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In A Nutshell – Milk Thistle – Silybum marianum
by Jill Rosemary Davies
Milk Thistle was used as a premier food and medicinally throughout Europe for over 2,000 years, and up to the middle of the 18th century. The ancient Greeks wrote of its medicinal properties and Roman legionnaires carried the seeds and plants with them to provide food and medicine. Its rightful return to favour as an important and effective food and medicine for liver and kidney support and many other ailments is not surprising. Milk Thistle is a very useful herb to help counteract modern food excesses and, very importantly, for environmental toxins, which are frequently unavoidable.
Exploring Milk Thistle
A history of healing
Milk Thistle in action
Energy and emotion
Growing, harvesting, and processing
Preparations for internal use
tablets and capsules
Preparations for external use
Castor oil pack
Natural medicine for everyone
How Milk Thistle works
The Latin name for Milk Thistle is Carduus marianus, but it is also known as Silybum marianum. For this book the more modern ‘Silybum’ will be used. Silybum comes from the names of the active components, e.g. silibinin.
At one time, Milk Thistle was eagerly sought after as a healing herb. Now, after centuries of neglect, the current interest in herbal medicine and the herb’s particular chemistry have contributed to its comeback as an important and effective remedy for liver disease.
The healing species
Milk Thistle grows as an erect, branching annual or biennial and can reach 2–2.5 m (6½ – 8 ft) in height. Although all parts of the herb are considered to be therapeutic, and used as a food source, it is the seeds that are the most powerful medicinally.
The plant has a rosette of stiff basal leaves lying close to the ground in spring. These leaves are large and prickly, oblong, glossy, and scalloped, varying from dark to light bluish-green. They have distinctive milky-white veins and markings (hence 'Milk Thistle'). The erect, grooved main stem terminates in a stunning solitary, thistle-like flower, 4–8 cm (1½–3 in) across. Each plant has up to four stems, depending upon growing conditions. The violet to purple flowers consist of many tubular florets, with out-curved, needle-shaped, spiny, small leaves at the base. The flowering season can depend on the climate but is typically May to June even in cooler parts of Europe, the US, and Australia; and late summer in cooler climates such as Britain. After flowering, the seed head and creamy-white, fluffy thistledown develops. These carry the large, loose, dark brown ripened seeds which distribute themselves via the wind.
Milk Thistle as food
At one time, Milk Thistle was cultivated extensively as a food plant. Charles Bryant, an 18th century herbalist, wrote in his book Flora Diaetetica, 'The young shoots in the spring, cut close to the root with part of the stalk on [ ... ] surpass the finest cabbage.' Others recommended that the young leaves, stripped of their prickles, could be boiled or blanched as a winter salad. The young stalks, peeled and soaked to remove the bitterness, are nutritious and similar to rhubarb. The Italians are fond of them in spring, when tender stems are eaten raw; and in summer, when mature stems are steamed. The bracts around the flower cluster can be served like globe artichokes; and Arabs consider the leaves to be a delicacy. The root is often dug up after the seeds have been harvested to use as a 'bitter' root vegetable.
Herb or weed
Originally a native of central and southern Europe, Milk Thistle grows well throughout the world in the dry, rocky or stony, thin soils of wasteland, fields and roadsides.
Farmers once considered thistles (crushed to de-prickle them) to be an excellent food for horses and cattle and these are still used by those with a few animals for home rearing and eating. However, in managed farmlands, the Milk Thistle is considered to be a sign of poor husbandry and a threat to other farmers’ land. Early in the 20th century, a bill was passed in the British parliament to enforce the destruction of thistles and other weeds. Similar laws were passed in Australia, Canada, and the United States.
Thistles form a tapestry of colour and texture in the countryside and many of them provide a source of nectar for some of the rarer butterflies. But this elegant and architecturally pleasing plant has fast become a favourite in gardens too, and hopefully this will lead to Milk Thistle reasserting itself in those countries where it has become something of a rarity. However, in countries with sunnier climates such as Spain and Greece, the hardy Milk Thistle can often be found pushing its way up through tarmac and concrete and colonising infrequently used roads.
Botanical family: Compositae (the Daisy family), a family containing a host of medicinal plants including Echinacea, Dandelion, Chamomile, Artichoke, and Cardoon. (The Compositae family is also sometimes referred to as Asteraceae.)
Species: Milk Thistle (Silybum marianum) and other thistle species figure in ancient medical writings. Artichoke (Cynara scolymus) and Cardoon (Cynara cardunculus), which are somewhat similar in appearance, botanical description and medicinal use to Milk Thistle, are also frequently used to aid the gallbladder, liver and kidneys.
Name confusion: Both Milk Thistle and Blessed Thistle (Cnicus benedictus) are known colloquially in some countries as the Holy Thistle. Although frequently interchangeable and sharing many of the same properties, they should not be confused for therapeutic purposes.
Exploring Milk Thistle
Milk Thistle was probably introduced into Britain by the Romans. The medieval herbalist, Gerard, reported that it 'groweth upon waste and common places by high waies, and by dunghills and almost everywhere.' Today, Milk Thistle is a fairly rare sight in Britain – but this is not the case in other parts of Europe.
Where to find Milk Thistle
On sunny slopes in Mediterranean countries, particularly Spain and Greece, Milk Thistle grows so vigorously that it often forms beautiful but impenetrable wastelands. The plant is more sparsely distributed in Britain, Australia, New Zealand, southern regions of the US, Africa, India, Asia and South America.
If left to grow and propagate without interference, Milk Thistle will soon establish itself, by way of its 'parachute' system of seed distribution.
The plant prefers a sunny location and, like all thistles, it is hardy and adaptable even in cold damp conditions.
Milk Thistle is grown commercially on plantations throughout the world (mainly Argentina, Australia, Texas, Russia, China, Germany, Romania and Hungary). It grows most successfully in hot regions with low to moderate rainfall and it is usually grown organically. I have known of organic commercial crop failures in the UK, when a colder wetter summer failed to produce the harvestable brown seeds.
The plant is cultivated as an annual. The seeds are sown directly into the ground and the plant grows quickly to a height of 2 m (6 ft). It requires relatively little attention – weeding is unnecessary – and it is fairly pest-resistant.
Milk Thistle prefers light, well-drained soil. Commercial growers also favour a light, friable soil, because it makes the removal of the old plant following harvesting a swifter process. It is also easier to plant the seeds for the following year’s crop in this type of soil.
Milk Thistle is a great coloniser of cultivated ground, which is why steps were taken to stop it spreading across farmland. However, soil rich in artificial fertilisers (nitrogen in particular) may have an adverse effect on the plant.
A History of Healing
Milk Thistle was once called the Venus Thistle and was dedicated to Freya, the Norse goddess of love and beauty. In the first century AD Pliny described it as excellent for removing bile, while Dioscorides recommended it for melancholy and snakebite. When the Roman armies travelled across Europe, they took Milk Thistle seeds, leaves, stalks and roots with them to provide food and medicine.
It is probable that Milk Thistle found its way to Britain through the Romans, where it gained a reputation as a gentle healing plant.
In medieval times it was believed that the plant's markings and milky sap were created by milk falling from the Virgin Mary's breast as she suckled the infant Jesus, giving rise to the folk names of Holy Thistle, Our Lady's Thistle and St. Mary's Thistle.
Herbalists described the plant as 'a great breeder of milk and a proper diet for wet nurses'. This has been disputed, but modern herbalists find that Milk Thistle does actually improve lactation.
The herbalist Gerard stated, 'My opinion is that this is the best remedy that grows against all melancholy diseases'.
In the 17th century, the famous British herbalist Nicholas Culpeper recommended Milk Thistle for curing agues and the plague. He claimed that 'it provoketh urine and breaketh and expelleth the stone and is good for the dropsy'. He also considered it helpful for relieving 'a pain in the side' – possibly a 'stitch' or discomfort in the region of the liver. He gave instructions for its use in removing obstructions of the liver and spleen and curing jaundice. A decoction of the seed was to be taken internally or applied to the affected area as a compress.
Collective research from a number of countries worldwide has now shown that silymarin, a chemical constituent of Milk Thistle seeds, has a protective and regenerative effect upon the liver. This also positively affects the memory and disposition. Culpeper also suggested eating the young plant in spring to cleanse the blood and improve circulation. Similarly, recent research suggests that the powdered seed may eventually be of use in the treatment of some cardiovascular disorders.
Later herbals recorded that all parts of Milk Thistle could be eaten to stimulate the appetite and assist digestion by relieving dyspepsia. Powdered seed was used to treat menstrual problems, difficulty and pain in passing water, leg ulcers, and varicose veins. The sap from the plant was considered to be an aid to achieving a fair, white skin.
Native Americans used Milk Thistle as a remedy for boils, skin diseases, and some forms of poisoning. During the late 1800s, when the Eclectic Medical College of Pennsylvania was founded, it became an important herb in the practice of naturopathic medicine.
Milk Thistle’s healing properties were first discovered through practical experience rather than through pharmacological research carried out by scientists. The historical reputation of Milk Thistle as a healer of liver disorders then encouraged scientists to research this aspect more thoroughly.
In 1848, a German scientist, Johannes Gottfried Rademacher, showed that the herb was of great value in treating liver conditions such as viral hepatitis and jaundice.
Over the last fifty years, scientists have succeeded in identifying the active ingredients in Milk Thistle, most notably a group of three related flavonoid compounds, which are collectively named silymarin. Experiments have proved conclusively that silymarin protects the liver from damage from a variety of toxins. (However, its mechanisms of action are still not fully understood.)
The most amazing of these experiments revealed that silymarin could reverse the deadly effects of eating the death cap mushroom (Amanita phalloides), which contains some of the most potent liver toxins known to humankind. They can cause permanent liver damage or death, within a few hours of ingestion.
Research in Germany and the United States suggests that Milk Thistle is invaluable in the treatment of liver damage caused by alcoholic cirrhosis, fatty degeneration, and the effects of pharmaceutical drugs, anaesthetics, and poisoning. It has also been found useful in the treatment of psoriasis.
Anatomy of Milk Thistle
The whole of the Milk Thistle plant, including the root, was used for therapeutic purposes in the past. Modern research has shown that the plant’s most valuable constituent, silymarin, although found in all parts of the plant, is at its most potent and accessible in the seeds.
Stems and leaves
The stem of the Milk Thistle contains a milky-white sap. Tender young stems may be eaten as a nutritious vegetable.
The large scalloped leaves have prickly edges and streaky white markings along the veins (these also contain a milky sap). Young leaves can be eaten as a vegetable, and can aid digestion and improve appetite. Leaves may also be dried and made into a tea. Both stem and leaves were, at one time, recommended as a diuretic.
The stems and leaves contain many of the same constituents as the seeds, but at a lesser strength, and are therefore less effective for therapeutic purposes. They are, however, ideal as a food and the flavour of the leaves will promote appetite, encourage bile flow, and enliven liver function.
SHELF LIFE OF LEAVES
Fresh leaves will keep for 3 days in the refrigerator; dried leaves last for 1–2 years if stored in dark, airtight containers.
Flowers and seeds
The violet-purple flower heads of Milk Thistle are solitary, spiny, and thistle-like. After the flower dies, thick white thistledown appears with green immature seeds which slowly ripen to become brown. Once truly ripe, they loosen and the white thistledown becomes their flying 'parachute' to allow the seeds, which contain the most valuable healing constituents, to disperse themselves.
The flower buds can be eaten as a vegetable; the dried flowers can be made into teas and taken for their tonic effect. Besides the seeds’ main use as a liver healer, they may also be used to treat fungal infection, food allergies, and high blood pressure.
Shelf life of flowers and seeds
Fresh flowers in water last 4 days; dried flowers last 6–12 months. Fresh seeds last 3 days; dried seeds last 1–2 years in dry conditions – after that their fatty stores deplete and they become more wizened and lose their pleasant taste and nutritional value.
The seeds contain essential oils, unsaturated fatty acids, bitter compounds, polyacetylenes and a group of flavonoids collectively known as 'silymarin'.
Silymarin is virtually insoluble in water, making aqueous preparations less effective. The component of silymarin that yields the greatest degree of biological activity is called silybin.
Although there is a white variety of the plant, it is the seeds of the purple variety that are richest in beneficial substances. Also, analysis of wild Milk Thistle seeds gathered from more southerly countries revealed that they had markedly higher silymarin content than those from northern regions. Rainfall, average temperature and genetic heritage also affect the production of silymarin by the plant.
The seeds also contain starch, protein and oil. The fatty acid content is 20–25 per cent, of which the principal constituents are the omega 6 essential fatty acid linoleic acid (50–60 per cent), and the omega 9 oleic acid (25–30 per cent).
The flavonoid content is 2–5 per cent. Milk Thistle flavonoids are important anti-inflammatory and antioxidant components. They function as 'biological response modifiers' in the body, not acting against but modifying the body's responses to, allergy, viruses, carcinogens and inflammation. Flavonoids can also help to strengthen capillaries, so can be useful when there is evidence of increased capillary fragility, with symptoms as varied as easy bruising, vascular disease, some allergic states, haemorrhoids, diabetes mellitus and oedema.
Milk Thistle in Action
For centuries, Milk Thistle has been used to treat a variety of ailments. Modern medical research has proved that the plant is useful for treating liver problems: the seeds contain silymarin, which protects and regenerates the liver. Milk Thistle has no known adverse effects on the body.
How Milk Thistle can help
Milk Thistle has a major effect on a number of vital body functions:
- Stimulates and improves the function of the liver and gallbladder and aids bile flow.
- Encourages bowel movement and removes toxicity that may have built up in the bowel.
