Health Benefits of Fennel

Medically Reviewed by Kathleen M. Zelman, RD, LD, MPH on November 10, 2022
3 min read

Fennel is a root vegetable in the same family as carrots and celery. It’s a relatively large plant, with branches that can grow up to 7 feet above the ground. 

Fennel is an aromatic vegetable with a sweet taste similar to licorice. Although commonly used in curries and Italian cooking, fennel’s popularity is growing as an ingredient in Western cuisine. 

There are two major varieties of fennel: herb fennel and Florence fennel. Herb fennel is generally used for seeds and to make spices while the bulbs of Florence fennel are often eaten as a vegetable. 

Like many vegetables, fennel is a low-calorie food rich in nutrients. Here are just a few of the many benefits of adding fennel to your diet. 

Improve Digestion

In many parts of the world, it’s common to eat a little bit of fennel after a meal to aid with digestion and relieve gassiness. Fennel has been shown to help with digestion by reducing inflammation in the bowels and decreasing bacteria that cause gassiness. One study also showed that fennel oils could help relieve symptoms of irritable bowel syndrome

Relieve Menstrual Cramps

Menstrual cramps can range in severity from annoying to debilitating. For some people, their cramps are painful enough to interfere with school, work, or other activities. Underlying conditions like endometriosis and uterine fibroids can make menstrual cramps worse. 

For women with painful menstrual cramps, fennel may provide relief. Studies show that the nitrites in fennel improve blood flow, which can help the uterus more efficiently expel the uterine lining and shorten the length of menstruation. 

Other studies show that fennel can reduce the production of oxytocin and prostaglandin, two hormones that contribute to painful periods. One study also showed a significant reduction in menstrual cramps when people took fennel.

Improve Colic

Colic is a common medical condition affecting newborn babies that can cause fussiness and discomfort. Food allergies and intolerances are thought to be a major cause of colic. 

Gripe water—a common, over-the-counter treatment for colic—often contains fennel. Fennel has been proven to help ease colic in about 65% of cases. 

Keep in mind that not all gripe waters have the same ingredients. Check packaging information to see if the gripe water you’re using contains fennel. 

Despite the sweet taste, fennel contains no sugars—making it a good way to add sweetness to meals without spiking your blood sugar.

Fennel is also rich in: 

  • Iron
  • Vitamin A
  • Vitamin C
  • Calcium

Nutrients per Serving

½ cup of sliced fennel contains: 

  • Calories: 13
  • Fat: 0 grams
  • Cholesterol: 0 milligrams
  • Sodium: 23 milligrams
  • Carbohydrates: 3 grams
  • Fiber: 1 gram
  • Sugars: 0 grams
  • Protein: 0.5 gram

Things to Watch Out For

Although fennel eaten in normal amounts is generally safe, some people may need to be cautious about how much they consume. One study showed that breastfeeding mothers who drank two or more liters of fennel tea each day reported signs of pain in their infants.

Fennel can also interact with certain medications, including seizure medications. Check with your doctor before taking fennel supplements or using fennel essential oils, and remember that moderation is key when cooking and eating fennel. 

The bulb is the tastiest part of this root vegetable. To prepare fennel, slice the bulb into strips. You can cook fennel the same way you would cook other root vegetables, such as carrots—by roasting, baking, sautéing, or grilling it.

Fennel has a sweet, earthy flavor, similar to licorice. It pairs well with foods that are a combination of sweet and savory, including curries, pumpkin soups, and apple-stuffed pork chops. 

Some common ways to add fennel into your diet include: 

  • Substitute fennel stalks for celery stalks in recipes for soups or stews.
  • Wrap fennel in tin foil with ham and other root vegetables and cook in the oven until soft.
  • Use sautéed fennel as a bed for roast chicken or pork.
  • Dice fennel and add it to a salad.
  • Roast fennel wedges with salt, pepper, and butter