What are Thickeners and Why Are They Used?
Food and liquid thickeners are substances used to increase the viscosity of liquids and foods. They are a primary management tool for individuals with dysphagia, a medical term for difficulty swallowing [1.2.6]. This condition can result from various medical issues, including stroke, neurological disorders, head and neck cancer, and simply the effects of aging [1.3.1]. Dysphagia affects a significant portion of the population, with prevalence estimated to be between 10% and 22% in Americans over 50 [1.3.3]. The purpose of thickening liquids is to slow their movement, allowing the person more time to control the bolus and swallow safely, reducing the risk of aspiration (when food or liquid enters the airway and lungs) [1.6.2].
Is Thickener a Prescription or Over-the-Counter?
Commercial food thickeners are generally available for purchase over-the-counter (OTC) at pharmacies and online retailers [1.2.1, 1.2.2]. Brands like Thick-It, SimplyThick, and others can be bought without a doctor's order [1.2.3, 1.4.3].
However, there are important scenarios where a prescription becomes essential:
- Insurance Coverage: While available OTC, getting a prescription from a doctor may be necessary to see if the cost is reimbursable by Medicare, Medicaid, or private insurance providers [1.2.2, 1.8.1]. Medicare itself often denies coverage for food thickeners, classing them as non-covered grocery products [1.8.6]. Medicaid coverage varies significantly by state, with some states not considering thickeners a medical necessity at all, while others have cost-based reimbursement models [1.8.4, 1.8.5].
- Medical Necessity: For health savings account (HSA) reimbursement, a letter of medical necessity from a doctor is typically required because thickeners are considered a 'dual-purpose' item [1.2.4].
- Professional Guidance: Most importantly, thickeners are usually recommended or 'prescribed' by a Speech-Language Pathologist (SLP) or physician following a swallowing evaluation [1.2.5]. This professional recommendation is critical for determining the exact level of thickness required for safety, as incorrect thickness can still pose risks [1.7.1].
Types of Thickeners: A Comparison
There are two main categories of commercial thickeners: starch-based and gum-based. Each has distinct properties, benefits, and drawbacks.
Starch-Based Thickeners
These are often made from modified cornstarch [1.2.3].
- Pros: They are widely accessible and generally less expensive than gum-based options [1.2.1].
- Cons: They can impart a starchy flavor and a grainy or chalky texture [1.5.4]. The thickness can continue to change over time, becoming thicker the longer it sits [1.5.6]. Starch-based thickeners are also not stable in the presence of saliva, as the amylase enzyme can break them down, reducing their viscosity [1.5.4].
Gum-Based Thickeners
Xanthan gum is a common ingredient in this category [1.5.2].
- Pros: Gum-based thickeners maintain a stable consistency over time and are resistant to salivary amylase [1.5.4, 1.5.6]. They are often described as having a smoother, less sticky mouthfeel and are generally preferred for taste [1.5.4]. They also contain fewer carbohydrates and more fiber compared to starch-based types [1.5.4].
- Cons: They are typically more expensive and may need to be ordered online [1.2.1]. Certain gum-based thickeners, like SimplyThick, are contraindicated for infants under one year old due to a risk of necrotizing enterocolitis (NEC) [1.6.1].
| Feature | Starch-Based Thickeners | Gum-Based Thickeners |
|---|---|---|
| Main Ingredient | Modified Cornstarch [1.2.3] | Xanthan Gum, Guar Gum, etc. [1.5.2] |
| Consistency | Can become thicker over time [1.5.6] | Stable consistency over time [1.5.5] |
| Taste/Texture | Can be grainy, starchy, or chalky [1.5.4] | Smoother, less perceptible flavor [1.5.4] |
| Stability | Degrades with salivary amylase [1.5.4] | Resistant to salivary amylase [1.5.4] |
| Cost | Generally less expensive [1.2.1] | Generally more expensive [1.2.1] |
| Nutrition | Higher in carbohydrates [1.5.4] | Higher in fiber, lower in carbs [1.5.4] |
Understanding Thickness Levels: The IDDSI Framework
To standardize dysphagia diets worldwide, the International Dysphagia Diet Standardisation Initiative (IDDSI) created a framework of 8 levels (0-7) for foods and drinks. For liquids, there are five levels, replacing the old system of "nectar," "honey," and "pudding" thick [1.7.1, 1.7.4].
- Level 0 - Thin: Flows like water [1.7.3].
- Level 1 - Slightly Thick: Thicker than water, often used for infants. It is thinner than the old "nectar" consistency [1.7.1].
- Level 2 - Mildly Thick: Corresponds to the old "nectar-thick" level. It flows off a spoon and can be sipped from a cup [1.7.2, 1.7.3].
- Level 3 - Moderately Thick: Corresponds to the old "honey-thick" level. It can be eaten with a spoon but is too thick to drink through a standard straw [1.7.2, 1.7.3].
- Level 4 - Extremely Thick: Corresponds to the old "pudding-thick" level. It holds its shape on a spoon and does not require chewing [1.7.2, 1.7.3].
A healthcare professional, typically an SLP, will determine the appropriate IDDSI level for a patient [1.7.1].
Risks and Considerations
While beneficial, thickeners are not without risks. Potential side effects include constipation, gassiness, or loose stools [1.6.1]. More significant concerns include reduced fluid intake leading to dehydration, poor palatability affecting quality of life, and reduced bioavailability of certain medications [1.6.2, 1.6.3]. In infants, particularly premature ones, some thickeners have been linked to an increased risk of necrotizing enterocolitis (NEC), a serious intestinal disease [1.6.1, 1.6.6]. Therefore, medical guidance is paramount, and thickeners should never be used without a professional recommendation, especially in pediatric populations [1.6.1].
Conclusion
So, is thickener a prescription? No, not for the purpose of purchasing it. Most are available over-the-counter. However, the recommendation for a thickener, including the specific type and consistency, should always come from a qualified healthcare professional like a doctor or Speech-Language Pathologist [1.2.5]. A formal prescription document is often the key to unlocking insurance or Medicaid coverage, although this is not guaranteed and varies widely [1.8.3, 1.8.4]. Using these products correctly and under medical supervision is critical for managing dysphagia safely and effectively.
