Can coke be thickened? A Nutrition and Dysphagia Diet Guide

October 16, 2025 •

5 min read

For individuals with dysphagia, or difficulty swallowing, thickened liquids are often a necessary part of a nutrition diet to prevent aspiration. This medical requirement raises a common question for patients: Can coke be thickened? The answer is yes, with the right products and techniques, but it comes with significant dietary considerations.

Quick Summary

This article explores the process of thickening carbonated beverages like Coke, detailing suitable commercial thickeners such as gum-based gels. It explains the medical context of dysphagia and why thickened liquids are essential for safe swallowing. The guide also analyzes the nutritional drawbacks of including soda in a diet and outlines potential health risks, emphasizing that professional dietary advice is paramount.

Key Points

Possibility of Thickening Coke: Carbonated beverages like Coke can be thickened using specific commercial products, though it requires careful technique to manage the fizz.
Optimal Thickener Choice: Gum-based gel thickeners, often containing xanthan gum, are the best choice for thickening carbonated drinks as they preserve texture, clarity, and some carbonation.
Serious Health Risks: Consuming thickened cola, especially regular versions, introduces empty calories and high sugar, which can harm overall health, particularly for those with limited intake.
Non-Nutritious Content: Both regular and diet Coke lack essential vitamins, minerals, and nutrients, making them a poor choice for a balanced nutrition diet.
Dehydration Risk: Patients on thickened fluid diets, including those consuming thickened cola, are at a higher risk of dehydration due to poor palatability and reduced intake.
Superior Alternatives: Healthier options for thickened drinks include fruit juices, infused water, thickened milk, and smoothies, which offer better hydration and nutritional value.
Medical Guidance is Critical: All dietary changes involving thickened liquids, especially for dysphagia, should be made under the supervision of a healthcare professional like a dietitian or speech-language pathologist.

Understanding the Need for Thickened Beverages

Thickened liquids are a dietary modification prescribed by healthcare professionals, such as speech-language pathologists (SLPs) and dietitians, for individuals with dysphagia. This condition impairs swallowing, which can lead to thin liquids entering the airway instead of the esophagus, a dangerous event called aspiration. By increasing the viscosity of beverages, thickened liquids slow their movement, providing the patient more time to prepare for and execute a safe swallow.

The International Dysphagia Diet Standardisation Initiative (IDDSI) provides a framework for different levels of thickness, from 'mildly thick' (nectar) to 'extremely thick' (pudding). For many patients, adhering to a prescribed thickness level is a critical aspect of their care plan. This often means modifying a wide range of drinks to the correct consistency, which is why people often inquire about thickening everyday beverages like Coke.

The Challenge of Thickening Carbonated Drinks

Attempting to thicken a carbonated beverage like Coke presents a unique challenge due to its dissolved carbon dioxide. Adding thickeners to fizzy drinks can cause excessive foaming and a loss of carbonation. The vigorous stirring required to dissolve some powder thickeners often accelerates this process. However, specific techniques and products have been developed to mitigate this issue, allowing for the successful thickening of cola and other sodas.

Proper technique involves adding the thickener to a pre-portioned amount of soda while stirring carefully to manage the fizz. Letting the liquid settle for a few minutes before final mixing is also a crucial step to achieve the correct consistency without overwhelming foam.

Commercial Thickeners and Their Impact on Viscosity

Commercial thickening agents come in various forms, including powders and pre-mixed gels. Their effectiveness and impact on the final product differ significantly, particularly with carbonated beverages. Choosing the right type of thickener is essential for achieving the desired outcome.

Types of Thickeners

Starch-based powders: Traditionally the most common type, these are often derived from modified cornstarch. When mixed, they can create a cloudy, sometimes grainy texture and may continue to thicken over time. For carbonated drinks, they are known to cause a complete loss of fizz. A significant drawback is that the enzyme amylase in saliva can break down starch, potentially causing the liquid to thin out in the mouth.
Gum-based powders (e.g., Xanthan Gum): These thickeners are formulated using xanthan gum, a bacterial polysaccharide. Gum-based thickeners are often preferred for carbonated beverages as they can better retain carbonation and produce a clear, stable, and smooth consistency. They are also amylase-resistant, meaning saliva will not cause the thickened liquid to thin.
Gel-based thickeners: Products like SimplyThick, which are xanthan gum-based gels, offer high convenience and control. They are easier to mix into liquids, including carbonated ones, with less clumping or foaming. Studies have found gel thickeners like SimplyThick to produce the most desirable result when thickening cola.

Thickener Comparison Table


Feature	Starch-Based Powder (e.g., Thick-It)	Gum-Based Powder (e.g., Xanthan Gum)	Gel-Based (e.g., SimplyThick)
Effect on Carbonation	Causes complete loss of fizz	Better retention of fizz	Best retention of fizz
Texture & Appearance	Can be grainy or cloudy; thickens over time	Smooth, clear consistency; stable over time	Smooth and consistent; easy mixing
Amylase-Resistance	Not resistant; thins out in saliva	Resistant; viscosity remains stable	Resistant; viscosity remains stable
Preparation	Requires vigorous mixing; can clump	Can clump if not mixed carefully	Easy to mix; less risk of clumping
Taste Impact	Can alter taste and mouthfeel	Generally tasteless	Generally tasteless
Cost	Generally less expensive	Moderate cost; requires less product	Higher convenience cost

Nutritional and Dietary Implications

While thickening Coke is physically possible, its suitability within a healthy nutrition diet, especially for individuals with underlying health conditions, is highly questionable. The key issue lies in the nutritional content, or lack thereof, in cola.

