Thickeners are commonly used for a medical condition called dysphagia, or difficulty swallowing. For these patients, thickening liquids like water or juice helps slow their movement down the throat, making swallowing safer and preventing aspiration into the lungs. While most food thickeners are derived from natural sources such as starches (like modified maize) and gums (like xanthan or guar gum), their safety depends entirely on correct preparation and consumption. The effects of eating thickener vary dramatically depending on whether it is ingested in its raw, powdered form or consumed as a properly mixed part of a thickened liquid.
The Immediate Danger of Eating Raw Thickener Powder
The most severe and immediate risk comes from ingesting thickener powder directly, without mixing it thoroughly into a liquid first. The powder is highly absorbent and reacts instantly with moisture.
- Asphyxiation Risk: When swallowed dry, the powder mixes with saliva in the mouth and throat, expanding rapidly to create a gelatinous mass that can block the airway. This poses a severe choking hazard and has tragically led to deaths, prompting patient safety alerts in healthcare settings.
- Safe Storage: Incidents have occurred in care facilities when cognitively or visually impaired individuals mistook the powder for a drink. Because of this, it is crucial to store thickener powder securely out of reach of vulnerable individuals and children.
Side Effects of Consuming Properly Mixed Thickeners
When correctly mixed into food or drinks, thickeners are generally considered safe for most people. However, for those who rely on them long-term, particularly for dysphagia management, side effects can occur due to the altered properties of the food and drink.
Gastrointestinal Issues
Many thickeners, particularly gum-based types like xanthan gum, are essentially soluble fiber. When consumed regularly, this can cause a range of digestive disturbances.
- Bloating and Gas: The fermentation of fiber by gut bacteria can lead to increased gas production and bloating.
- Altered Bowel Habits: While fiber can promote regularity, it can also lead to constipation or, in some cases, diarrhea, depending on the individual and the type of thickener.
Dehydration Risk
Paradoxically, thickened liquids can increase the risk of dehydration, even though the body absorbs the water from them effectively.
- Reduced Intake: Patients with dysphagia often dislike the taste and texture of thickened liquids, leading them to drink less overall.
- Early Satiety: Thickened liquids can induce a greater feeling of fullness sooner, which contributes to lower overall fluid and food intake.
Affecting Medication Absorption
Thickened liquids can interfere with the way the body processes and absorbs oral medications. This is a complex interaction influenced by the type of thickener, its viscosity, and the drug itself.
- Delayed Dissolution: Thickened fluids can slow the disintegration and dissolution of oral tablets or capsules, potentially reducing or delaying their absorption.
- Thickener Type Matters: Some studies suggest that negatively charged, gum-based thickeners like xanthan gum may have a more pronounced effect on drug dissolution than starch-based ones.
- Specific Drug Interactions: A notable interaction exists between starch-based thickeners and macrogol (polyethylene glycol) laxatives, which renders the mixture watery instead of thick.
Risks for Infants and Other Specific Populations
Certain groups face unique risks from thickener consumption.
- Necrotizing Enterocolitis (NEC): Xanthan gum-based thickeners, like SimplyThick, have been linked to a serious and potentially fatal intestinal disease in premature infants. For this reason, many health professionals advise against their use in this population.
- Underlying Conditions: Patients with certain conditions, such as those with gastrointestinal disorders, may have altered bowel function that can be exacerbated by thickeners.
- Quality of Life: Research has shown that being restricted to thickened fluids can negatively impact a person's quality of life and satisfaction with eating and drinking.
Comparison of Thickener Types and Ingestion Methods
| Feature | Raw Thickener Powder | Properly Mixed Thickener (Starch-Based) | Properly Mixed Thickener (Gum-Based) |
|---|---|---|---|
| Immediate Risk | Severe asphyxiation/choking hazard | Safe when mixed and swallowed correctly | Safe when mixed and swallowed correctly |
| Effect on Saliva | Reacts instantly with moisture to create a mass | Broken down by amylase enzyme in saliva, can thin over time | Resistant to amylase, maintaining stable thickness in saliva |
| Primary Side Effects | N/A (immediate, life-threatening risk) | Potential constipation, bloating; less impact on medication than gums | Potential bloating, gas, altered bowel habits; more impact on medication |
| Nutritional Impact | N/A | Can add minor calories | Adds soluble fiber; low calories |
| Taste/Texture | Chalky, dry taste if briefly sampled; immediate hazard if ingested | May impart a grainy, starchy texture and flavor | Can create a slick, cohesive texture; flavor neutral |
Conclusion
While thickeners are an essential tool for managing dysphagia and ensuring safe eating and drinking for vulnerable individuals, they are not without risks. The most critical danger is the ingestion of dry powder, which poses an immediate and fatal choking hazard. For those consuming properly mixed thickeners long-term, side effects can include gastrointestinal discomfort, potential dehydration due to reduced fluid intake, and altered medication absorption. It is imperative that thickening agents are stored safely, prepared according to manufacturer and healthcare professional instructions, and that their use is carefully monitored, particularly in infants and individuals taking multiple medications. Always consult with a healthcare provider, such as a Speech-Language Pathologist or dietitian, to ensure that thickener use is safe and appropriate for specific dietary and medical needs.
For more information on the dangers of accidental ingestion of thickening powder, refer to the patient safety alert from NHS England.
