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Fennel’s characteristic taste comes from its essential oils

Fennel

Foeniculum vulgare Umbelliferae

Fennel seeds are prime digestive remedies used also for chest infections and for a wide range of women’s health problems.

  • How does it feel?

    Pick up a few fennel seeds from any spice jar and chew them (these will be sweet fennel). You will notice the gradually strengthening licorice-like, almost fruity sweetness, aromatic and slightly spicy tastes, with just a hint of bitterness at the end and a surprising cooling follow-through. Otherwise a very clean effect with no astringency or acidity at all.

  • What can I use it for?

    Given in the form of a homemade tea or infusion, fennel is a useful standby for indigestion and colicky and gassy symptoms in the abdomen, well suited for both children and adults.

    Stronger doses are good for bronchitis and catarrhal conditions, in which excess mucus is produced in the airways.

    In traditional medicine around the world, fennel was classified as heating and drying (a gentle version of the hot spices) and was indicated where the body was fighting ‘cold’ conditions. Such conditions might include symptoms of heavy mucus production and digestive problems, especially linked with low energies.

  • Into the heart of Fennel

    Fennel’s qualities were understood as usual from the characteristic taste which comes from its essential oils. These relax smooth muscle and relieve lower abdominal spasms and bloating in the digestive tract, known as a ‘carminative’ effect. Although a ‘heating’ herb, it benefits digestion without aggravating inflammation.

    Fennel is also an effective expectorant within the respiratory system, encouraging the release of stuck mucous and catarrh. Fennel is particularly supportive to the female reproductive system, encouraging efficient menstruation and reducing the painful and spasmodic symptoms of dysmenorrhea. Its anti-spasmodic activity also extends to muscular spasms and pain.

    For breastfeeding mothers, fennel will also promote efficient lactation.

  • Traditional uses

    The ancient Greek hero Prometheus was said to have carried the fire he stole from the gods (ie the source of human special powers) in a fennel stalk and the plant has long had an important place in European life. It is a well-known culinary herb or vegetable from ancient Roman and Egyptian times that has for as long been regarded as a valuable warming ‘carminative’ (colic and gas reducing) and aromatic digestive; as the English herbalist John Parkinson put it in 1640:  “which being sweet and somewhat hot and comforting the stomach, helpeth to digest the crude flegmatick quality of fish and other viscous meats”. It was a common ingredient in ‘gripe water’ and other remedies for infant colic. It was widely used by women to increase breast milk and given also to increase milk flow in livestock.

    It has long been used for improving appetite, especially during convalescence, and a respiratory remedy and expectorant for coughs and a range of other respiratory conditions. The seeds were applied in nausea, hiccups, shortness of breath, and wheezing. In communist China, “barefoot doctors” used very large doses of fennel to treat acute cramping and abdominal pain, and modern research backs this up. Topically, it found use in Europe and Asia for eye complaints, including conjunctivitis, inflamed eyelids, and as a general “cleanser” to improve vision.

  • What practitioners say

    Digestion: Fennel will relieve digestive discomfort such as flatulence, cramps, nausea and a low appetite or metabolism. It relaxes the smooth muscles and is a specific herb for lower abdominal pain from lower bowel tension. Fennel water is also used for colic in babies.

    Fever management: Fennel is useful when the body’s capacity to maintain a healing fever might be flagging and needed ‘heating’ support. In this context, fennel would be considered particularly applicable when the source of the fever was digestive or respiratory.

    Eye affections: Fennel is a great ingredient in eye baths for conjunctivitis, styes and other surface problems. Eyebaths are made by boiling the seeds in water and the decoction needs to be kept sterile.

    Urinary: Helpful in cystitis, difficult urination, burning and dark yellow urine, cloudy urine.

    Nervous: Indicated in nervous tension created by muscular spasms and contraction. All spasms are relieved with fennel, especially in the digestive tract, lungs and womb. Its nourishing effects means that it tonifies the brain and nervous system.

