9.2 Gastric Hair Residence Time

Gastric Hair Residence Time describes how long swallowed hair remains in the stomach before passing onward or being regurgitated.

Longer residence time can increase Hair Entanglement Probability. This does not mean all hairball vomiting is pathological, but frequent vomiting requires boundary judgment.

Hair should generally pass through stool when the pathway is stable. Backtrace returns to Gastric Emptying Speed and upstream food structure.

Primary timing driver.

Grooming and seasonal shedding input.

Aggregation before regurgitation.

Fat timing and physical form from upstream.

upstream food structure

↓

gastric emptying speed

↓

gastric hair residence time

↓

hair entanglement probability

↓

regurgitation or stool passage

Hairball vomiting index and stool hair passage are output signals—not root causes.