The trendy underwear women should avoid. And the type they should try

It’s one of our most worn items of clothing, and yet we often pay little attention to the particulars of the underwear we buy. At most, we consider what’s most comfortable and durable – whatever will do the job and last the distance.

But like all clothing, and perhaps even more crucial for women, the fabrication of the underwear we go for matters.

In recent years, there’s been an increase in underwear brands that market seamless pieces made with “bamboo” as a better, more eco-friendly option by virtue of it being natural and due to bamboo’s capacity to grow quickly without intervention and absorb carbon dioxide.

The reality is a little more complicated.

“Bamboo can be pretty problematic,” says Dr Dylan Hegh, Future Fibres Facility manager at the Deakin University Institute for Frontier Materials.

There are two main ways that bamboo can be used in clothing. The first is without chemical processing, which is rare and not commonly used in women’s underwear.

The second is where the bamboo is ground to a pulp and used as feedstock to make a semi-synthetic fibre via a technique called wet-spinning. The resulting textile is called viscose. “Viscose is rather problematic as it uses harmful polluting industrial chemicals in its creation – this is what is typically meant by ‘bamboo fibre’,” explains Hegh. “There is a fair bit of greenwashing involved.

“The conceit that bamboo fibre is antimicrobial is largely marketing. The bamboo is antimicrobial but once processed, the viscose loses this property.”

The challenge is the assumption that the valuable properties of the bamboo are transferred over to the viscose, especially that microbial part, says Associate Professor Chris Hurren, director of the ARC Research Hub for Future Fibres.

“But it is very tenuous to exceedingly doubtful. Most evidence shows that doesn’t happen.”

Tencel and Lyocell may also be bamboo-based textiles, made from different chemistry than viscose but use the same wet-spinning technology. “They’re greener but less common than viscose,” Hegh notes.

There’s also the environmental impact of producing bamboo viscose. “It uses chemicals like sulfuric acid and a solvent called carbon disulfide, which is banned in many areas for large industrial uses,” he explains.

Instead, an ideal material for underwear is merino wool because it’s excellent for temperature-regulation, is odour-resistant and moisture-wicking. “There’s been a lot of work done on wool underwear, there’s some science out there that shows the health benefits of wool underwear next to the skin,” says Hurren.

“It’s got really, really high wicking capabilities compared to your synthetic fibres. It’s able to hold that moisture and take it up when you’ve got an excess and then slowly let it out when you’re not as hot and sweaty. This doesn’t happen as well with cotton and viscose.”

Due to the cost of production, however, wool underwear is typically more expensive.

Cotton is another great affordable option, and one that’s recommended by vulva clinics, says Professor Julie Quinlivan, adjunct clinical professor at the University of Notre Dame Australia Institute for Health Research. “It’s hypoallergenic cloth and so is associated with a lower risk of vulvo-vaginal issues at all stages of life compared to synthetic cloth such as nylon,” Quinlivan says.

“All underwear should be washed in low-allergic detergent and is ideally double rinsed in women with vulvo-vaginal pathology,” she says, referring to the broad spectrum of conditions affecting the vulva and vagina.

Cotton is also excellent for moisture management, though it’s not necessary to go for 100 per cent cotton options. It’s important to consider the material combinations when weighing up what will be the best value for money, Hurren says.

“If you’ve got a cotton-polyester underwear that’s poorly made, where the cotton falls out, and you throw the underwear out after 10 or 20 uses, versus a nylon underwear that you get 200 or 400 uses out of, that might be better for the environment,” he says.

In instances where you want to go for something a little more luxurious, silk is safe and naturally hypoallergenic.

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