- Clears the kidneys, promoting better urination.
- Through its effects on the liver and other channels of elimination, it can help to clear the skin and relieve skin ailments.
- Helps soften kidney stones and gallstones.
- Helps to remove excesses of oestrogen in the body, which can provoke conditions such as fibroids.
- Alleviates painful menstruation and is an invaluable all-round pre-menstrual herb.
- Helps lower 'bad' LDL cholesterol levels.
- Reduces cancer cells in breast, cervix, prostate and bladder cancer and very likely other cancers.
- Aids type II diabetes as it can have a beneficial effect on blood glucose regulation.
Many conditions that benefit from Milk Thistle are 'diseases of civilisation' – those provoked by environmental toxins, prescription drugs or high-sugar / high-fat foods which all put pressure upon the liver by loading it up with extra work.
Eliminating as many causative factors as possible whilst using Milk Thistle as a back-up treatment for the liver will help restore health and protect against future damage.
The French traditionally considered the liver to be more important for general well-being than any other organ and Milk Thistle was relied on to protect against consuming too much alcohol.
Silymarin – how it works
- Milk Thistle's most active components are a complex of flavonoids known collectively as silymarin, which contain silibinin, silidianin and silcristin. Silymarin works very simply: by altering the structure of the outer membrane of the liver cells, it prevents poisons from entering those cells and stimulates the regeneration of damaged cells by increasing cell division.
- Silymarin acts as a scavenger of free radicals, neutralising toxic invaders. It also promotes the release of superoxide dismutase – a powerful antioxidant produced in the body that appears to be specifically effective in scavenging the free radicals produced as the liver processes alcohol.
- Silymarin's powerful effect on the liver is due to the way it is absorbed through the intestines (with bile), processed by the liver, then removed from the liver again in the bile, to be reabsorbed again from the intestines. This continual cycle ensures that silymarin is concentrated in the liver.
- Beyond this there are still many mechanisms within Milk Thistle that are still not fully understood. It is possible that it concentrates in the hepatocytes (liver cells) and competes with toxins for hepatocyte binding and penetration.
How Milk Thistle affects the liver
- Strengthens and stabilises liver cells and cell walls, preventing many toxins from breaking through fatty cell membranes and entering the cells.
- Neutralises toxic substances that do break through.
- Induces the formation of liver cell proteins, which strengthen the liver and make it more resistant to toxins.
- Stimulates protein synthesis in liver cells by increasing DNA and RNA activity, enhancing the rejuvenation of liver cells.
- Boosts the activity of antioxidants. In particular, it prevents the depletion of glutathione in liver cells. Glutathione is one of the most powerful antioxidants and detoxifies many hormones, drugs and chemicals. Raising the level of glutathione increases the capacity for detoxification.
- Helps reverse alcohol damage by normalising the ability of the liver to make phospholipids, including 'good' HDL cholesterol, which insulate the brain. Without cholesterol, the brain shrinks in the face of sustained alcohol consumption.
- Stimulates production of new liver cells and inhibits formation of damaging leukotrienes.
Summary of liver, gallbladder and bile support
Milk Thistle is most specifically of value in treating liver and gallbladder problems, jaundice and conditions that may be the result of a 'sluggish' liver and lack of bile function.
Liver disease has many diverse causes, some of which are self-inflicted. Although Milk Thistle can be very effective, it cannot heal if the body is continually abused. It should not be considered an easy alternative to making improvements to diet and lifestyle.
In the 1970s, two German research groups led by E. Kaisewetter and R. D. Schopen proved through clinical studies that 70 per cent of patients suffering from chronic liver disorders had a vastly improved chance of recovery when given between 210 and 420 mg of silymarin daily over periods ranging from six weeks to two years. The silymarin reversed liver damage and decreased levels of the liver enzyme transaminase in the blood (raised levels are evident in hepatitis).
Silymarin has also been shown to reverse the effects of highly toxic alkaloids such as phalloidin and alpha-amanitin, found in the death cap mushroom. In 1981, Dr Vogel of the University of Munich treated patients who had been poisoned by this mushroom. Daily injections of silymarin reduced the death rate to zero, whereas the expected death rate would have been 30–40 per cent. He concluded from this that Milk Thistle interfered with the circulation of poison in the liver cells, protecting them from further damage and healing and regenerating those already damaged.
Clinical studies have shown that in cases of acute hepatitis, recovery time is halved when patients are treated with silymarin. In cases of alcoholic hepatic cirrhosis, the survival rate of patients treated with silymarin over a five-year period increased nearly threefold.
Where alcohol causes fatty degeneration of the liver, tests have shown that treatment with silymarin can result in an 80 per cent improvement in the regeneration of the liver.
