Thickened Liquids

Dysphagia is an impairment that affects the normal swallowing process secondary to neurological or structural problems.  Often, this means a person is unable to safely and/or efficiently eat or drink (especially thickened liquids). Statistics from the American Speech and Hearing Association on who is affected by dysphagia:

  • 22% in adults over 50 years of age
  • Up to 68% for residents in long-term care settings
  • CVA:  >50%
  • TBI: 26-71%
  • Parkinson’s disease: 50-92%
  • ALS: 100%
  • Dementia: most common in moderate-severe impairment levels

Approximately one-third of patients with dysphagia develop a serious condition known as aspiration pneumonia and 60,000 individuals die each year from such complications. Speech-Language Pathologists (SLPs) know these statistics well and are trained to diagnose and treat dysphagia. An important part of the SLPs treatment may include diet modification to either the texture of a person’s food or the viscosity of the liquids they drink.

The SLP may recommend thickening liquids to either nectar or honey consistency in order to decrease the risk of aspiration, however, this does not come without its own challenges. Making a recommendation to provide only thickened liquids raises concerns of noncompliance, dehydration, malnutrition, and overall impact on a person’s quality of life.

According to the European Society for Swallowing Disorders in 2016 “there is evidence for increasing viscosity to reduce the risk of airway invasion and that is a valid management strategy for OD. However, new thickening agents should be developed to avoid the negative effects of increased viscosity on residue, palatability, and treatment compliance.”¹Historically, all thickened liquids used with a starch agent because it was inexpensive and readily available. While this is still true, starch comes with significant limitations:

  • Not stable and may continue to thicken the drink over time
  • Has a “gritty” texture
  • Can have a cloudy appearance to the drink
  • May increase pharyngeal residue and be more difficult to clear if aspirated

Recently, an update of the science of thickening agents provided a solution to many of the issues related to thickened liquids. Xanthan-based thickeners have provided a starch alternative that can significantly improve safety and quality of life.

  • Does not continue to thicken over time
  • There is no change in the way the drink looks (water remains clear)
  • The taste of the drink remains the same without having a gritty quality
  • It is suggested that there is less risk of pharyngeal residue and may be easier to clear if aspirated

It is important for speech-language pathologists, caregivers, and patients managing dysphagia to learn about the options when choosing thickened liquids. Clearly, not all thickening agents are created equal. Would you like to talk more about speech therapy, thickened liquids, or more?  I’d love to hear your thoughts.  Please use the comment box below.

About the Author: Originally from Port Jefferson, New York, Jennifer Baquet Maher, MA, CCC-SLP has a Master’s Degree from St. John’s University’s Communication Sciences and Disorders program.   In her spare time, Jen enjoys family, cooking, and traveling.

Reference:1- Newman, R., Vilardell, N., Clavé, P., & Speyer, R. (2016). Effect of bolus viscosity on the safety and efficacy of swallowing and the kinematics of the swallow response in patients with oropharyngeal dysphagia: White paper by the European Society for swallowing disorders (ESSD). Dysphagia, 31(2), 232-249. doi: