impaired and germs have an easier ‘way in’.
“For example, after an ablative CO2 laser treatment of the face, I might recommend not using tap or shower water, but purchased sterile water to wash with for the first few days after the procedure, in order avoid secondary infection.”
Read moreHow to get younger looking skin Best face cleansing tools Best spot creams to combat acne Best night creams
A worrying germ named Pseudomonas aeruginosa can be found in biofilm - the bacteria that collects on shower heads and in baths - and if these culminate in infections in the blood, they can be fatal.
Dr Paul McDermott said this was a particular worry with patients who are already very poorly and in hospital.
This is because their weak immune systems aren't able to fight it - and it could bring on the septicaemia.
He explained: “Pseudomonas are opportunist pathogens and those most at risk of infection are people who aren’t well and whose immune systems sadly don’t have the ability to fight it.
“It can lead the blood being infected which can cause septicaemia. Pseudomonas aeruginosa is resistant to many antibiotics too, so treatment can be very difficult.
“Infections by Pseudomonas are common in hospitals and unfortunately deaths through septicaemia can be a result of these.”