Heavy metals, pesticides, organophosphates and other pollutants may be inhaled or absorbed through the skin and their effects not felt for some years, by which time the toxins have lodged in the liver and caused serious damage. The resulting symptoms vary from nausea, tiredness, memory loss and skin disease, to severe hepatic disorders. Since 1969, extensive ongoing clinical trials have proved conclusively that silymarin is a potent liver-protecting substance, which both reverses the effects of these toxins and heals damaged liver cells.
During the early 1990s, Italian scientists started research into making a new Milk Thistle product, which is said to be more easily absorbed. Silybin, the most highly active component of silymarin, was combined with phosphatidylcholine to produce a product called silipide. When S. Mascarella at the Institute of Clinical Medicine in Florence tested it on patients with either viral or chronic alcohol-induced hepatitis, it produced very positive results with remarkable decreases in enzyme levels. Further tests showed that patients with long-term chronic hepatitis B and hepatitis C had a vastly improved liver function. Other trials did not show these improvements, however.
Other support offered by Milk Thistle
Trials show that Milk Thistle can help various cancers (breast, kidney, prostate, and bladder), by various means. These include decreasing blood supply to tumours, helping stop cancer cells from dividing and shortening their life span.
In 2006, clinical trials on Milk Thistle and diabetes showed that in type II diabetes a beneficial effect on glycaemic profile was clearly visible after four months.
Chemotherapy and Milk Thistle: as a profound anti-inflammatory, Milk Thistle was given to 50 children on chemotherapy in a study at Columbia University Medical Centre in New York. After one month, researchers found lower levels of two liver enzymes and less inflammation. Additionally these children did not need their chemical levels lowered to accommodate the high inflammation levels.
When to avoid Milk Thistle
Milk Thistle has been widely used as a medicinal herb over a long period of time and its very low toxicity makes it invaluable for long-term use.
Use alongside drugs
For some time it was postulated that Milk Thistle may affect the uptake and efficacy of drugs, either by unduly speeding up or slowing down their action. Many drugs are metabolised via the cytochrome P450 system in the liver, so anything that interferes with this pathway (speeding it up or slowing it down) is potentially dangerous or disadvantageous. Milk Thistle is thought to affect this detoxification pathway and is so extremely quick at removing toxins that it was thought it would clash with these drugs. Certain drug-on-drug interactions which both use this P450 system, e.g. acetaminophen (paracetamol) have caused extreme liver damage. However, according to a 2005 assessment at the University of Arkansas for Medical Sciences, Milk Thistle is of minimal risk and showed little effect on CYP450-metabolised drugs. For more information, go to http://www.ncbi.nlm.nih.gov/pubmed/15536458. So to conclude, Milk Thistle's use and effect on human cytochrome P450 phenotypes has proved largely safe and it is not thought to be of undue concern for interfering with drug uptake or efficacy.
However, there is still a blanket warning not to use Milk Thistle for those on the birth control pill, on anti-psychotics, seizure medication and anaesthesia drugs. Please refer to your doctor if you are taking this type of medication or if you have any other concerns regarding interactions.
Pregnancy and breastfeeding
All 'over-the-counter' remedies of Milk Thistle carry a blanket warning not to use during pregnancy and breastfeeding. A qualified herbalist in a clinic setting would be able to discuss this with you.
Allergies to Compositae or Asteraceae family
The above botanical family (the daisy family), of which Milk Thistle is a member, create allergies for some. Please avoid Milk Thistle if you know you have an allergy to this botanical family.
As Milk Thistle is a detoxifying herb, initial side effects such as slight nausea, headache, skin rashes or mild diarrhoea may occur. These effects will soon pass.
Energy and Emotion
Milk Thistle is a tonic herb with a dual action. It is warming and drying, as well as gentle, cooling, and protective. It stimulates the circulation, banishes sluggishness, and promotes a sense of good health and general well-being.
Milk Thistle positively affects not only the liver but also the kidneys, heart, lungs, bladder, and uterus. The tonic, pleasantly bitter taste of the fresh herb, tincture, or tablets gives some indication of the plant’s cleansing effects. A ‘stagnant’ liver can create emotional as well as physical problems such as depression, irritability, and melancholy. Milk Thistle is invaluable here, because it detoxifies the body, bringing about a more positive frame of mind, together with a greater zest for life.
Other physical effects will become apparent: the lungs will relax and function better; the adrenal and endocrine glands will be stimulated (resulting in enhanced kidney and hormonal function); the circulation will improve and the mind will become clearer.
