Do burnt marshmallows have less calories?

December 21, 2025 •

3 min read

Food scientists confirm that burning food does not substantially change its caloric content. For this reason, the popular notion that burnt marshmallows have less calories is a common myth that is easily debunked by a basic understanding of food chemistry. While a small amount of mass is lost through combustion, the total energy reduction is negligible.

Quick Summary

Burning a marshmallow slightly lowers its calorie count by reducing a minuscule amount of mass through combustion, but the effect is too small to be dietarily significant. Most of the sugar's energy remains, repackaged into new chemical compounds, not eliminated entirely.

Key Points

Negligible Calorie Reduction: Burning a marshmallow does not significantly reduce its caloric content, as the energy is released, not removed, and only a tiny portion of the sugar is affected.
Combustion vs. Elimination: Calories are a unit of energy. Burning a substance is the process of releasing that energy, not magically making it disappear.
Caramelization and Maillard Reaction: The browning process is caused by chemical reactions that alter the sugar and proteins but retain most of the inherent energy.
Charred Outer Layer: Only the outermost layer turns into inedible carbon when charred, leaving the inner, sugary core mostly intact.
Potential Carcinogens: Charring food, especially sugar, can create potentially harmful compounds like polycyclic aromatic hydrocarbons (PAHs).
Misguided Dieting Tactic: Trying to burn calories off food is an ineffective and scientifically incorrect dieting strategy.

The Surprising Truth About Burnt Marshmallows and Calories

Many people believe that charring a marshmallow over a fire somehow burns away the excess sugar and, by extension, the calories. However, this is a profound misconception rooted in a misunderstanding of how energy is stored in food. When you burn a marshmallow, you are indeed causing a chemical reaction, but you are not incinerating all of its caloric content. Instead, the heat triggers complex chemical changes that transform the sugars, rather than eliminating them.

The Science of Marshmallow Browning: Caramelization vs. Maillard Reaction

What you see happening to a marshmallow over a fire is a combination of two distinct chemical processes: caramelization and the Maillard reaction.

Caramelization: This is the process of sugar molecules breaking down and rearranging when heated to high temperatures (above 320°F / 160°C). It involves only sugars and water, creating the classic nutty and sweet 'caramel' flavor and brown color.
Maillard Reaction: This reaction is the interaction between sugars and amino acids (the building blocks of protein), which happens at lower temperatures (around 285–300°F / 140–150°C). This is responsible for the complex, savory flavors found in seared steaks, toasted bread, and also adds to the flavor of a perfectly golden-brown marshmallow.

Both reactions transform the sugars but don't eliminate their caloric energy. When the sugar completely burns, it converts to carbon dioxide and water, releasing its energy as heat and light. This means the energy isn't gone; it's just been released from the food's structure.

Why the Calorie Count Stays (Mostly) the Same

When you torch a marshmallow to a blackened crisp, you are causing a more intense, uncontrolled combustion. The outside of the marshmallow turns into carbon, which has no caloric value for humans. However, the amount of carbonized material is extremely small relative to the marshmallow's total mass. Most of the inside remains soft and sugary, completely unaffected by the surface charring. The total caloric difference between a perfectly toasted marshmallow and a completely burnt one is so minimal that it is statistically insignificant for dieting purposes. If you were to incinerate a marshmallow completely, you would release all its energy, leaving behind only ash, but you wouldn't be eating it.

Potential Health Risks of Charred Food

While burning your marshmallow won't help you lose weight, it can create potentially harmful compounds. The intense heat of high-temperature cooking and burning, especially with high-sugar foods, can form chemicals such as polycyclic aromatic hydrocarbons (PAHs). While the amount of carcinogens in a single burnt marshmallow is minimal, some evidence suggests that regular consumption of charred foods might carry risks.

Calorie Comparison: Raw vs. Burnt Marshmallow

To put the caloric effect into perspective, here's a quick comparison. The calories per gram will shift slightly, but the change is insignificant.


Marshmallow State	Approximate Total Calories	Caloric Change from Raw	Notes
Raw	23 calories	N/A	Based on an average 7.2g marshmallow.
Lightly Toasted	~22.5 calories	Minimal	Loss of a very small amount of moisture and trace sugar during toasting.
Severely Burnt (Charred)	~21.5 calories	Negligible	While some carbon is formed, most of the inner sugar remains intact.
Fully Incinerated	0 calories	All	All energy released; inedible.

The Final Verdict on Burnt Marshmallow Calories

The practice of burning marshmallows to reduce calories is based on flawed logic. The process of burning food releases, rather than eliminates, its stored energy. Any mass lost during charring is too small to have a meaningful dietary impact. The focus for a truly healthier option should be on portion control and moderation, rather than trying to manipulate the cooking process. For health-conscious individuals, enjoying one perfectly golden-brown marshmallow in moderation is a far more satisfying and equally guilt-free alternative to a charred one.

Conclusion

While the crisp, caramelized crust of a toasted marshmallow is a delicious treat, the idea that a burnt marshmallow is a healthier, lower-calorie version is simply false. The caloric content remains largely the same, with any minuscule loss being irrelevant from a dietary perspective. For a better option, consider making your campfire dessert a small part of a balanced diet, and enjoy the taste without the need to excessively burn it. You can learn more about food science and nutrition from authoritative sources like the Institute of Food Technologists.

Frequently Asked Questions

No, it is not healthier to eat a burnt marshmallow. The intense charring can create potentially carcinogenic compounds, and the caloric reduction is too small to be meaningful.

The calorie count of a burnt marshmallow is only negligibly lower than an unburnt one. A standard 7.2g marshmallow has about 23 calories, and a burnt one would have a fraction of a calorie less, making the difference insignificant.

When a marshmallow is burnt, the sugars undergo complex chemical changes, including caramelization. With intense heat, combustion occurs, converting some sugar into carbon dioxide, water vapor, and a black carbon residue.

Toasting a marshmallow involves chemical reactions that transform the sugars into new compounds, but it does not substantially reduce the overall sugar content. Only a very small amount is combusted into gas.

The black char is essentially carbon. High-heat charring can produce PAHs, which are known carcinogens. While a small amount is unlikely to cause immediate harm, it's generally best to avoid consuming heavily charred food.

Caramelizing is a controlled, heat-induced breakdown of sugar that creates a desirable golden-brown color and flavor. Burning is uncontrolled, high-temperature combustion that results in black char and a bitter taste.

The misconception likely stems from the idea that since something was burned away, it must have less energy. It's a misunderstanding of the thermodynamics of combustion versus the nutritional reality.