The IDDSI Framework: Ending Confusion with Standardisation
For many years, inconsistent terminology for modified diets created risks for individuals with dysphagia, or swallowing difficulties. Terms like "nectar thick" could be interpreted differently across facilities and even between healthcare professionals, leading to potential health complications. In response, the International Dysphagia Diet Standardisation Initiative (IDDSI) was developed to provide a common, global language with clear, objective testing methods. The IDDSI framework uses eight levels, numbered 0 to 7, to describe the continuum of food and drink textures. This article will clarify where the old "nectar thick" consistency fits into this new, safer system.
Nectar Thick Corresponds to IDDSI Level 2: Mildly Thick
The short and most direct answer is that the liquid consistency previously described as nectar thick is now most commonly referred to as Mildly Thick, or IDDSI Level 2. This level is for liquids that are thicker than water but can still be sipped from a cup. They run quickly off a spoon, leaving a thin coating, and require some effort to drink through a straw. This is notably different from "Slightly Thick" liquids (Level 1), which flow faster, or "Moderately Thick" liquids (Level 3), which are thicker and pour more slowly, like honey.
Some older references might associate "nectar thick" with IDDSI Level 1 (Slightly Thick), creating some confusion. However, the IDDSI framework intended for Mildly Thick (Level 2) to be the direct equivalent of the old nectar-like consistency. Therefore, when a prescription calls for "nectar thick" liquids, the safest and most accurate interpretation is to prepare liquids to the IDDSI Level 2 standard.
The Importance of the IDDSI Flow Test
One of the most valuable aspects of the IDDSI framework is the inclusion of simple, objective testing methods. This moves beyond subjective descriptions and allows for a reliable verification of liquid consistency. The primary test for thickened liquids is the IDDSI Flow Test, which uses a 10 mL syringe to measure the flow rate.
Here’s how to perform the test for Mildly Thick (Level 2) liquids:
- Take a 10 mL Luer slip syringe, remove the plunger, and cover the nozzle with your finger.
- Pour 10 mL of the liquid to be tested into the syringe.
- Remove your finger and, using a stopwatch, time exactly 10 seconds.
- After 10 seconds, immediately cover the nozzle again and measure the amount of liquid remaining in the syringe.
- For a Mildly Thick liquid (Level 2), the amount of liquid left should be between 4 mL and 8 mL.
This simple, repeatable test ensures that the liquid's consistency is precisely correct, which is critical for patient safety.
The Complete IDDSI Liquid Spectrum
The IDDSI framework includes a comprehensive spectrum for liquids, not just the levels associated with the old "nectar thick" terminology. The full liquid continuum from thinnest to thickest includes:
- IDDSI Level 0 (Thin): Flows like water. Includes water, tea, coffee, and sodas.
- IDDSI Level 1 (Slightly Thick): Thicker than water but thinner than Mildly Thick. Requires a little more effort to drink.
- IDDSI Level 2 (Mildly Thick): The "nectar thick" equivalent, similar to a thick milkshake or creamy soup.
- IDDSI Level 3 (Moderately Thick): Pours more slowly, similar to honey. Can be drunk from a cup but is easier to manage with a spoon. This level also overlaps with liquidized foods.
- IDDSI Level 4 (Extremely Thick): Holds its shape and is not pourable. Must be eaten with a spoon and has a smooth texture. This level overlaps with pureed foods.
Comparison of Old NDD Terminology and IDDSI Levels
To further clarify the transition, the following table compares the older National Dysphagia Diet (NDD) labels with their corresponding IDDSI levels.
| Old NDD Terminology | IDDSI Level | IDDSI Description | IDDSI Flow Test Result (10 mL syringe) |
|---|---|---|---|
| Thin-like | Level 0 | Thin | Less than 1 mL left after 10 sec |
| Nectar-like | Level 2 | Mildly Thick | Between 4 and 8 mL left after 10 sec |
| Honey-like | Level 3 | Moderately Thick | No less than 8 mL left after 10 sec |
| Pudding-like | Level 4 | Extremely Thick | 10 mL left after 10 sec, no flow |
It is clear from this comparison that IDDSI offers a more precise and standardized approach than the older, more ambiguous NDD descriptions. This new framework reduces the risk of misinterpretation, which is a major step forward for patient safety. For further resources and information on the framework, visit the IDDSI website.
Conclusion
The term "nectar thick" has been replaced by the more specific and objective terminology of the IDDSI framework. The most accurate corresponding level is Mildly Thick (IDDSI Level 2). This standardization helps to ensure that individuals with dysphagia receive a consistent and safe diet tailored to their specific needs. Using the IDDSI Flow Test is the recommended method to verify that liquids are prepared to the correct thickness, moving away from subjective descriptions and toward a global standard of care. Always consult with a healthcare provider to determine the appropriate liquid thickness level for a particular individual.
