Bamboo viscose versus fleece

Short answer: Fleece warms the most at the lowest weight, but it is made of plastic and smells quickly. Bamboo viscose is softer against the skin and better as the first layer.

What fleece is actually made from

Fleece is polyester with a brushed surface that holds air between the fibers, and it is this trapped air that actually warms the body. This is why fleece is light and warm to wear, but it does not move moisture away from the skin as effectively as a cellulose fiber like bamboo viscose does daily.

The two belong to different layers of clothing

Fleece typically belongs as a second or third layer, meaning worn over a thinner layer that sits closer to the body underneath. Bamboo viscose instead belongs as the first layer against the skin, where softness and moisture absorption matter most for comfort. Used together in this order, you get both warmth and dryness. See bamboo undershirt for men.

Odor and static electricity in winter

Fleece smells relatively quickly because oils from the skin get trapped in the brushed fibers, and it also becomes easily static in dry winter weather outdoors. Bamboo viscose has neither of these issues to the same extent, no odor and no static electricity causing uncomfortable little shocks. See sweatwear if you want a softer alternative on the outside.

Pilling and how the fabric ages

Fleece pills over time and goes flat where it rubs against bags, straps or other clothing during everyday activities and movement. It then warms less effectively, once the air layer between the fibers has been compressed and flattened out. Bamboo viscose changes less on the surface itself, but can wear faster at the seams with very frequent use and washing.

Can you wear fleece directly against skin

Yes, you can, but many find it turns clammy after a short time of activity, especially if you sweat a little while moving around. A thin layer of bamboo viscose between fleece and skin usually solves the problem effectively, because bamboo absorbs the moisture while fleece keeps holding warmth outside that thin inner layer close to the body.

Microplastics from fleece in the wash

Fleece releases microplastics in every single wash, and this is actually one of the largest sources of microplastics among ordinary clothing in an average household. Bamboo viscose is cellulose and therefore does not release plastic fibers the same way during washing. If you think about the environmental impact of your wardrobe, this is worth keeping in mind at your next purchase.

Warmth compared at the same weight

Fleece is markedly warmer than bamboo viscose at the same fabric weight, because the air layer between the brushed fibers insulates effectively against cold outdoors. Bamboo viscose does not warm anywhere near as much and is therefore a poor choice as a sole outer layer in cold weather, where fleece or a jacket is needed instead.

Price and availability in stores

Fleece is generally cheap to produce and is therefore found in many price ranges and qualities in most clothing stores throughout the year for customers. Bamboo viscose typically sits a bit higher in price, but also uses less fabric per garment. See bamboo hoodie for men as a softer alternative to a fleece pullover.

How to choose correctly for winter

If you need a warm outer layer that insulates well, fleece is still hard to beat on price and warmth compared to most alternatives in cold weather. If the clothing needs to sit against the skin without smelling or feeling clammy, bamboo viscose is the better choice. Together the two fibers cover all of winter's needs effectively.