There are several levels of consistency/viscosity and these have historically varied by country, although the launch of the International Dysphagia Diet Standardisation Initiative (IDDSI)[2] aims to remove this variation.
According to the IDDSI, the thickness of a drink can be tested by measuring the amount that pours out of a 10ml syringe in 10 seconds.
Vendors also offer pre-thickened liquids such as water, juice, and milk in individual serving sized cartons.
Some commercial thickeners use modified maize starch, which helps support hydration and nutritional levels, while others use xanthan gum.
There is no good evidence that thickening liquids reduces pneumonia in dysphagia (swallowing problems) and it may be associated with poorer hydration and with an adverse effect on quality of life.