What is the Iddsi diet and who is it for?

December 25, 2025 •

3 min read

According to the International Dysphagia Diet Standardisation Initiative (IDDSI), approximately 8% of the world's population is affected by swallowing difficulties, known as dysphagia. The Iddsi diet is a global, standardized framework of modified food textures and thickened liquids developed to ensure the safety and nutritional needs of these individuals. It provides a common language for caregivers, healthcare professionals, and patients to describe and prepare safe foods and drinks.

Quick Summary

The International Dysphagia Diet Standardisation Initiative (IDDSI) created a global framework with 8 levels of modified food textures and thickened liquids. This system uses numbers, colors, and descriptors to classify diets for people with swallowing difficulties, or dysphagia, making meal preparation and communication safer and clearer.

Key Points

Global Standardization: IDDSI is the International Dysphagia Diet Standardisation Initiative, a global system for classifying modified food and drinks for those with swallowing difficulties.
Eight Levels: The framework includes a continuum of 8 levels (0–7) covering both liquids and foods, each with distinct characteristics.
Food Safety: The system provides clear definitions and testing methods to improve patient safety and reduce risks like choking and aspiration pneumonia.
Reduced Confusion: IDDSI replaces outdated, facility-specific terminologies with a universal language, ensuring consistent care across all settings.
Practical Testing: Simple, reliable tests like the Fork Drip Test and Spoon Tilt Test confirm that food and drinks meet the required consistency.
Multidisciplinary Development: The framework was developed by a diverse group of healthcare professionals, ensuring it is comprehensive and evidence-based.

What is the IDDSI Framework?

IDDSI, which stands for the International Dysphagia Diet Standardisation Initiative, was established by a global committee of volunteers from diverse professional backgrounds, including dietetics, speech pathology, and medicine. The initiative was founded in 2012 and, after extensive research and consultation, published its standardized framework in 2015. The main purpose of the IDDSI framework is to replace older, inconsistent terminology for modified diets with a universal system. This reduces the risks of choking, aspiration pneumonia, and dehydration often associated with dysphagia.

The framework consists of a continuum of eight levels, from 0 to 7, each identified by a number, a text label, a color code, and specific testing methods. Drinks are classified from Levels 0–4, while foods are classified from Levels 3–7. This overlap at Levels 3 and 4 indicates similar characteristics in both fluid and food consistency.

How are IDDSI levels determined?

To ensure accuracy and safety, the IDDSI framework includes simple testing methods that can be performed by caregivers, clinicians, or patients. These tests are used to confirm that the food or liquid meets the criteria for its assigned level before consumption. The IDDSI website offers detailed instructions and resources for these tests. For fluids, a simple flow test is used, typically with an IDDSI syringe to measure the amount of fluid that flows out over a specific time. For foods, tests include the fork drip test, spoon tilt test, and fork pressure test.

IDDSI Food Levels Explained

Level 7 – Regular & Easy to Chew: Regular food with normal textures is suitable for those who do not have swallowing difficulties. The 'Easy to Chew' subcategory features softer textures that still require chewing but are easier to manage. Foods should be soft, tender, and moist throughout.
Level 6 – Soft & Bite-Sized: Foods are soft, tender, and moist, with a maximum particle size that reduces choking risk. For adults, pieces must be no larger than 1.5cm x 1.5cm. These foods can be broken apart with fork pressure.
Level 5 – Minced & Moist: Food is finely minced into small, moist lumps with no thin liquid. Minimal chewing is required. The food must hold its shape on a spoon but easily fall apart with light fork pressure.
Level 4 – Pureed: Food is smooth with no lumps, with a texture similar to extremely thick drinks. It must be able to be eaten with a spoon and should hold its shape.
Level 3 – Liquidised: Food is blended to a smooth, lump-free liquid that is thick enough to pour from a spoon. It cannot be eaten with a fork as it will flow through the prongs.

IDDSI Drink Levels Outlined

Level 0 – Thin: Regular, unthickened liquids like water, tea, and juice.
Level 1 – Slightly Thick: Thicker than water, requiring minimal effort to drink from a cup or straw.
Level 2 – Mildly Thick: Flows more slowly than slightly thick liquids and can be sipped from a cup.
Level 3 – Moderately Thick: Pours from a spoon but cannot be drunk from a cup. This level can be consumed from a cup, but with effort.
Level 4 – Extremely Thick: Holds its shape and requires a spoon to eat or drink.

Comparison of IDDSI levels


IDDSI Level	Food Characteristics	Drink Characteristics
Level 0 (Thin)	N/A	Fast flowing, like water
Level 1 (Slightly Thick)	N/A	Flow is slightly slower than water
Level 2 (Mildly Thick)	N/A	Flow is slower than Level 1, sippable with some effort
Level 3 (Moderately Thick & Liquidised)	Blended to a smooth, lump-free liquid	Flows from a spoon, not from a cup
Level 4 (Extremely Thick & Pureed)	Smooth texture, no lumps, holds its shape	Holds its shape, must be eaten with a spoon
Level 5 (Minced & Moist)	Small, moist lumps, holds shape on spoon	N/A
Level 6 (Soft & Bite-Sized)	Soft, tender, moist, and bite-sized pieces	N/A
Level 7 (Regular & Easy to Chew)	Regular textures, potentially softer options	N/A

Conclusion

The IDDSI framework serves as an invaluable tool for ensuring patient safety and quality of life for individuals with dysphagia. By standardizing terminology and providing straightforward testing methods, it minimizes confusion and promotes consistent care across different settings and cultures. The framework empowers healthcare professionals, caregivers, and patients to make informed decisions about diet modifications, helping to prevent potentially serious health complications such as aspiration and dehydration. Successful implementation of the Iddsi diet can significantly improve nutritional intake and the overall dining experience for those with swallowing difficulties, demonstrating a crucial step forward in patient care. For more information, the official IDDSI website is an excellent resource.

Frequently Asked Questions

IDDSI stands for the International Dysphagia Diet Standardisation Initiative.

The Iddsi diet is for individuals of all ages who have dysphagia, or swallowing difficulties.

The IDDSI framework consists of a continuum of eight levels, from 0 to 7.

Yes, drinks are classified from Levels 0 to 4, while foods are classified from Levels 3 to 7. There is an overlap at Levels 3 and 4.

The primary goal is to improve safety for individuals with dysphagia by providing a standardized, global terminology for modified food and drink textures.

Yes, IDDSI includes simple, practical tests using standard items like forks and spoons that can be easily performed by caregivers to verify food and drink consistency.

No, IDDSI is a more recent, globally standardized framework that replaces previous, inconsistent national guidelines like the NDD.