47 kcal P 0.91g C 11.8g F 0.15g
🥦 Vegetables and Vegetable Products
Calories in Fennel, bulb
Fennel bulb is not a root but a swollen leaf base, packing anise-flavored essential oils that evolved to repel insects.
27 kcal
What makes fennel so powerful?
Fennel's distinctive licorice aroma comes from anethole, an aromatic compound that also occurs in star anise. While many assume the fennel bulb grows underground like a root vegetable, it is actually a layered, swollen leaf base that sits just above the soil line. Botanically, fennel (Foeniculum vulgare) belongs to the Apiaceae family, making it a close relative of carrots, dill, and parsley. The plant evolved to produce volatile oils like anethole and fenchone as a natural defense mechanism against herbivorous insects, though humans have cultivated and prized these same compounds for millennia. Ancient Greeks and Romans associated fennel with strength and longevity, using it both as a dietary staple and a medicinal aid for digestion. When you slice into a raw fennel bulb, you are breaking open specialized plant cells that release these defensive oils, which is why the scent is strongest immediately after cutting. Cooking the bulb alters the cellular structure and volatilizes some of these oils, which mellows the sharp anise flavor into a sweeter, nuttier profile.
Not a root vegetable
The edible bulb is actually a swollen leaf base that grows above ground, not a subterranean root.
Anethole defense mechanism
Its licorice scent comes from volatile oils evolved specifically to deter insect predators.
Heat transforms flavor
Roasting or braising volatilizes the sharp anise oils, leaving a sweet, nutty taste.
💡 When & how to use it
To maximize both flavor and nutrition, slice the bulb very thin and eat it raw in salads to retain its crisp texture and high vitamin C content. If you prefer cooked fennel, roast the wedges with a little olive oil; the heat breaks down the fibrous cell walls, making the vegetable easier to digest while caramelizing its natural sugars. Store the bulb in the refrigerator crisper drawer tightly wrapped to prevent it from absorbing other flavors and drying out. Save the fronds to use as a fresh, dill-like garnish.
Calories by Serving Size
100g
27 kcal
P 0.92g C 5.49g F 0.14g
200g
54 kcal
P 1.8g C 11g F 0.3g
50g
14 kcal
P 0.5g C 2.7g F 0.1g
Full Nutrition Facts
Per 100g — daily values based on a 2,000 calorie diet
Nutrition Facts
Serving size: 100g
Calories 27
% Daily Value*
Total Fat 0.14g 0%
Sodium 49mg 2%
Total Carbohydrate 5.49g 2%
Dietary Fiber 2.05g 7%
Protein 0.92g 2%
Vitamin C 14.7mg 16%
Calcium 41.3mg 3%
Iron 0mg 0%
Potassium 332mg 7%
* Percent Daily Values are based on a 2,000 calorie diet. Your daily values may be higher or lower depending on your calorie needs.
How does Fennel fit your daily goals?
5 min
Walking to burn 27 kcal
1%
of 2,000 kcal daily goal
0.92g
protein (2% of daily 50g)
74
servings until 2,000 kcal
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Frequently Asked Questions
How many calories are in Fennel, bulb?
Fennel, bulb contains 27 calories per 100g. It is considered a very low-calorie food (under 50 kcal/100g), making it excellent for weight management.
How much protein does Fennel, bulb have?
Fennel, bulb provides 0.92g of protein per 100g, which is 2% of the 50g daily recommended value. It is not a primary protein source.
How many carbs are in Fennel, bulb?
Fennel, bulb contains 5.49g of carbohydrates per 100g . It also provides 2.05g of dietary fiber.
Is Fennel, bulb good for weight loss?
Yes! Fennel, bulb is very low in calories (27 kcal/100g) and can be eaten in generous portions even on a calorie-restricted diet.
How do I track Fennel, bulb calories accurately?
The easiest way to track fennel is with CalRay. Simply snap a photo of your meal and the AI will automatically identify the food and calculate calories and macros based on the estimated portion size — no manual lookup required. You can also search by name and adjust gram weight manually.
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