* Natural hollow fibers like silk and wool contain microscopic air channels that create superior temperature regulation and moisture management compared to solid fibers like cotton and linen
* A single wool fiber can contain up to 2,500 air chambers per inch, while silk has a unique triangular cross-section with three hollow chambers that create its characteristic sheen
* Hollow fibers can absorb significant moisture while still feeling dry. Wool can absorb 30% of its weight in moisture without feeling wet, unlike cotton, which becomes heavy and cold when damp
* Eucalyptus-derived hollow fibers (Tencel/Lyocell) represent a modern, sustainable alternative that combines natural benefits with manufacturing precision, using just a fraction of the water required for cotton production
* While hollow fiber materials like silk and wool typically cost more upfront, they often prove more economical over time due to superior longevity — a silk pillowcase can last five years compared to a cotton one lasting only one year”
https://organicconsumers.org/why-natural-hollow-fibers-outperform-traditional-materials/