Energy and the mind
In the 1st century AD, the Greek healer and philosopher Dioscorides put forward the idea in the Doctrine of Signatures that a plant’s appearance indicated its potential effects on the body. It would therefore follow that the almost glacial appearance of Milk Thistle, with its erect and perfectly balanced formation, would have a cooling and balancing effect on the mind, dispelling feverish and introspective thoughts, and encouraging clarity and contentment. The fact that it was at one time eagerly sought after as a tonic plant shows that it was valued for bringing people out of the doldrums, restoring not only health but mental energy as well. The marbled, milky look of the leaves lent credence to its use as a ‘galactagogue’, a herb that encourages breast milk production. Milk Thistle is able to encourage milk production, mostly because it balances almost every system in the body, bringing a sense of well-being and calm.
Milk Thistle is an elegant plant that stretches up from its wide, leafy base to large, violet-purple, thistle-shaped flowers. The plant resembles a magnificent crowned deity. The flowers reflect abundance and a generous spirit, helping anyone who needs a lift out of the doldrums – physically, mentally, or spiritually. You can make a flower essence from Milk Thistle to capitalise on these qualities. Flower essences are said to contain the life force of the flower itself, and to balance the energies of mind and body.
To make a flower essence – standard quantity
- Use approx.. 350 ml (1½ cups) each of spring water and brandy, and 3–4 carefully selected Milk Thistle flowers (use buds and flower heads) that should be picked in the early morning.
- Choose a very quiet spot indoors – or in a secluded area of the yard or sunny woodland if the weather allows. Place the flowers, while still fresh, in a glass bowl with the spring water, ensuring there is enough water to cover them and that they are fully submerged.
- Cover the bowl with clean white cheesecloth or muslin; put in a sunny position.
- Leave the bowl in the sunshine for several hours – perhaps next to a window if you are indoors. Try to ensure that the flowers have at least three hours of continuous sunshine. If they wilt sooner than this – which they may do in fierce sun – then they can be removed earlier.
- After the three hours or so remove the flowers and discard them, using a twig to lift them out of the bowl.
- Add an amount of brandy equal to the remaining amount of water and flower mixture, to preserve the liquid. Pour the liquid into dark glass bottles and label carefully.
Adults: 4 drops under the tongue four times daily, or every half-hour in times of crisis.
Children: Over 12 years, adult dose. 7–12 years, half adult dose. 1–7 years, quarter adult dose.
Plant spirit energies
The spirit energy of Milk Thistle is one of optimism, recovery, and life. The liver was once thought to be the seat of love and violent passion, and the source of life. The recovery of the liver was therefore seen as a renewal of life.
This hardy plant puts all its energy into the brilliant flower-head, which in turn produces seeds that scatter far and wide to colonise and thrive in the most adverse conditions. It is this ability to regenerate itself that is the spirit energy of Milk Thistle. Strong, generous, and adaptive, it is a plant that is extraordinarily well suited to dealing with the wide range of illnesses, imagined or otherwise, that confront people in a modern world beset with environmental and social problems.
Growing, Harvesting and Processing
Milk Thistle grows well on light, friable soil with good drainage. Dry, constant heat suits it best and gives the highest silymarin yield in the seeds. However, it will flourish in any sunny position. It prefers light watering.
Growing Milk Thistle
In the damp climate of Britain, the plant will produce a lot of foliage growth, whereas in the Mediterranean and other hot regions a more upright, spindly plant with smaller leaves and more flowers and seeds results. Ideally, in cooler climates seeds should be sown as early as possible in the spring; in hotter countries a sowing in the autumn is preferred because otherwise the season is too short and the yield smaller.
Commercial growers protect the seed heads from heavy rain, wind dispersal, and birds by loosely covering them with waxed paper or muslin bags.
Milk Thistle can be grown without difficulty in most gardens, but remember that the seed heads should be protected from wind – the parachute top makes it a very adept flyer, and you may lose your crop. It is a statuesque plant and will grace any garden.
You do not need to prepare the ground or add any nutrients.
Sow the seeds to a depth of 2.5–5 cm (1–1½ in) in rows roughly 60 cm (2 ft) apart. Alternatively, leave some seed heads to reseed and establish a random planting. After sowing, water lightly. The seeds take 8–10 days to germinate, and the first flowers unfurl 80–90 days after sprouting. The whole process, from the seedlings’ first appearance to seed gathering, takes 110–140 days. If you wish to collect the seed, protect it from wind and birds with muslin bags.
Milk Thistle grows quickly and requires minimum attention. When the plants are developing they will need minimal watering. A little light weeding may be needed to keep them free from invaders, but the plants will soon cover the ground and stop other weeds taking hold. Do not use weedkillers – Milk Thistle is categorised as a weed, and you will kill off your crop.
