Why are chestnuts so low in calories?

November 26, 2025 •

3 min read

Unlike typical tree nuts that are high in fat, chestnuts have a distinct nutritional makeup that sets them apart. This unique profile is the key factor in explaining why are chestnuts so low in calories, making them an excellent choice for a nutritious, lower-energy snack.

Quick Summary

Chestnuts are low in calories primarily due to their low fat and high water content, unlike most nuts that are rich in fats. Their caloric energy comes mainly from complex carbohydrates, resulting in a significantly lower overall calorie count per serving.

Key Points

Low Fat Content: Chestnuts contain a significantly lower amount of fat compared to other common nuts, which is the primary reason for their low-calorie count.
High Water Content: The high moisture level of fresh chestnuts effectively dilutes their caloric density, further reducing the number of calories per serving.
Carbohydrate-Rich: Most of a chestnut's energy comes from complex carbohydrates and starch, which provide fewer calories per gram than fat.
High in Fiber: Chestnuts are a good source of fiber, which promotes satiety and aids in digestion, supporting overall weight management.
Distinct Nut Profile: Nutritionally, chestnuts behave more like a grain or fruit than a nut, which explains their unusual low-fat, high-carb composition.
Provides Sustained Energy: The complex carbohydrates in chestnuts offer a steady supply of energy, avoiding the blood sugar spikes associated with simple sugars.

The Surprising Nutritional Profile of Chestnuts

Chestnuts stand out in the world of nuts because their nutritional composition more closely resembles a grain than a typical nut. While almonds, walnuts, and cashews are celebrated for their healthy fats, chestnuts are characterized by their high water content and lower fat content. This fundamental difference in macronutrient balance is the primary reason why they possess a lower caloric density.

The Macronutrient Breakdown

To understand why chestnuts have a lower calorie count, one must look at the caloric value of different macronutrients. Fat provides about 9 calories per gram, whereas carbohydrates and protein each provide about 4 calories per gram. Because chestnuts contain very little fat, their total calorie count is dramatically reduced compared to fat-rich nuts. The bulk of a chestnut's energy comes from its complex carbohydrates, which provides slower, more sustained energy without the high-calorie load of fats.

Low in fat: A one-ounce serving of raw, peeled chestnuts contains only about 0.35 grams of fat, compared to 14 grams in a similar serving of almonds. This low fat content is the most significant contributor to their lower overall caloric value.
High in water: Fresh chestnuts have a moisture content of around 50%, which further dilutes their caloric density. Other nuts are significantly drier, concentrating their fats and boosting their calorie count per gram.
Carbohydrate-rich: The majority of a chestnut's calories come from carbohydrates, specifically starch. This makes their nutritional profile similar to brown rice or sweet potatoes, providing a good source of sustained energy.
Fiber content: Chestnuts are also a good source of dietary fiber, which aids in digestion and contributes to a feeling of fullness, or satiety. This can help with weight management by reducing overall food intake.

Comparing Chestnuts to Other Popular Nuts

To truly appreciate the low-calorie nature of chestnuts, comparing their nutritional values to other common nuts is revealing. The following table showcases the stark difference in calories and macronutrient composition per one-ounce (28.35 gram) portion.


Nut Type	Calories	Fat (g)	Protein (g)	Carbs (g)	Key Differentiator
Chestnuts (Raw)	56	0.35	0.46	12.52	High in carbs and low in fat
Almonds	160	14	6	6	High in healthy fats
Walnuts	185	18.5	4.3	3.9	Very high in fat
Pistachios	156	13	6	8	High in fat and protein
Cashews	157	12	5	9	High in fat and protein

Health Benefits Beyond Low Calories

The benefits of chestnuts extend beyond their low-calorie and fat content. They are packed with essential nutrients that contribute to overall well-being.

Rich in antioxidants: Chestnuts are a source of antioxidants like gallic acid and ellagic acid, which help protect the body from oxidative stress.
Source of Vitamin C: Unlike most nuts, chestnuts are a unique and valuable source of vitamin C.
Heart health: The presence of essential fatty acids, magnesium, and potassium supports cardiovascular health.
Gluten-free: Chestnuts and chestnut flour are naturally gluten-free, making them a safe and healthy option for those with celiac disease or gluten sensitivity.

Conclusion

The answer to why chestnuts are so low in calories lies in their fundamental nutritional structure. By trading high-density fats for lower-density complex carbohydrates and a significant amount of water, chestnuts offer a unique, lower-calorie alternative in the nut family. Their low-fat, high-water content, and carbohydrate-rich makeup provide sustained energy and a host of other health benefits, cementing their status as a valuable and nutritious food choice. For further reading, an authoritative source on chestnut nutrition is available through the United States Department of Agriculture (USDA) nutrient database.

Incorporating Chestnuts into Your Diet

Including chestnuts in your meals can be a delicious way to enjoy their health benefits. They can be roasted, boiled, or puréed into soups. Chestnut flour is also a great gluten-free option for baking. Their sweet, earthy flavor works well in both savory and sweet dishes. Due to their perishability, fresh chestnuts should be stored properly in a cool, dark place or refrigerated.

Frequently Asked Questions

Chestnuts are low in calories primarily because they are much lower in fat and higher in water and complex carbohydrates compared to other nuts.

In a one-ounce serving, raw chestnuts have approximately 56 calories, while almonds contain around 160 calories, showcasing a significant caloric difference due to their varying fat content.

Yes, because the majority of a chestnut's calories come from complex carbohydrates, they provide a slower, more sustained release of energy compared to fat-heavy snacks.

While roasting can cause some moisture loss, chestnuts remain relatively low in calories compared to other nuts. The primary nutritional profile of low fat and high carbs holds true even after cooking.

Besides being low in calories, chestnuts are a good source of fiber, antioxidants, and a unique source of vitamin C among nuts. They are also naturally gluten-free.

Yes, the high water content of fresh chestnuts, around 50%, contributes to their lower caloric density by adding weight without adding extra calories.

No, 'horse chestnuts' are from a different genus (Aesculus), are mildly toxic, and should not be consumed. Only sweet, edible chestnuts from the Castanea genus are safe to eat.