How many kcal are in 100g of sugar?

November 1, 2025 •

4 min read

According to USDA data, 100 grams of granulated sugar contains approximately 387 kilocalories. This pure carbohydrate source is calorie-dense, providing energy but lacking essential nutrients like protein, fat, and fiber. Understanding how many kcal are in 100g of sugar is crucial for managing your overall caloric intake and making informed dietary choices.

Quick Summary

100g of granulated sugar contains roughly 387 kilocalories, sourced entirely from carbohydrates with no protein, fat, or fiber. Its high energy density means it's important to monitor intake, as excessive consumption can contribute to weight gain and other health issues.

Key Points

387 kcal per 100g: Granulated sugar contains approximately 387 kilocalories for every 100 grams.
Pure Carbohydrate Source: All of sugar's calories come from carbohydrates; it contains no fat, protein, or fiber.
Impact on Weight: The high-calorie density of sugar can easily lead to excessive calorie intake and contribute to weight gain.
Health Risks: High sugar consumption is linked to a higher risk of heart disease, Type 2 diabetes, and fatty liver disease.
Read Labels: Always check the 'Added Sugars' section on nutrition labels to manage intake, as sugar hides under many names.
Consider Alternatives: Low-calorie sweeteners like stevia or allulose offer a way to reduce caloric intake while maintaining sweetness.
Opt for Whole Foods: Prioritize fruits and other whole foods, which provide natural sugars along with fiber and other vital nutrients.
Limit Sugary Drinks: Switching from sodas and juices to water is one of the most effective ways to lower sugar intake.

The Kilocalorie Content of 100g of Sugar

At a fundamental level, 100 grams of granulated sugar, also known as sucrose, provides approximately 387 kilocalories (kcal). This number can vary slightly depending on the exact type of sugar, such as brown or white, but the difference is minimal. A kilocalorie is the scientific unit used to measure energy from food. Since sugar is a simple carbohydrate, it contains about 4 calories per gram. With 100 grams being almost pure carbohydrate, the math is straightforward: 100g x 4 kcal/g = 400 kcal, with the slight deviation in reality coming from trace amounts of moisture and other minerals.

A Deeper Look at Sugar's Nutritional Profile

Beyond just calories, the nutritional profile of 100g of sugar is notable for what it lacks rather than what it provides. Unlike nutrient-dense foods, sugar offers "empty calories". This means it provides energy without supplying the vitamins, minerals, protein, or fiber necessary for a balanced diet. Consuming large amounts can therefore displace more nutritious options and potentially lead to deficiencies over time.

Key nutritional characteristics per 100g of granulated sugar:

Carbohydrates: Almost 100g, consisting primarily of sucrose.
Fats: 0g.
Protein: 0g.
Fiber: 0g.
Vitamins & Minerals: Trace amounts, but not nutritionally significant.

This composition explains why sugar provides a quick energy boost. The body rapidly breaks down simple carbohydrates into glucose for immediate use. This is in stark contrast to complex carbohydrates, which are digested more slowly and offer a sustained release of energy.

The Impact of High Sugar Intake on Health

Regularly consuming excess sugar is a well-documented health risk. The high calorie count in sugar can contribute significantly to overall daily caloric intake, leading to weight gain and obesity if not balanced with physical activity. Overconsumption is linked to numerous chronic conditions:

Heart Disease: High-sugar diets are associated with increased risk factors for heart disease, including high blood pressure, inflammation, and high triglycerides.
Type 2 Diabetes: Excess sugar consumption can lead to insulin resistance, a key precursor to type 2 diabetes.
Fatty Liver Disease: Fructose, a component of table sugar, is processed by the liver. Too much fructose can overload the liver and contribute to non-alcoholic fatty liver disease (NAFLD).
Dental Issues: Bacteria in the mouth feed on sugar and produce acids that erode tooth enamel, leading to cavities and tooth decay.