    Respiratory: Used in congestive or productive coughs.

    Women’s health: Fennel can increase the flow of breast milk in breastfeeding mothers. It can also be used in menstrual difficulties that obstruct the lower abdomen influencing pain, cramps and a dragging sensation.

    It is a specific herb for inguinal hernias and lower abdominal pain.

  • Research

    Fennel has increasingly shown to be a useful women’s remedy. It is an effective and safe treatment to reduce menstrual pain and duration, premenstrual syndrome, menopausal symptoms in postmenopausal women, and was also found effective in menopausal women with depression and anxiety disorders. In a separate study fennel vaginal cream was found to be an effective means of easing sexual activity in postmenopausal women.

    There is some evidence that fennel does relieve colic in children and infants.

  • Did you know?

    Many people associate fennel with the bulbous base of the plant that is cooked as a vegetable. This is a modified variety that has been created through years of careful selection and breeding. Known as Florence fennel (or Foeniculum vulgare var. azoricum), this variety is much shorter in height than the sweet and bitter varieties that are used medicinally.

Additional information

  • Safety

    Fennel appears to be an extremely safe herb when consumed in recommended doses. Regulatory authorities have generally played down concerns about the effects of constituents estragole and anethole. There are rare cases of contact allergy.

  • Dosage

    From 500mg right up to 9g/day of dried fennel seeds depending on effect required

  • Constituents

    The chemical composition differs between the two varieties. The sweetness of fennel is due to the presence of trans-anethole and estragole. Sweet varieties of fennel taste sweeter than the bitter varieties because they contain more trans-anethole and less bitter fenchone.

    Bitter fennel:

    • essential oil (>4%) containing >60% trans-anethole, <15% fenchone, <5% estragole

    Sweet fennel:

    • essential oil (>2%) containing >80% trans-anethole, <7.5% fenchone, <10% estragole

    Both fennels also contain:

    • fixed oil
    • flavonoids
    • plant sterols, including beta-sitosterol.
  • Traditional energetics

    • Rasa (taste): Sweet, pungent, bitter.
    • Virya (action): Slightly Heating.
    • Vipaka (post-digestive effect): Sweet.
    • Guna (quality): Light, dry.
    • Dosha effect: tridoshic: strengthens all the doshas
    • Dhatu (tissue): Plasma, blood, muscles, nerve.
    • Srotas (channels): Digestive, respiratory, nervous, urinary, reproductive, lactation.
  • Recipe

    Digestive detox tea

    This detoxifying blend of tasty seeds and roots will help to regulate digestion, banish sluggishness and cleanse the blood.

    Ingredients:

    • Aniseed 4g
    • Fennel seed 4g
    • Cardamom pod 3g
    • Dandelion root 2g
    • Licorice root 1g
    • Celery seed 1g
    • Lemon a twist per cup

    This will serve 2 cups detoxifying tea with a citrus twist.

    Method:

    • Put all of the ingredients in a pot (except for the lemon juice).
    • Add 500ml/18fl oz freshly boiled filtered water.
    • Leave to steep for 10–15 minutes, then strain.
    • Enjoy with a twist of lemon in each cup.

    I love my liver tea

    Our liver takes the brunt of the grunt work for metabolising wastes, so use this tea when you feel sluggish, your digestion is poor or you feel that you need a detox.

    Ingredients:

    • Dandelion root 4g
    • Schisandra berries 3g
    • Dandelion leaf 2g
    • Fennel seed 2g
    • Turmeric root powder 1g
    • Rosemary leaf 1g
    • Licorice root 1g

    This will serve 2–3 cups of liver-loving tea.

    Method:

    • Put all of the ingredients in a pot. Add 500ml/18fl oz freshly boiled filtered water.
    • Leave to steep for 10–15 minutes, then strain.

