Underdays Launches UNDERskin™ Underwear Infused with Skincare Technology
Discover Underdays’ new UNDERskin™ underwear featuring skincare-infused fabric with prebiotics and probiotics for everyday intimate skin care and comfort
New Delhi: Underdays has introduced UNDERskin™, a new underwear collection that combines skincare with everyday comfort. Instead of simply covering your skin, these undergarments are designed to support your intimate skin throughout the day using fabric infused with synbiotic technology.
As skincare routines become more advanced, people often focus on products for their face and body but overlook the skin that remains covered by underwear for most of the day. UNDERskin™ aims to change that by turning underwear into an active part of a daily self-care routine.
How Underdays Was Founded: The Story Behind the Brand Redefining Everyday Underwear
Underdays was founded in December 2021 by Amelie Salas and Oria Mackenzie, who met while working in brand marketing and partnerships at luxury fashion platform Farfetch.
Oria spent several years at Farfetch and saw the company grow from a startup into a global business. Amelie joined the company in 2018 after gaining experience at Burberry, bringing her expertise in fashion and branding.
The idea for Underdays came after the two attended an underwear sample sale following work. While shopping, they realised there were very few options that combined comfort, style, and practicality. Most products were either uncomfortable lace designs or plain basics that did not meet the needs of modern women.
They believed the underwear industry had not evolved in the same way as the beauty and wellness industries, where brands had become more innovative and focused on consumers’ everyday needs.
During the COVID-19 pandemic, the founders spent months researching the market, speaking with women, conducting surveys, and developing product prototypes to understand what customers really wanted from their underwear.
They initially funded the business themselves with support from family and friends. They also worked with a lingerie graduate from the London College of Fashion to develop the products while building the brand identity and supply chain from the ground up.
The result was Underdays, a brand focused on creating comfortable, inclusive, and responsibly made underwear. The company offers sizes from XS to XXL and aims to combine comfort, health, and style in products designed for everyday wear.
Through Underdays, Salas and Mackenzie hope to change the way women think about underwear by turning it from a basic necessity into an important part of everyday self-care and confidence.
Why Intimate Skin Needs Extra Care
The skin around the intimate area is much more delicate than other parts of the body. Experts say it is up to 10 times more permeable, making it more sensitive to heat, moisture, friction, and certain fabrics.
Since most people wear underwear for 12 to 16 hours every day, the type of fabric they choose can affect skin comfort. Some synthetic materials may trap heat and moisture, which can contribute to irritation, dryness, discomfort, and an imbalance in the skin’s natural environment.
Underdays developed UNDERskin™ to help support intimate skin instead of simply covering it.
What Is UNDERskin™ Technology?
UNDERskin™ uses HeiQ Skin Care™, a Swiss-developed synbiotic technology that is woven directly into the fabric.
The underwear is made from:
92% TENCEL™ Micromodal, a soft fibre derived from trees
8% elastane for stretch and flexibility
The fabric contains both:
Prebiotics, which help nourish beneficial bacteria already present on the skin
Probiotics (Bacillus strains), which introduce beneficial microbes to support a healthy skin microbiome
These ingredients are held inside a 100% bio-based slow-release system. Body heat and normal movement gradually release the active ingredients onto the skin during daily wear.
Unlike creams or lotions, there are no additional skincare steps. Simply wearing the underwear allows the technology to work throughout the day.
According to the company, the skincare benefits remain effective for up to 40 gentle washes at 30°C.
How Does It Benefit the Skin?
The goal of UNDERskin™ is to support healthier-looking intimate skin by helping maintain the skin’s natural microbiome.
According to Underdays, the technology may help improve:
- Skin softness
- Smoothness
- Hydration
- Overall skin appearance
- Skin barrier function
The product is designed as a cosmetic textile rather than a medical treatment. It does not claim to prevent or treat infections or medical conditions.
Instead, it focuses on supporting everyday skin health and comfort.
Why the Skin Microbiome Matters
The skin microbiome is made up of beneficial microorganisms that naturally live on the skin.
A healthy microbiome helps:
Protect the skin barrier
Maintain hydration
Reduce irritation
Support healthy-looking skin
When this balance is disturbed by sweat, friction, hormones, stress, or synthetic fabrics, people may experience discomfort, dryness, odour, or irritation.
