Pillow Height and Breathing: The Neck-Neutral Arithmetic

The pillow is airway geometry equipment: wrong loft kinks the neck that carries your night's breathing — right loft disappears from notice.

The under-head engineering chapter.

The Neck-Neutral Arithmetic

The alignment principle: the cervical spine held NEUTRAL (head level with the torso's line — neither propped chin-to-chest nor dropped back), because flexion-and-extension both narrow the pharynx's geometry (the elevation chapter's pillow-stacking warning being this arithmetic violated), and morning neck-stiffness doubling as geometry feedback. The pillow's job: fill the head-to-mattress gap your position creates — no more.

Position-Specific Lofts

The sizing table: SIDE sleepers need the tallest fill (shoulder-width's gap — medium-to-high lofts keeping the head level; the between-knees companion squaring the chain), BACK sleepers run lower (modest lofts cradling the curve without chin-push — with the snoring note that back-position itself carries the position chapter's fine print), STOMACH sleepers thinnest-to-none (the position's neck-rotation tax arguing for retraining more than purchasing), and combination sleepers favouring adjustable-fill solutions (shredded cores shaped per position).

Material-and-Allergy Notes

The fill file: MEMORY foams hold shape (off-gassing's airing-protocol per the furniture chapter), LATEX's resilient-and-mite-resistant case (latex-allergy households excepted), DOWN's mouldable softness (allergen-washable covers mandatory; true down-allergy rarer than assumed but real), SHREDDED-fill adjustability (the loft-tuning winner), and the universal allergy layer — encasements-and-hot-wash covers per the mite chapter regardless of core.

The Replacement Calendar

The lifecycle honesty: pillows collapse-and-colonise over 1-3 years (support sagging as mite-and-skin load builds — the fold-test: a folded pillow that stays folded has retired), covers-washed-weekly extending cores, and the purchase protocol: loft matched to position first, material second, trial-nights honoured where sellers allow.

Pillow verdict: fill the gap your position makes, encase whatever fills it, and believe the fold-test's verdict.