After harvesting, pull up the old plants immediately. Remember to save some seeds to sow the next year. Remember, you can eat the roots.
Methods of harvesting vary considerably. In some countries it is carried out manually, but on commercial plantations, particularly in Europe, the process is usually mechanised. The crop is harvested by combine. The dried, cleaned seeds are stored in sacks in a ventilated warehouse, to be distributed all over the world.
Thick gloves, protective clothing, and a pair of clippers are essential items of equipment for collecting Milk Thistle seed heads. The plant flowers in early summer and the seeds are harvested in late summer. Timing is very important: seed heads are ready for collecting when they reveal a profusion of white parachutes – these contain the ripest seeds. However, if you leave the harvesting too late, the wind will take much of the crop, unless you have been able to cover the seed heads.
Cut the seed heads at about 2.5 cm (1 in) down the stem, and place them head down in a large plastic bucket. If the seeds are ripe, shaking the seed heads should be enough to release them from their anchorage. Place the seeds or seed heads in a clean, dry, ventilated container ready for processing.
Very little processing is required apart from extracting the small, hard seeds from the fluffy down, bracts, pieces of stem, and leaves. It is usually only necessary to dry out the seeds in damp climates, because the seeds have minimal water content and tend to be very dry on the plant – especially as harvesting will have been timed to coincide with optimal weather conditions. However, the seeds may be vacuum-dried to prevent the growth of mould or bacteria, which can cause the seeds to rot.
Ensure that the seeds are totally separated from any down, bracts, or leaves, and are dry. This is best achieved by placing the seeds on absorbent paper on a wire rack. If you harvest in dry weather no further drying is needed but if you are forced to harvest in wet weather, then place the seeds on a rack in an oven preheated to 100°C (212°F) with the heat turned off and the door left open for between 30 minutes and 1 hour. When you feel the seeds are dry enough, put a handful in a glass jar, cover with an airtight lid, and then let it stand in the sunshine for at least two hours. If water droplets appear on the inside of the jar, there is still some moisture in the seeds and therefore a risk of spoilage, so you should remove the contents from the jar and dry them for a while longer. When the seeds are completely dry, store them in an airtight jar in a cool, dark place.
Preparations for Internal Use
One of the least complicated ways of enjoying Milk Thistle seeds is to chew them just as they are: they have a great taste and are a good source of instant energy. Toasted and ground, they take on a delicious new dimension – sprinkle a teaspoon on food.
Milk Thistle tincture
Silymarin is virtually insoluble in water, so extracts need to be made with alcohol, glycerine, or olive oil. Tinctures are made with alcohol. But alcohol is, in itself, a liver toxin, and to be avoided by those with liver complications. An alternative is to take tablets, capsules, or a cold-pressed maceration in glycerine or olive oil. However, silymarin is less easily absorbed in these forms, so it is necessary to ensure that you are using a concentrated and standardised product. Tinctures are very readily absorbed into the body and are, for this reason, preferred by herbalists.
Note: Always use utensils that have been cleaned in boiling water – and for good results add one or two drops of lavender, thyme, or tea tree essential oil to the cleaning water.
To make a tincture – standard quantity
- As a rough guide, use 220–310 g (1–1½ cups) of Milk Thistle seeds to 250 ml (1 cup) 80 per cent proof vodka, and 750 ml (3 cups) water.
- Put the seeds into a blender or food processor and pour on the alcohol. When blended, pour into a dark glass jar or kilner jar, cover with an airtight lid, shake well, and label carefully. Store in a cool, dark place for 2 days, shaking the jar each day to help the extraction process.
- After two days, add the water to the mixture. If you have only used 37–45 per cent proof vodka, use only 20 per cent water relative to the volume of the mixture. Leave the jar for 2-4 weeks, and shake it daily.
- Strain the tincture though a jelly bag, preferably overnight, until you have the last drop of liquid. For best results use a wine press.
- Pour the tincture into sterilised dark jars or bottles, label clearly, and store in a dark place. For personal use, decant into 50 ml (2 fl oz) tincture bottles.
Adults: 5ml (1 tsp) 1–2 times daily.
Children: over 16 years, adult dose. For children under 16, consult a qualified herbalist.
Milk Thistle decoction
A decoction is not the best way of benefiting from Milk Thistle’s powers, because water alone fails to release silymarin satisfactorily. However, the amount of silymarin and other chemical components that do succeed in percolating into water can help to make a decoction moderately effective against indigestion, depression, and headaches. For the unpleasant, bloated biliousness symptomatic of liver disorders, a strong decoction is a good way of harnessing the plant’s chemical constituents.
