Do Runny Eggs Have Less Calories Than Cooked Ones?

December 17, 2025 •

3 min read

Despite what some might assume, the calorie content of an egg remains unchanged by the cooking process. The real question is how many of those calories your body can actually absorb, and the answer might surprise you when comparing runny eggs to fully cooked ones.

Quick Summary

The number of calories in an egg is determined by its size and composition, not the cooking method itself. However, cooking significantly increases the bioavailability of protein, meaning your body absorbs more calories from a cooked egg than a raw or runny one. Any added ingredients like oil or butter, not the cooking time, increase the final caloric count.

Key Points

Total Calories are Fixed: A raw egg and a cooked egg of the same size have the same total number of calories.
Absorption is Higher in Cooked Eggs: Cooking denatures proteins, making about 91% of the protein digestible, versus only 51% in raw eggs.
Digestion Affects Caloric Benefit: Because your body can absorb more nutrients from a cooked egg, you ultimately gain more usable caloric energy from it.
Added Fats are the Calorie Culprit: Any increase in the final calorie count for cooked eggs comes from added butter, oil, or cheese, not the cooking process itself.
Cooking Eliminates Salmonella Risk: Thoroughly cooking eggs is the only way to guarantee the elimination of Salmonella bacteria, making it the safer choice.
Raw Eggs Impede Biotin Absorption: Raw egg whites contain avidin, which binds to biotin and prevents its absorption, a problem eliminated by cooking.
Poached and Boiled Eggs are Lower in Added Calories: These cooking methods use water, resulting in no extra added calories compared to frying.

The Calorie Myth: Raw vs. Cooked Eggs

At its core, an egg contains a set amount of energy, measured in calories, that is dependent on its size. For example, one large egg contains approximately 72 calories. This energy doesn't increase simply by applying heat. The key difference between a raw egg, like one with a runny yolk, and a fully cooked one lies in how efficiently your body can utilize that energy.

Why Digestion Efficiency Matters

When you cook an egg, its protein goes through a process called denaturation. The heat causes the tightly coiled protein molecules to unwind and change shape, making them much easier for your digestive enzymes to break down and absorb. A study published in the Journal of Nutrition found that the human body can absorb 91% of the protein from cooked eggs, but only about 51% from raw eggs.

This difference in absorption means that while a raw or runny egg and a hard-boiled egg contain the same total calories, your body will actually gain more nutritional energy from the cooked one. When you eat a raw egg, a significant portion of its protein and associated calories pass through your system without being fully digested.

The Impact of Added Ingredients

Most people's perception of a difference in calories comes from how eggs are prepared. A poached or soft-boiled egg is cooked in water and doesn't require any added fats, so its final calorie count is essentially the same as the raw egg. However, a fried egg, scrambled eggs, or an omelet cooked in butter, oil, or with added milk and cheese will have a higher calorie count because of the additional ingredients.

Comparison of Egg Cooking Methods


Cooking Method	Added Fat	Calorie Impact	Protein Digestibility	Salmonella Risk
Raw/Runny	None	Same as raw egg, but less is absorbed	Approx. 51% absorbed	Present
Hard-Boiled	None	Same as raw egg, full absorption	Approx. 91% absorbed	Eliminated
Poached	None	Same as raw egg, full absorption	Approx. 91% absorbed	Eliminated
Fried/Scrambled	High	Added calories from butter/oil/etc.	Approx. 91% absorbed	Eliminated

Lists of Factors Affecting Digestion

Beyond cooking, other elements influence the nutritional gain from eggs:

Avidin in raw egg whites: The protein avidin, present in raw egg whites, binds to the vitamin biotin, preventing its absorption. Cooking denatures avidin, allowing biotin to be absorbed normally.
Individual differences: Factors like age and individual metabolism can affect how efficiently nutrients are absorbed. Some people, particularly the elderly, may have less efficient digestive systems.
Heat sensitivity of vitamins: While cooking increases protein bioavailability, it can also decrease some nutrients, like vitamin D, especially with longer cooking times or high heat. The overall nutritional benefit still heavily favors cooked eggs.

Why Cooking is Ultimately Healthier

From a health and safety perspective, cooking eggs thoroughly is the recommended approach. Beyond the increased nutrient absorption, heating eggs to a sufficient temperature (at least 160°F or 71°C) eliminates the risk of bacterial contamination, most notably Salmonella. This is especially important for vulnerable populations like young children, pregnant women, the elderly, and those with compromised immune systems. For the average healthy adult, the risk is small but not zero. Consuming certified pasteurized eggs is the safest way to enjoy eggs in their runny or raw state.

Conclusion

In summary, the notion that runny eggs contain fewer calories is a misconception. The total number of calories in an egg is fixed. The real difference is that cooking an egg increases the bioavailability of its protein, meaning your body can absorb and utilize significantly more of its caloric energy. If you're looking to gain the maximum nutritional benefit from an egg and ensure food safety, cooking it thoroughly is the most effective method, especially for its protein content. For those concerned about calorie intake, the primary variable to consider is the addition of high-fat ingredients like butter or oil, not the runniness of the yolk. You can enjoy your eggs in many forms while being mindful of these factors to best suit your dietary goals.

For more detailed information on nutrient absorption and bioavailability, you can read more on the topic from sources like the National Institutes of Health.

Frequently Asked Questions

Eating runny yolks carries a risk of Salmonella bacteria, which can cause food poisoning. While the risk is low, it is not zero, and the USDA recommends cooking eggs until both the white and yolk are firm.

Cooking eggs makes the protein more digestible through a process called denaturation. This allows your body to absorb more of the protein and its associated caloric energy, resulting in a higher usable calorie count.

Yes, cooking can cause a reduction in some vitamins, like Vitamin A and D, and antioxidants, especially with high heat and long cooking times. However, eggs remain a very nutrient-dense food even when cooked.

Frying eggs adds calories because of the oil, butter, or other fats used in the pan. A plain poached or boiled egg has the same calories as a raw egg, while a fried egg will be higher.

Poaching or soft-boiling are considered among the most nutrient-efficient methods, as they require no added fats and use lower cooking times, preserving more of the egg's heat-sensitive nutrients while increasing protein absorption.

No, the shell color of an egg is determined by the chicken's breed and has no impact on its nutritional content or caloric value.

Avidin, a protein in raw egg whites, binds to the vitamin biotin, which prevents the body from absorbing it. Cooking destroys avidin's ability to bind with biotin, allowing for proper absorption.