Numerous studies have explored surface myoelectric signals, swallowing sounds, and cervical ultrasound video, using one or two of these modalities in isolation to evaluate swallowing. However, despite the limited temporal resolution of each modality, no study has examined simultaneous integration of all three. In our previous work, we conducted a multimodal analysis combining these signals into a single integrated stream to capture the temporal dynamics of swallowing across the oral, pharyngeal, and esophageal phases. Specifically, we identified temporal trends spanning the initiation of food mass movement, onset of laryngeal elevation, opening of the esophageal orifice, and cessation of food transport. In the present study, we investigated age- and sex-related variations in swallowing characteristics―factors not addressed in our previous work. This analysis revealed two key findings: first, swallowing duration increased with age; second, a decline in swallowing function emerged in certain phases beginning at approximately age 40. Additionally, males exhibited longer swallowing durations than females. These findings support the potential development of a non-invasive diagnostic system as an alternative to videoendoscopy and videofluoroscopy, which are not feasible for frequent assessments and require specialized expertise.