Synbiotic technology combines prebiotics and probiotics to help support this natural balance.
Studies on microbiome-focused skincare suggest that maintaining a healthy microbiome may improve skin smoothness, reduce redness, and improve overall skin quality.
Research on functional textiles has also found that fabrics containing active ingredients can help improve hydration, reduce water loss through the skin, and support better skin comfort.
Some antimicrobial and specialised intimate fabrics have also shown benefits in reducing irritation and improving comfort for people with certain skin concerns.
While large independent clinical studies specifically on UNDERskin™ are still limited, the technology is based on existing research involving microbiome skincare and functional textiles.
Comfort Remains a Priority
Although the underwear contains skincare technology, Underdays says it still feels like its regular Everyday collection.
The fabric is designed to be:
Soft and breathable
Lightweight
Comfortable for all-day wear
Invisible under clothing
The collection includes several styles, including:
Thongs
Briefs
Cheeky styles
High-waisted underwear
Customers can choose from colours such as Black, Lilac, Sand, Butter, and Taupe.
The underwear also includes extended antimicrobial gussets for added freshness throughout the day.
Sizes range from XS to XXL.
A Growing Trend in Wearable Skincare
UNDERskin™ is part of a growing trend known as wearable skincare, where clothing is designed to provide benefits beyond comfort.
Researchers have explored fabrics that contain:
Moisturising ingredients
Antimicrobial technology
Cooling materials
Circulation-supporting fibres
Microbiome-supporting ingredients
Instead of relying only on creams and skincare products, wearable textiles aim to provide continuous support while people go about their daily activities.
UNDERskin™ applies this concept specifically to intimate wear.
Caring for the Underwear
To maintain the skincare technology, Underdays recommends:
Washing on a gentle cycle
Using water at around 30°C
Air drying the garments
Washing similar colours together
Following these care instructions helps preserve the active ingredients for up to 40 washes.
Is It a Replacement for Skincare?
UNDERskin™ is designed to complement an existing skincare routine rather than replace it.
People can continue using their preferred skincare products while benefiting from the added support provided by the fabric.
The underwear is intended to offer continuous care during everyday activities, making skincare more effortless.
How to Buy Underdays UNDERskin™ Underwear and Is It Available in India?
You can buy UNDERskin™ underwear directly from the official Underdays websites: theunderdays.com (UK) and us.theunderdays.com (US). The websites offer the complete UNDERskin™ Everyday collection, along with starter kits, underwear sets, and accessories such as the Scuba Cloud Pouch.
The company provides a simple checkout process with flexible payment options like Klarna in supported regions. Shoppers can also take advantage of regular offers, including discounts on multiple purchases. Detailed size guides are available to help customers choose the right fit.
Underdays usually processes orders within one to three business days. Customers can choose between standard and express shipping, depending on their location.
Can You Buy Underdays UNDERskin™ in India?
Underdays does not currently list India as one of its main shipping destinations. The brand mainly serves customers in the United Kingdom, the United States, Australia, and selected European countries.
However, customers in India may still be able to place an order through the UK website if international shipping is available for their location. International orders may be subject to customs duties, taxes, and import charges, which are either calculated during checkout or collected when the package arrives.
Delivery to India generally takes 7 to 14 days or longer, depending on the shipping carrier and customs clearance.
Some Indian customers may also choose to use a package forwarding or reshipping service, which provides a delivery address in countries where Underdays ships before forwarding the package to India.
Returns and Exchanges
Underdays accepts returns for eligible UK and US orders within 30 days, although hygiene rules apply to intimate apparel. Return policies for international orders may differ, so customers should check the company’s terms before placing an order.
Because popular colours and sizes can sell out quickly, shoppers may find it helpful to purchase new collections soon after they are released. The company is also expected to expand its availability to more
The Future of Intimate Wellness
As interest in microbiome-based skincare continues to grow, wearable wellness products are becoming more common.
UNDERskin™ shows how everyday clothing can evolve beyond comfort and style by incorporating technologies designed to support skin health.
Although more independent research will help strengthen the evidence in the future, this innovation highlights a new direction for intimate self-care.
For people looking for comfortable underwear that also supports skin wellness, UNDERskin™ offers a practical combination of fashion, comfort, and skincare in a single product.
