The frontrunner to be prime minister has been spotted seemingly wearing the same pair for more than one day. It may be environmentally friendly – but is it hygienic?

In the run-up to the Conservative leadership election, the frontrunner, Boris Johnson, has been dogged by a fresh scandal: claims that he hasn’t washed his socks. The pair in question are thought to be emblazoned with the image of King Ashurbanipal, ruler of the Neo-Assyrian empire from 668 to 627BC, and available for £5.99 from the British Museum. He was spotted wearing them at the first hustings in Birmingham on Saturday, then again on Monday for a chat with the BBC’s Laura Kuenssberg. The socks saw a third outing during the leadership contender’s interview with TalkRadio’s Ross Kempsell on Wednesday.

Johnson’s team said he owns “multiple pairs of similar patterned socks” and wears a clean pair each day. Of course, it is possible that Johnson owns several pairs of the same socks but, after images emerged of his less-than-pristine car interior last week, it is easy to see why commentators suspect he could be recycling the same pair. But is it unhygienic to wear socks more than once without washing them? And how often should the rest of your wardrobe be given a good clean? We asked the cleaning expert Aggie MacKenzie for her verdict.

Socks

“I think it’s OK for kids not to wash their socks between wears, but grown men should – it’s only polite,” says MacKenzie. The type of work you do or the shoes you wear are irrelevant, she adds. “I think you should change them every day without question.”

Facebook Twitter Pinterest The same socks seemingly made a second appearance in a BBC interview. Photograph: BBC news

Bras

“I used to copresent a show called Too Posh to Wash, and one woman we interviewed hadn’t washed her bra for about eight years,” says MacKenzie. “But I think maybe don’t leave it quite as long as that. Wearing the same bra day in, day out is not going to make you ill … it’s just the notion of it. It will be crawling with bacteria, that’s for sure, but it’s your own bacteria – it’s not going to do you any harm. I think washing a bra every couple of days is fine.”

Pants

“This one’s a no-brainer! Wash them every day,” says MacKenzie. But what about in an emergency? “If you know you are going to have to go two days, put a layer of loo paper or something in between, or run a makeup remover wipe along the bottom. Depending on your personal preference, you could just go without. If you have tight-fitting jeans with lots of ridges, it may not be a good idea … or, actually, that could be quite pleasant.”

Jeans

“Manufacturers say you should more or less never wash their jeans, but I would disagree,” says MacKenzie. “I like to wash my jeans as soon as they start to feel a bit loose.” Increasingly, we are being encouraged to wash our clothes less frequently in order to lighten the load on the environment, and jeans are one of the best items to wash less often, she says. “Also children’s clothes – you don’t need to wash those every day, just given them a quick wipe down with a damp cloth if they have spilled food on them.”

Coats

“I take coats to the dry cleaners because you will usually upset the structure of a coat if you put it in a washing machine,” says MacKenzie. “But don’t go mad and don’t waste your money: just wait until it looks dirty and becomes slightly embarrassing.” Johnson, take note.