The Effect of Capsaicin-Containing Food on the Swallowing Response

The purpose of this study was to determine the effect of regular ingestion of capsaicin-containing food that is easily available in everyday life on the latency of the swallowing response (LSR). Pickled Napa cabbage was selected as the food for the present study. One portion (10 g) of pickled Napa cabbage provides 1.5 µg of capsaicin. Participants ingested pickled Napa cabbage (10 g) before every meal for 20 days (days 1–20). LSR was measured pre-intervention (day 0) and post-intervention (day 21). The participants then followed their regular diet, without foods containing red pepper, from day 21 to day 27, and LSR was measured on day 28 (follow-up LSR). Sixteen elderly participants (two male, 14 female; age 81.6 ± 9.39 years) and 10 young participants (all female; age 21.6 ± 0.52 years) participated in the study. The pre-intervention LSR was 2.04 ± 1.60 s in elderly participants and 1.27 ± 0.27 s in young participants. In the elderly group, the post-intervention LSR (day 21) was 1.47 ± 1.05  the follow-up LSR (day 28) was 1.99 ± 1.80 s (p = 0.044 and 0.502, respectively, compared to pre-intervention). In the young group, the post-intervention and follow-up LSR values were 1.07 ± 0.20 s and 1.04 ± 0.10 s, respectively (p = 0.016 and 0.038, respectively, compared to pre-intervention). Swallowing function was improved by pickled Napa cabbage containing capsaicin, but capsaicin supplementation may need to be maintained to have an ongoing effect.