You might think you’re being generous to others, or kinder to the planet by sharing certain items rather than using your own. In fact, you could be exposing yourself to a whole host of potential illnesses. These are the items experts say you should keep to yourself to avoid catching disease and potentially passing on infections…
Towels: Grabbing the nearest towel in the bathroom, despite it not being yours, might seem like the easiest option, but research by microbiologists at the University of Arizona found that 90% of bathroom towels are contaminated with faecal bacteria and 14% of them carry E.coli.
Make sure it’s clear which towel belongs to which person in your bathroom and aim to wash all of them after every three to five uses.
Toothbrushes: According to Doctor Brendan Khong, sharing a toothbrush is an absolute no-go. “If sharing a toothbrush, you’re more likely to pick up a common cold and/ or flu caused by rhinovirus or the influenza virus, while streptococcus bacteria can cause strep throat and sore throats,” says Dr Khong.
“Hepatitis B and C are blood borne viruses and can transmit from one to another if there is bleeding or cuts in the mouth. Human Papillomavirus (HPV) can lead to warts and increase the risk of oral cancers and fungal infections such as oral thrush are caused by fungi called candida.”
He adds: “Forgotten to bring your toothbrush for a sleepover? Use mouthwash, a clean cloth and water or chew gum which can stimulate saliva production.”
However, if the mouthwash doesn’t belong to you, don’t take it from the lid. Instead pour the amount you want into a cup and take it from there to save catching germs that way.
Razors: Make sure you and your partner or flatmate have different razors in the bathroom, as sharing the same one could lead to problems. “We are taking off some of the top layers of dead skin cells and bacteria when we use our razor. This then sits on the razor which moves onto someone else’s skin when they use it,” says GP Dr Aarthi Sinha.
“This can lead to minor infections like cellulitis or impetigo, which if untreated – or in people with pre-existing skin conditions or immune problems – can lead to spreading infection, making them unwell.”
There is also a risk of passing on or catching blood-borne viruses such as HIV if you nick yourself while shaving.
Mascara: Think again before lending your mascara to a friend. A study conducted on mascaras found microbial growth in 36.4% of the tubes that were tested. “There are bugs that sit on our eyelids and around the lashes, which usually get deposited in the mascara bottle and can be transmitted into the eyes of someone else who shares that. This often causes conjunctivitis, which presents as red, sticky eyes,” says Dr Sinha.
If you really want to share make-up, have your own personal applicator and avoid ‘double dipping’ these into the mascara tube.
Water bottles: If you’re drinking directly from someone else’s water bottle, you’re likely to pick up or pass on lingering germs. Research has found that 73% of people in a 2024 study drank straight from their water bottles and 50% shared their water bottles with others.
“Bugs and bacteria from our mouths get deposited on the water bottle and potentially in the water itself,” says Dr Sinha. “These may be natural for our genetic make-up but not for someone else, who could get a stomach upset. There is also the risk of passing on cold sores, colds and flu, and covid too.”
According to the same study, microbial load on polyethylene terephthalate (PET) is relatively high when compared to stainless steel, so you may want to opt for a metal bottle rather than a plastic one.