Are there carbohydrates in vapes? Understanding e-liquid ingredients

November 21, 2025 •

4 min read

According to manufacturers and health information, commercial e-liquids do not contain sugars, but rely on other compounds for their taste. This often leads to confusion about the potential for carbohydrates in vapes among health-conscious individuals, especially those on low-carb diets. The answer is complex, as it involves understanding the primary components of e-liquid and how the body processes them through inhalation, which is different from digestion.

Quick Summary

This article explains the core ingredients in e-liquid, such as propylene glycol (PG) and vegetable glycerin (VG), clarifying that while VG is technically a sugar alcohol, it does not function as a source of dietary carbohydrates when vaporized. It details how the body processes these compounds differently through inhalation compared to ingestion, and addresses the minimal caloric intake associated with vaping.

Key Points

No Dietary Carbohydrates: Commercial e-liquids do not contain added sugars or significant dietary carbohydrates that are metabolized by the body in the same way as food.
VG is a Sugar Alcohol: Vegetable glycerin (VG), a key e-liquid ingredient, is a sugar alcohol, but the negligible calories are not absorbed efficiently when inhaled.
Inhalation vs. Digestion: The body processes inhaled vapor differently than it does ingested food, so the minimal calories in vape juice have no significant impact on overall caloric intake.
No Interference with Keto: Since e-liquids lack traditional carbohydrates, vaping does not break ketosis, making it suitable for those on a ketogenic diet.
Nicotine's Indirect Effects: While not a carb, nicotine can increase insulin resistance, a risk factor for diabetes, and should be considered by those managing blood sugar.
Potential for Harmful Byproducts: When heated, e-liquid components like PG and VG can break down into harmful chemicals, highlighting health risks beyond dietary concerns.
Artificial Sweeteners Used: The sweet taste in many vape juices comes from artificial sweeteners like sucralose, not sugar.

What Are the Primary Components of E-Liquid?

E-liquids, also commonly referred to as vape juice, consist of four main ingredients that determine their properties and effects: a base liquid blend of propylene glycol (PG) and vegetable glycerin (VG), flavorings, and optionally nicotine. Each of these components plays a specific role in the vaping experience, from vapor production to flavor intensity.

Propylene Glycol (PG): This is a thin, clear, odorless liquid commonly used in food and pharmaceutical products. In e-liquid, PG is known for carrying flavor and providing a stronger 'throat hit' sensation. While technically an alcohol compound, it does not act as a dietary carbohydrate in the same way that sugars do.
Vegetable Glycerin (VG): Derived from vegetable oils, VG is a thicker, slightly sweet-tasting liquid responsible for producing large, dense vapor clouds. VG is a sugar alcohol and is technically a type of carbohydrate, meaning it has a caloric value if ingested orally. However, the crucial difference lies in how it's consumed.
Flavorings: These are food-grade substances, both natural and artificial, that create the wide variety of available e-liquid flavors. Common sweeteners added to create candy-like flavors are not sugar but artificial substitutes like sucralose and ethyl maltol. Sucralose, in particular, does not vaporize cleanly and can lead to residue on heating coils, known as 'coil gunk'.
Nicotine: A highly addictive substance extracted from tobacco or synthesized. Nicotine has no significant caloric value and does not contribute to carbohydrate intake.

Inhalation vs. Ingestion: Why Calorie Count Differs

The central reason that carbohydrates from VG don't impact your diet in the traditional sense is the method of consumption. When you eat food, your digestive system breaks down the carbohydrates, fats, and proteins to be metabolized for energy. Vaping, however, involves inhaling a heated aerosol.

The American Diabetes Association notes that when VG is consumed orally, it has about 4.32 calories per gram. But when vaporized and inhaled, the body's absorption of these calories is extremely low. The lungs are not a digestive organ, and as a result, the body does not metabolize the compounds in the same way as food. Therefore, the minimal caloric content is considered negligible and doesn't affect your daily intake. For example, the total calories in a full 30ml bottle of e-liquid are roughly comparable to a single celery stalk.

The Relationship Between Vaping, Carbohydrates, and Keto Diets

Many people, particularly those following a ketogenic diet, are concerned about any hidden carbs that could disrupt ketosis. Since e-liquids do not contain traditional sugars and the VG is not absorbed as a dietary carbohydrate, vaping is not considered a source of carbs that would break ketosis. Nicotine itself is also carb-free. This makes vaping a feasible option for individuals on a keto diet. However, it's important to differentiate between actual carb content and indirect health effects.