A Comparison of Sugar and Other Sweeteners

To better understand the calorie density of sugar, it is helpful to compare it to other common sweeteners and sugar alternatives. The table below illustrates the vast differences in caloric content.


Sweetener	Calories per 100g	Notes
Granulated Sugar	~387 kcal	Provides a sharp rise in blood sugar due to pure carbohydrate content.
Brown Sugar	~377 kcal	Slightly less calorie-dense due to moisture and trace minerals from molasses.
Honey	~304 kcal	Contains water and some minerals; a combination of fructose and glucose.
Maple Syrup	~260 kcal	Contains less sugar per gram than granulated sugar because of its water content.
Allulose	~38 kcal	A rare, low-calorie sugar. The body absorbs it but does not metabolize it for energy.
Erythritol	~20 kcal	A sugar alcohol with very few calories, as the body doesn't fully absorb it.
Stevia	0 kcal	A natural, non-caloric sweetener derived from the stevia plant.

How to Reduce Your Sugar Intake

For those looking to reduce their sugar consumption, several strategies can help:

Read Food Labels Carefully: The "Added Sugars" section on a nutrition label clearly indicates how much sugar has been added to the product. Look for hidden sugars under different names, such as sucrose, high-fructose corn syrup, and dextrose.
Choose Whole Foods: Focus on eating whole, unprocessed foods like fruits, vegetables, and lean proteins. These foods provide natural sugars alongside beneficial nutrients like fiber.
Drink Water: Swap sugary beverages like soda, juice, and sweetened tea for water. This is one of the easiest and most effective ways to cut added sugar from your diet.
Use Natural Alternatives for Sweetening: Instead of table sugar, consider using natural, whole food sweeteners like fruit purées or spices like cinnamon. For baking, explore low-calorie alternatives like stevia or monk fruit.
Reduce Portion Sizes: Gradually reduce the amount of sugar you add to coffee, tea, or recipes. Your taste buds will adjust over time, and you will become less reliant on a high level of sweetness.

Conclusion

100 grams of sugar contains a significant amount of energy, roughly 387 kilocalories, but lacks any other nutritional benefit. This makes it a prime example of a food that contributes to calorie intake without providing essential vitamins, minerals, or fiber. For optimal health, it is recommended to limit the consumption of added sugars in favor of whole foods and natural sweeteners. By being mindful of your sugar intake and understanding its caloric impact, you can make healthier choices and manage your diet more effectively.

Frequently Asked Questions

No, brown sugar has a very similar calorie count to white sugar. While brown sugar contains molasses, which adds some trace minerals, its caloric difference per 100g is minimal, approximately 377 kcal compared to 387 kcal for white sugar.

Based on the calculation of 387 kcal per 100g, one teaspoon (approximately 4.2g) of granulated sugar contains about 16 calories.

The World Health Organization (WHO) recommends limiting the intake of free sugars to less than 10% of total daily energy intake, with a further reduction to below 5% suggested for additional health benefits. For a 2,000-calorie diet, this is less than 50g (approx. 12 teaspoons) or ideally less than 25g (approx. 6 teaspoons).

Calories are all units of energy, but calories from sugar are often considered 'empty calories' because they provide energy without accompanying nutrients like vitamins, minerals, or fiber. This makes them less beneficial than calories from whole foods, which contribute to overall nutritional needs.

Excessive sugar intake is a major risk factor for developing Type 2 diabetes, primarily by contributing to weight gain and insulin resistance. However, sugar alone is not the sole cause, as genetic factors, physical activity, and overall diet also play significant roles.

Check the nutrition facts label for "Added Sugars," which is a separate line from "Total Sugars". Also, read the ingredients list for terms like sucrose, dextrose, corn syrup, molasses, or agave, which indicate added sugar.

The body processes natural sugars (found in fruits and milk) and added sugars similarly. However, natural sugars in whole foods come packaged with other beneficial nutrients like fiber, which slows absorption and prevents blood sugar spikes. Added sugars, particularly in processed foods, do not offer this benefit.