The International Dysphagia Diet Standardisation Initiative (IDDSI)
The International Dysphagia Diet Standardisation Initiative (IDDSI) provides a globally recognized framework with standardized terminology for modifying food and liquid textures. This eight-level system (0–7) helps healthcare professionals, caregivers, and individuals with dysphagia to communicate and implement a diet that promotes safe swallowing. Foods are classified from Level 3 (Liquidised) to Level 7 (Regular), while liquids are categorized from Level 0 (Thin) to Level 4 (Extremely Thick). An individual's specific IDDSI level is determined by a clinical assessment from a speech-language pathologist.
IDDSI Food Texture Levels
Understanding the characteristics of each food texture level is essential for proper diet management. The IDDSI framework provides reliable tests, like the Fork Pressure Test, to ensure food meets the criteria for each level.
- Level 4 (Pureed): Foods at this level require no chewing and are smooth, with no lumps or separated liquid. They are typically thick enough to hold their shape on a spoon but can be piped or molded. Good examples include smooth pureed meats, vegetables, and fruits like applesauce.
- Level 5 (Minced & Moist): These foods are soft and moist with small, visible lumps that are easily mashed with a fork or tongue pressure. The particle size for adults is limited to 4mm. This level includes minced meats with gravy, mashed fruits, and fully softened cereals.
- Level 6 (Soft & Bite-Sized): This texture is soft, tender, and moist, with bite-sized pieces for adults no larger than 15mm. It requires chewing and can be broken down with a fork. Suitable options include tender cooked meats, moist fish, and steamed vegetables cut into small pieces.
- Level 7 (Regular/Easy to Chew): This level includes normal, everyday foods. The Easy to Chew category is a subgroup of Level 7 for individuals who need softer regular foods due to chewing fatigue, but without specific particle size restrictions. Examples include soft bread or soft, tender cooked meat.
IDDSI Liquid Thickness Levels
The IDDSI framework categorizes liquids based on their viscosity, from thin to extremely thick. Commercial thickening agents, often starch- or gum-based, are used to achieve the desired consistency.
- Level 0 (Thin): Water, juice, coffee, and other standard beverages.
- Level 1 (Slightly Thick): Thicker than water but flows freely from a spoon.
- Level 2 (Mildly Thick): Pours quickly but slower than thin liquids, similar to nectar.
- Level 3 (Moderately Thick): Flows slowly off a spoon, comparable to honey.
- Level 4 (Extremely Thick): Holds its shape on a spoon and cannot be drunk from a cup.
Practical Food Preparation Techniques
Successful dysphagia management relies on correct food preparation. Here are some key techniques:
- Pureeing: Use a blender, food processor, or immersion blender to achieve a smooth, uniform consistency for Level 4 foods. Always add extra liquid, such as broth, milk, or sauce, to ensure the puree is moist and cohesive.
- Mincing and Moistening: For Level 5 foods, use a food processor or a mincer. For home preparation, a fork or potato masher can be used on softer items. Ensure plenty of gravy, sauce, or butter is added to keep the food moist and help it bind together.
- Chopping and Dicing: For Level 6 foods, ensure all ingredients are cooked until very tender and then cut into the appropriate bite-sized pieces (1.5 cm for adults). A knife and cutting board are suitable for this task.
- Thickening Liquids: Always follow the manufacturer's instructions for thickening powders, as different brands and thickener types (e.g., starch-based, xanthan gum-based) can require different ratios. Test the thickness with the IDDSI Flow Test to confirm the correct level.
- Adding Moisture: For any modified texture, moisture is key. Soups, sauces, gravies, and milk are excellent for this. Never serve dry, crumbly, or sticky foods, as they are a major aspiration risk.
Foods and Textures to Avoid
To reduce the risk of choking and aspiration, certain foods and textures should be completely avoided on modified diets. These include:
- Dry, crumbly, and sticky foods (e.g., crackers, dry toast, peanut butter).
- Hard, crunchy foods (e.g., nuts, popcorn, raw vegetables).
- Stringy or fibrous foods (e.g., pineapple, celery, peas).
- Foods with tough skins or husks (e.g., corn, grapes).
- Mixed consistencies, where thin liquid is combined with a solid component (e.g., vegetable soup, cereal with thin milk). The liquid and solid can separate and be aspirated.
- Chewy items (e.g., caramel, gummy candies).
Comparison Table: IDDSI Levels 4, 5, and 6
| Feature | Level 4 (Pureed) | Level 5 (Minced & Moist) | Level 6 (Soft & Bite-Sized) |
|---|---|---|---|
| Chewing | No chewing required | Minimal chewing required | Chewing required |
| Texture | Smooth, uniform, lump-free | Soft and moist with small, soft lumps | Soft, tender, and moist |
| Particle Size (Adult) | Not applicable (smooth) | Max 4mm (minced) | Max 15mm (bite-sized) |
| Moisture Content | Cohesive; no separated thin liquid | Moist; no separated thin liquid | Moist; no separated thin liquid |
| Preparation Method | Blended until smooth | Minced or mashed, with added moisture | Cooked tender and chopped |
| Key Food Examples | Applesauce, pureed meat, mashed potatoes | Minced meat with gravy, mashed banana | Cooked fish, tender vegetables |