Indirect Effects of Vaping on Blood Sugar

While the carbs in vapes are not a dietary issue, other components can have an indirect effect on metabolic health, especially for those with diabetes or prediabetes. Studies have shown potential links between nicotine-containing e-cigarette use and insulin resistance. Nicotine can reduce insulin sensitivity, which makes blood glucose control more challenging. Furthermore, some studies suggest a link between vaping and an increased risk of prediabetes. These potential metabolic effects, though not caused by dietary carbs, are an important consideration for anyone managing blood sugar.

Comparison Table: Inhaled VG vs. Digested Sugar


Feature	Vegetable Glycerin (VG) - Inhaled	Sugar - Digested
Carbohydrate Source	Technical sugar alcohol; not a dietary carb via inhalation	Simple or complex carbohydrate
Metabolism	Not metabolized by the digestive system as a carbohydrate.	Broken down by the digestive system for energy.
Caloric Impact	Negligible; minimal absorption through lungs.	Significant; contributes to daily caloric intake.
Insulin Response	Minimal direct impact, but nicotine can indirectly affect insulin sensitivity.	Direct and significant impact, causing blood sugar spikes.
Effect on Ketosis	None; does not interfere with ketosis goals.	Breaks ketosis due to carbohydrate content.
Primary Function in Vape	Produces dense vapor clouds and provides a smoother hit.	N/A (not used in commercial e-liquids).

Potential Health Risks Beyond Carbohydrates

Beyond the carbohydrate question, there are other important health considerations for vapers. The long-term effects of inhaling PG and VG aerosols are not yet fully understood. When heated, these compounds can break down into toxic chemicals like formaldehyde and acetaldehyde, which are known carcinogens. Moreover, flavorings can contain potentially harmful chemicals, and some studies have found heavy metals like lead and nickel from the heating coils in the aerosol. Individuals with sensitivities to PG may also experience side effects like throat irritation or dehydration.

Conclusion

In summary, the question of whether there are carbohydrates in vapes can be answered with a qualified 'no' regarding dietary impact. While vegetable glycerin (VG) is a sugar alcohol and technically a carbohydrate, the calories are not absorbed effectively through inhalation, making their dietary contribution negligible. Commercial e-liquids do not contain added sugar, relying instead on artificial sweeteners for flavor. The more significant health concern for vapers on restricted diets or with blood sugar issues is not the carbohydrates, but the indirect metabolic effects of nicotine and the potential risks from other components found in the aerosol. For those with diabetes, monitoring blood sugar is advised, as nicotine can increase insulin resistance. As with any product involving inhalation, a comprehensive understanding of the ingredients and potential risks is essential for making informed health decisions. For further reading on the broader health implications, resources like the American Lung Association offer valuable insights into the dangers of vaping.(https://www.lung.org/blog/dangerous-vape-ingredients)

Frequently Asked Questions

Vaping is not considered to break a fast for most people, as the caloric and metabolic impact of the minimal calories in e-liquid, especially when inhaled, is negligible. However, some strict fasting protocols may prohibit any substance other than water.

The sweet taste in many vapes comes from artificial sweeteners like sucralose or ethyl maltol, which are added to e-liquid flavorings. These compounds provide sweetness without adding traditional sugar.

While e-liquid has no carbs, nicotine itself can indirectly affect blood sugar by increasing insulin resistance, which can be a concern for individuals with diabetes or prediabetes.

VG is a sugar alcohol but its oral caloric content is minimal and not efficiently absorbed when vaped. For diabetics, the bigger issue is nicotine's effect on insulin sensitivity, not the VG content.

Gaining weight directly from vaping is highly unlikely due to the negligible caloric intake from inhaling e-liquid. However, quitting nicotine may lead to increased appetite, which could cause weight gain.

PG is a thinner liquid that carries flavor and provides a stronger throat hit. VG is a thicker, slightly sweet liquid that produces larger vapor clouds. E-liquids often use a mix of both.

Yes, commercially produced e-liquids generally do not contain added sugar. Instead, they use artificial sweeteners to achieve sweet flavors, as sugar would condense and burn on the heating coil.