The Weighted Blanket Claim, Weighed: Interface Pressure from a 10 Percent Body-Weight Blanket Against the Pressures Its Marketing Invokes

Weighted blankets are sold under the phrase 'deep pressure', with the dose set by a rule of thumb: ten percent of body weight. This paper simply does the division the marketing omits. A blanket of 7.0 kg for a 70 kg sleeper, resting on a stated 0.85 square metres of body surface, produces a mean interface pressure of 0.08 kPa and a modelled peak of 0.18 kPa over bony areas — 2 percent of the 4.27 kPa capillary threshold, and far below the pressures of the hugs and compression garments the advertising evokes. Reaching even 3 kPa of mean pressure would require a blanket of 259.9 kg, which no sleeper could lift onto the bed. The arithmetic does not show that users feel nothing; it shows that whatever they feel is not 'deep pressure' in any sense the phrase is used elsewhere, and the claim as sold does not survive its own numbers. This study is simulated, not measured.