How and why thickened liquids improve swallowing safety and swallowing efficiency
Swallowing is a complex process. When the ability to safely swallow regular liquids is impaired, liquids are thickened to slow flow, in an effort to maintain oral hydration. A combination of bolus properties such as viscosity, yield stress, bolus cohesion and slipperiness facilitate safe passage of the bolus. Studies have demonstrated that these features, examined at various levels of thickness, promote safe swallowing. The literature demonstrates that xanthan gum has features that are most appropriate to facilitate swallowing safety when objectively compared with other thickeners. It is imperative that dysphagia clinicians evaluate individuals with dysphagia to determine the ‘thickness dose’ that is most appropriate to treat each patient’s individual needs. A range of thickness levels are required to meet the variability in dysphagia presentations.