    Let me glow tea

    This delicious recipe is a healing blend of chlorophyll-rich herbs that purify the blood, soothe the liver and cleanse the skin, helping you glow from the inside out. Good for anyone with pimples, acne or other skin blemishes.

    Ingredients:

    • Nettle leaf 3g
    • Fennel seed 2g
    • Peppermint leaf 2g
    • Dandelion root 2g
    • Burdock root 2g
    • Red clover 2g
    • Turmeric root powder 1g
    • Licorice root 1g
    • Lemon juice a twist per cup

    This will serve 2 cups of beautifying tea.

    Method:

    • Put all of the ingredients in a pot (except the lemon). Add 500ml/18fl oz freshly boiled filtered water.
    • Leave to steep for 10–15 minutes, then strain and add the lemon.

    Recipes from Cleanse, Nurture, Restore by Sebastian Pole

Aromatic
An ‘aromatic’ remedy, high in volatile essential oils, was most often associated with calming and sometimes ‘warming’ the digestion. Most kitchen spices and herbs have this quality: they were used both as flavouring and to ease the digestion of sometimes challenging pre-industrial foods. Many aromatics are classed as ‘carminatives’ and are used to reduce colic, bloating and agitated digestion. They also often feature in respiratory remedies for colds, chest and other airway infections. They are also classic calming inhalants and massage oils, and are the basis of aromatherapy for their mental benefits.
Astringent taste
The puckering taste you get with many plants (the most familiar is black tea after being stewed too long, or some red wines) is produced by complex polyphenols such as tannins. Tannins are used in concentrated form (eg from oak bark) to make leather from animal skins. The process of ‘tanning’ involves the coagulation of relatively fluid proteins in living tissues into tight clotted fibres (similar to the process of boiling an egg). Tannins in effect turn exposed surfaces on the body into leather. In the case of the lining of mouth and upper digestive tract this is only temporary as new mucosa are replenished, but in the meantime can calm inflamed or irritated surfaces. In the case of open wounds tannins can be a life-saver – when strong (as in the bark of broadleaved trees) they can seal a damaged surface. One group of tannins, the reddish-brown ‘condensed tannins’ are procyanidins, which can reduce inflammation and oxidative damage.
Bitter
Bitters are a very complex group of phytochemicals that stimulate the bitter receptors in the mouth. They were some of the most valuable remedies in ancient medicine. They were experienced as stimulating appetite and switching on a wide range of key digestive functions, including increasing bile clearance from the liver (as bile is a key factor in bowel health this can be translated into improving bowel functions and the microbiome). Many of these reputations are being supported by new research on the role of bitter receptors in the mouth and elsewhere round the body. Bitters were also seen as ‘cooling’ reducing the intensity of some fevers and inflammatory diseases.
Blue-purple colouring
Any fruits with a blue-purple colouring contain high levels of the polyphenols known as anthocyanins. These work 1) on the walls of small blood vessels, helping to maintain capillary structure to reduce a key stage in inflammation, and improving the microcirculation to the tissues; 2) to improve retinal function and vision; 3) to support connective tissue repair around the body.
Cooling
Traditional ‘cold’ or cooling’ remedies often contain bitter phytonutrients such a iridoids (gentian), sesiquterpenes (chamomile), anthraquinones (rhubarb root), mucilages (marshmallow), some alkaloids and flavonoids. They tend to influence the digestive system, liver and kidneys. Cooling herbs do just that; they diffuse, drain and clear heat from areas of inflammation, redness and irritation. Sweet, bitter and astringent herbs tend to be cooling.
Hot
Traditional ‘hot’ or ‘heating’ remedies, often containing spice ingredients like capsaicin, the gingerols (ginger), piperine (black or long pepper), curcumin (turmeric) or the sulfurous isothiocyanates from mustard, horseradich or wasabi, generate warmth when taken. In modern times this might translate as thermogenic and circulatory stimulant effects. There is evidence of improved tissue blood flow with such remedies: this would lead to a reduction in build-up of metabolites and tissue damage. Heating remedies were used to counter the impact of cold, reducing any symptoms made worse in the cold. .
Mucilaginous
