Swallowing behavior response to semi-solid foods with different textural properties in healthy older adults: an...

Semi-solid foods are widely consumed by older adults, yet the influence of their physical properties on swallowing remains unclear.

To examine how variations in shape retention and spreadability affect swallowing in adults aged ≥75 years.

An open-label randomized crossover trial with two food tests.

Controlled experimental setting.

Test 1 enrolled 21 adults and Test 2 enrolled 28; after exclusions, 14 and 16 were analyzed (mean ages 81.6 and 78.6 years).

Participants ingested three semi-solid foods (P, Q, S) differing in physical properties.

Primary outcomes were oral processing time (OPT) and swallowing duration (SD), measured by a neck-worn electronic stethoscope and synchronized video. Secondary outcomes were subjective ratings of swallowing ease and food properties. Medians of five bites were analyzed, and first-fifth bite differences assessed.

Subjective ratings differed only in collectability in Test 2. In Test 1, OPT was longer for P than Q (median difference 1.04 s, 95 % CI 0.15-2.04; p = 0.030). In Test 2, OPT was longer for S than P (median difference -1.88 s, -2.81 to -0.74; p = 0.001). SD did not differ significantly. With repeated swallows, OPT variance increased and SD variance decreased for P and Q, while both increased for S.

None observed.

Semi-solid food properties affect swallowing in older adults. Shape retention contributes to distinct swallowing patterns, supporting individualized food selection to promote safe intake.

UMIN000053442, UMIN000056840.