Which inner layer suits you? Finding your go-to inner layer before winter arrives

Inner layers may sound simple, but they come in a wide variety of shapes and materials. Cotton is the classic choice, but of course synthetic fibers are also widely available, along with 100% wool and wool-cotton blends—just naming a few shows how many options there are. Shapes vary too: camisoles, tank tops, long-sleeve crew necks, turtlenecks, and more. As the weather starts turning chilly, inner layers—though usually hidden from view—actually play a quietly essential role, supporting warm and comfortable dressing from behind the scenes.

Everyone likely has their own priorities—functionality including warmth and moisture control, the feel against the skin, and even how it looks around the neck and arms when layered under other clothes. In this reading, we'd like to help you find your favorite inner layer as you prepare for the cooler season ahead.

When the seasons change and you're prone to falling out of sorts, that's exactly when you need to adjust with the right inner layer 

Now that October has arrived, autumn finally seems to be settling in—though some days still bring summer-like heat, a true sign of the seasons shifting. While the transition is happening gradually, sudden temperature swings can still put stress on the body. Finding an inner layer that suits you perfectly during this season, when it's easy to feel out of balance, would surely be reassuring. When looking for one, a good place to start is by paying attention to the material.

In this reading, we'll focus specifically on natural materials.

◆ If you're concerned about the temperature difference between day and night, or about feeling cold, choose "wool" 

At ZUTTO, we often introduce wool's excellent year-round functionality, and inner layers are no exception. You may think of wool simply as something that keeps you warm in cold weather, but beyond its insulating properties, its high moisture-regulating ability also keeps you comfortable throughout the year.

◆ If you want a smooth, silky feel against the skin, try "silk blends or yak wool"

Since inner layers touch the skin directly, many people prioritize how they feel to the touch. For those people, even fine, soft wool might feel a bit sensitive. In that case, we recommend silk blends. Silk has long been a rare and precious material used in formal wear like dresses, prized for its smooth, comfortable feel. Even when blended with wool, adding silk gives the fabric a noticeably smoother texture. Inner layers made with yak wool are also wonderfully gentle to the touch, and worth considering.

◆ If you prefer a reliable, classic material, choose "100% cotton"

Among the materials introduced here, cotton is perhaps the one closest to our everyday lives. It's a familiar staple used not only in clothing but also in bags, sneakers, curtains, cushions, and other interior items. Precisely because it's such a classic, cotton comes in many varieties—it's interesting how even the same cotton can give a completely different impression depending on the thread count (thickness).

Now, let's take a closer look at some specific products.

✓For those in the wool camp who prioritize functionality 

First, we'd like to introduce joha, a brand ZUTTO has carried for many years. It has many repeat customers and is a favorite among our staff as well. Since the brand originally started with baby inner wear, it uses delicate merino wool that's both safe and free of the itchy, prickly sensation people often associate with wool.

We spoke with a staff member who actually uses this item.

The item I love is the Merino Wool Tank Top in white.

"I only learned how wonderful wool actually is after starting to work at ZUTTO. I used to picture the scratchy, itchy feeling of sweaters, but when I actually tried it, it lived up to its reputation. Even in summer, trains and indoor spaces often have the air conditioning turned up too high, and I tend to get a chill in my stomach—but wearing joha's wool inner layer means I don't have to worry about that anymore, which makes me really happy."

A shade close to cream. You can really tell how fine the merino wool is—it has such a gentle feel to the touch.

Next, we'd like to introduce the ZUTTO original Cotton Wool Marudo (tube-knit) series. It comes in three shapes: tank top, long-sleeve crew neck, and turtleneck.

This one is a cotton-wool blend with a remarkably smooth feel—so smooth, in fact, that you'd hardly guess it contains wool at all. It was made by Morishita Meriyasu, who blended soft, skin-friendly cotton with wool to create an inner layer suited for three seasons, finishing it using a technique called marudo, in which the fabric is knitted in a seamless tube shape.

Here it's worn as an inner layer under a thin white tank top. Since there's a slight see-through quality, if you choose white, we recommend wearing it as an inner layer. (Model's height: 159cm)

Its stretch and smooth, moist feel against the skin are unlike anything else. Though thin, it's a wool inner layer, so it still offers warmth—making it a perfectly balanced choice. The turtleneck can be worn under shirts or dresses, but it also looks lovely worn on its own, peeking out intentionally.

▼You can also read the behind-the-scenes story. Check out our feature on the original inner layers here.

>>The gentle feel created by extra-fine wool and circular knitting. ZUTTO's original inner wear

✓For those who care about how it feels against the skin—the silk-blend and yak crowd

If you're someone who's particular about the texture of your inner wear, try a silk-blend or yak piece.

Tam Silk, a brand whose very name includes the word "silk." Although it's a Finnish brand, the inner wear we carry has been adjusted to suit Japanese body types, making it a great option for those who find sizing a challenge.