Regular Coke: One standard can of Coca-Cola contains approximately 39 grams of sugar, equivalent to roughly 9-10 teaspoons. This high sugar content provides empty calories with no vitamins, minerals, or fiber. Regular consumption can contribute to metabolic syndrome, diabetes, and weight gain, making it a poor choice for a nutrition-focused diet. For someone with dysphagia, whose intake might already be limited, filling up on sugar-laden, non-nutritious liquid can exacerbate malnutrition.
Diet Coke: Marketed as a zero-sugar, zero-calorie alternative, Diet Coke is sweetened with artificial sweeteners like aspartame. While it avoids the sugar load of regular cola, it still offers no nutritional value. Furthermore, studies have shown conflicting results regarding artificial sweeteners and weight loss, with some research suggesting potential links to increased appetite and metabolic issues. For individuals trying to maintain a healthy diet, particularly those managing health conditions like diabetes, relying on artificially sweetened beverages is not a wise nutritional strategy.

Broader Health Risks of Thickened Fluids

Beyond the specific nutritional issues of cola, patients on a thickened fluid diet face additional risks that a dietitian should monitor. These are primarily related to adherence and physiological effects.

Dehydration: Many studies show that patients often fail to meet their daily fluid requirements when on a thickened liquid diet. This is often due to the unpalatability and unusual mouthfeel of thickened drinks, which can reduce intake. Early satiety, feeling full faster from the thickener, is also a contributing factor.
Gastrointestinal Issues: Reduced fluid intake can lead to constipation. In some cases, certain thickeners have been associated with other gastrointestinal impacts, though these are less common.
Medication Efficacy: Thickeners can potentially slow the dissolution and absorption of oral medications, which can impact their effectiveness. Pharmacists and doctors should be informed if a patient is using thickened liquids to ensure no negative drug interactions occur.

Healthier Alternatives to Thickened Cola

Given the nutritional deficiencies and associated health risks of thickened cola, it is far more beneficial to incorporate healthier, more nutritious beverages into a dysphagia diet.

Thickened Juices: Fruit juices like apple, grape, or cranberry can be thickened, and some brands are even available pre-thickened. For those with texture sensitivity, blending fruit to a smooth puree is another option. While juices contain sugar, they also provide some vitamins and nutrients absent in soda.
Infused Water and Herbal Teas: For a low-calorie, hydrating option with flavor, plain water or herbal teas can be thickened. Adding fruit slices (e.g., lemon, cucumber, mint) to water before thickening can provide a pleasant taste without added sugar or artificial sweeteners.
Thickened Milk or Dairy Alternatives: For those who need extra protein and energy, thickened milk or nutritional supplements like Boost or Ensure can be beneficial. Blended milkshakes with added protein powder or yogurt can provide a caloric boost while being easy to swallow.
Smoothies: Creating a smoothie with blended fruits, yogurt, and a liquid thickener can provide a nutrient-dense, easy-to-swallow drink. For more information on dysphagia management and the IDDSI framework, the International Dysphagia Diet Standardisation Initiative website is an excellent resource.

Conclusion

So, can coke be thickened? Technically yes, using commercial thickeners, particularly gum-based gels, which best manage carbonation and provide stable viscosity. However, from a nutrition diet perspective, it is a poor choice due to its lack of nutrients and high sugar or artificial sweetener content. For individuals with dysphagia, prioritizing nutritious, fortified beverages or fortified alternatives is essential for maintaining proper hydration and nutritional status. All dietary adjustments, including the use of thickened liquids, should be discussed with a healthcare team to ensure safety and meet individual nutritional needs.

Frequently Asked Questions

Gum-based gels, like SimplyThick, are generally considered the best option for thickening carbonated drinks because they are more effective at preserving some of the fizz and result in a clearer, smoother liquid with a more stable consistency.

Yes, thickening agents can alter the taste and mouthfeel of any beverage. While tasteless thickeners like xanthan gum gels are designed to minimize this, the change in texture is often significant and can impact a patient's adherence to the diet.

No, Diet Coke is not a healthy option for a thickened diet. While it contains no sugar or calories, it also has no nutritional value. Relying on artificially sweetened beverages is not a wise nutritional strategy and may have its own health implications.

The primary risk is the lack of nutritional value, particularly with regular Coke's high sugar content and the empty calories in both versions. This can contribute to poor overall nutrition, potentially worsening underlying health conditions.

Starch-based thickeners like cornstarch will cause Coke to lose all carbonation and can lead to an undesirable, cloudy texture. Gelatin is also not suitable for carbonated drinks. Commercial, amylase-resistant, gum-based thickeners are far more reliable and medically safer for dysphagia.

To improve palatability, offer a variety of naturally flavorful alternatives like thickened fruit juices, pureed fruit smoothies, or herbal teas. Ensuring drinks are served at the right temperature can also make a difference.

A dietitian or speech-language pathologist should guide any dietary changes for dysphagia. They can assess swallowing ability, determine the correct thickness level, and advise on nutritionally sound beverage choices to prevent malnutrition, dehydration, and aspiration.