Mucilages are complex carbohydrate based plant constituents with a slimy or ‘unctuous’ feel especially when chewed or macerated in water. Their effect is due simply to their physical coating exposed surfaces. From prehistory they were most often used as wound remedies for their soothing and healing effects on damaged tissues. Nowadays they are used more for these effects on the digestive lining, from the throat to the stomach, where they can relieve irritation and inflammation such as pharyngitis and gastritis. Some of the prominent mucilaginous remedies like slippery elm, aloe vera and the seaweeds can be used as physical buffers to reduce the harm and pain caused by reflux of excess stomach acid. Mucilages are also widely used to reduce dry coughing. Here the effect seems to be by reflex through embryonic nerve connections: reduced signals from the upper digestive wall appear to translate as reduced activity of airway muscles and increased activity of airway mucus cells. Some seed mucilages, such as in psyllium seed, flaxseed (linseed) or guar bean survive digestion to provide bulking laxative effects in the bowel. These can also reduce rate of absorption of sugar and cholesterol. .
New-mown hay aroma
The familiar country odour of haymaking, of drying grass and other plants, is largely produced by coumarins (originally isolated from tonka beans – in French coumarou) and widely used in perfumery. They are chemically categorised as benzopyrone lactones and are important phytochemicals, with strong antioxidant activity in the laboratory and likely effects in modulating inflammation. They were most often associated with the calming effect linked to their use in stuffing mattresses and pillows and plants, high In coumarins were commonly used for these properties.
Resinous
Resins are most familiar as tacky discharges from pine trees (and as the substance in amber, and rosin for violin bows). They were most valued however as the basis of ancient commodities like frankincense and myrrh (two of the three gifts of the Three Wise Men to the baby Jesus) and getting access to their source was one benefit to Solomon for marrying the Queen of Sheba (now Ethiopia). Resins were the original antiseptic remedies, ground and applied as powders or pastes to wounds or inflamed tissues, and were also used for mummification. With alcohol distillation it was found that they could be dissolved in 90% alcohol and in this form they remain a most powerful mouthwash and gargle, for infected sore throats and gum disease. They never attracted much early research interest because they permanently coat expensive glassware! For use in the mouth, gums and throat hey are best combined with concentrated licorice extracts to keep the resins in suspension and add extra soothing properties. It appears that they work both as local antiseptics and by stimulating white blood cell activity under the mucosal surface. They feel extremely effective!
Salty
The salty flavour is immediately distinctive. A grain dropped onto the tongue is instantly moistening and a sprinkle on food enkindles digestion. This easily recognisable flavour has its receptors right at the front of the tongue. The salty flavor creates moisture and heat, a sinking and heavy effect which is very grounding for the nervous system and encourages stability. People who are solid and reliable become known as ‘the salt of the earth'.
Sharpness
The sharp taste of some fruits, and almost all unripe fruits, as well as vinegar and fermented foods, is produced by weak acids (the taste is generated by H+ ions from acids stimulating the sour taste buds). Sour taste buds are hard-wired to generate immediate reflex responses elsewhere in the body. Anyone who likes the refreshing taste of lemon or other citrus in the morning will know that one reflex effect is increased saliva production. Other effects are subjective rather than confirmed by research but there is a consistent view that they include increased digestive activity and contraction of the gallbladder.
Sweet
In the days when most people never tasted sugar, ‘sweetness’ was associated with the taste of basic foods: that of cooked vegetables, cereals and meat. In other words sweet was the quality of nourishment, and ‘tonic’ remedies. Describing a remedy as sweet generally led to that remedy being used in convalescence or recovery from illness. Interestingly, the plant constituents most often found in classic tonics like licorice, ginseng are plant steroids including saponins, which also have a sweet taste.

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