(Model height: 158cm)

This is a long-sleeve T-shirt made of wool-silk fabric, softly knitted on a tsuriami (hanging knitting) machine. It works wonderfully as inner wear, but can also be worn on its own as a cut-and-sew top, which makes it all the more versatile. Compared to joha, introduced earlier, this piece has a relatively relaxed silhouette, so if you're hesitant about clothing that traces the body's lines, this might be the one to try first.

Also, the long-selling joha item mentioned earlier is a wool-silk blend as well. It's no surprise that repeat customers buy it in bulk—the comfort really speaks for itself.

85% merino wool, 15% silk. The body is long, so it also helps guard against chill around the waist.

Available in navy and off-white, with slightly different designs for each.

▼ There's also a comparison article written by a staff member who loves both joha and Tam Silk.

>>Midwinter wool inner wear: a comparison and recommendations from joha and Tam Silk devotees

The yak series from Tenimuhou is also popular.

Great as home wear, or as leggings for going out.

A yak is a relative of cattle that lives in the harsh environment above 3,000 meters in altitude. Yak wool isn't widely known, but its soft down-like fiber is a truly luxurious material, comparable to cashmere. This series is made from a blend of that yak wool with supima cotton, a material unique to Tenimuhou.

A stretchy, easy-to-wear material.

One fiber comes from an animal, the other from a plant. Both are long, very soft, natural fibers with a beautiful sheen. Another feature is that the natural colors of the yak wool and cotton are left as they are, undyed.

✓For those who love the classics—the cotton crowd 

For those who feel most at ease with classic cotton, we have a range of options too. First is ZUTTO's original Supima Irregular Telecom Round-Body Tank Top.

This tank top is made using fabric from Kinan Meriyasu, a long-established fabric mill in Wakayama—Japan's leading production area for circular-knit fabric (cut-and-sew material). The thread used is supima cotton, one of the finest grades of cotton, cultivated through selective breeding to produce an extra-long-staple fiber known as pima cotton.

We also paid close attention to the shape. Around the neck, we aimed for just the right degree of openness—not too wide, not too tight. And around the underarms, an area that can often feel bothersome when worn, the fit is snug and neat.

It pairs nicely with V-neck clothing. (Model height: 159cm)

The fit around the underarms, an area of concern, is also snug. There's no worry about it showing through your clothes, yet it doesn't feel constricting thanks to the stretchy fabric. (Model height: 159cm)

Another ZUTTO original we'd love to recommend is the charmingly named Pancake Cotton series.

The Pancake Cotton Long-Sleeve Turtleneck is great for layering, too—it can really change the impression of an outfit.

This fluffy, smooth cotton fabric, with its soft elasticity, is reminiscent of a beautifully baked, glossy pancake. The fabric feels so lovely against the skin every time you touch it, it's earned the name "pancake knit." It's carefully knitted on old-fashioned, hard-to-handle specialty knitting machines, resulting in a cut-and-sew fabric with a texture unlike your typical knit. Even though it's also 100% cotton, it's quite different from the Supima Irregular Telecom Round-Body Tank Top.

It's also easy to wear on its own as a cut-and-sew top. (Model height: 159cm)

Dress: Camisole Dress, Bangle: LADIES Bangle STUDEBAKER BROAD CUFF 1INCH POLISHED

A staff member who loves this piece says the texture is what she'd recommend most.

"This series is airy and full, with a smooth, almost melting texture that I really love. I also like how gentle it looks on when worn. It has good insulating properties too, so I'm looking forward to relying on it as inner wear in the coming season."

Bonus: making smart use of targeted pieces.

Having items on hand that warm specific parts of the body lets you stay comfortable just by adding them to the inner wear you already own. Here we introduce the socks and belly warmers from the Tenimuhou yak series mentioned earlier. 

The stomach is an area that tends to get cold easily. Since it's made slightly thinner so as not to interfere with the clothes worn over it, the waist won't feel tight even with pants styles. It's useful not just in the chillier season but year-round, including as a countermeasure against summer air conditioning. For those also worried about cold feet, we also recommend the socks.

Perhaps the simplest way to describe how useful this item is would be to call it a sock with a built-in leg warmer. Wearing it loosely gives your legs a bit of volume, which pairs nicely with boots or sabots. The opening also has a loose elastic design, so it doesn't dig in—a welcome point, since it leaves less of a mark on your skin.

It also pairs well as an addition to your room wear.

Slippers: Comfort Shoes 7281-RUB-W CHARCOAL GREY

Innerwear is something you choose differently depending on its purpose and the clothes you're pairing it with. Of course, rather than settling on just one, if you can gather items in a few different materials and choose according to the weather and outfit of the moment, we think even your everyday clothes will feel more comfortable to wear. As this is also an item that makes for a welcome gift in the season ahead, please take your time choosing the one that suits you best.

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