To make a decoction – standard quantity
- Use 7 g (¼ oz) of dried or 40g (1 ½ oz) fresh Milk Thistle seeds to 750 ml (3 cups) cold water, which should reduce to about 500 ml (2 cups) after simmering.
- Put the seeds and water in a large pan or double boiler. Boil for 1 minute, and then simmer on a very low heat for 20–30 minutes. The liquid should reduce by a third.
- Let cool, then strain through a sieve into a pitcher. Drink while warm, or refrigerate for up to 3 days.
Adults: 3–4 cups daily.
Children: over 16 years, adult dose. For children under 16, consult a herbal practitioner.
Case study – alcoholism
Ewan had been told that if he did not stop drinking, the damage to his liver would be irreversible. He enrolled on a private treatment course in which Milk Thistle played a major part. Within a week he no longer felt nauseous and his appetite returned. After a month, his skin improved and he felt physically stronger. The Milk Thistle also reduced the craving for alcohol by eliminating toxins from the liver.
As part of his treatment over the next year he took 2 capsules of a 70 per cent silymarin standardised extract every day, and now continues with a maintenance dose of 1 capsule a day. He now enjoys a vastly improved state of health and a normal lifestyle.
Liver maintenance drink
One of the best ways of maintaining good health is to keep the liver functioning well. A liver-cleansing programme which includes regular ‘liver drinks’ is an excellent way of achieving this. Make up the recipe below.
To make the liver drink
- Juice of 1 freshly squeezed lemon (add a little peel zest if organic)
- 250 ml (1 cup) apple juice, preferably freshly made
- 250 ml (1 cup) spring water or more
- 1 garlic clove (peel and crush before putting into the blender)
- 15 ml (1 tbsp) extra virgin olive oil
- 0.5 cm (¼ in) piece of ginger root, peeled and chopped (not to be included if your liver feels hot or inflamed).
Liquidise the ingredients until well blended. Drink slowly. After 15 minutes, drink a cup of hot peppermint tea, followed by some organic apple juice.
Try this once, and then repeat after a few days depending on how you feel. Keep going for 3–5 days if you feel good, or give yourself a break of a few weeks if you feel tired and low and then resume, one day at a time. During this time eat sensibly, using wholefoods and avoiding tea, coffee, alcohol, and all junk food. You may experience headaches and feelings of sadness or anger at first, but these will soon be replaced by joy and enthusiasm once the cleansing has had time to work.
Milk Thistle tablets and capsules
Powdered Milk Thistle seed is used to make commercial brands of tablets and capsules. The tablets or capsules usually contain 70–80 per cent standardised extract of silymarin in an 80–200mg dose; 1 to 2 tablets or capsules a day is usually suggested. Milk Thistle is sometimes put with other protective and healing 'liver cleansing’ herbs such as Dandelion, Barberry, Turmeric, Artichoke, Gentian or Ginger.
How are the tablets and capsules made?
One of the commercial processes for making Milk Thistle capsules starts off in a similar way to the production of a tincture. Alcohol is used to dissolve the active chemicals in the seeds, and is then evaporated off so that there is none in the finished product. As a result, this is a good way for recovering alcoholics (or others who prefer to avoid any alcohol) to take Milk Thistle. Each extract is then tested and adjusted so that the strength of the silymarin content is uniform.
Non-standardised Milk Thistle capsules can also be made quite simply at home by using powdered seeds in vegetable cellulose capsules.
To make capsules – standard quantity
- Approx. 250–300 mg of powdered seeds fits into a size 00 capsule.
- Put the finely powdered Milk Thistle seeds in a saucer. The easiest way to grind the seeds to a fine powder is to use a pestle and mortar, or to process them in a small coffee grinder. Freshly powdered seed is the best quality.
- Open up the capsule. Using the ends as shovels, scoop up the powder, pushing the two halves of the capsule together until they are full of powder (one end will contain slightly more than the other).
- Join the two ends together carefully, so that you do not lose any of the powder.
Adults: 1 capsule 2–3 times daily.
Preparations for External Use
Milk Thistle can be used effectively as an external compress. A castor oil pack, although it does not use Milk Thistle, is a useful back-up to treatment programmes for liver problems.
A Milk Thistle compress can be very soothing, especially for the pain and stiffness caused by arthritis. The addition of castor oil will increase the overall benefit.
To make a compress – standard quantity
- Use 20 g (¾ oz) Milk Thistle seeds and approx. 30 ml (1 fl oz) castor oil.
- Put the Milk Thistle seeds into a mortar with enough castor oil to make a thick paste, and pound them. Alternatively, grind the seeds in a blender, adding just enough castor oil to allow the blades to turn easily. It will make the process easier if the oil is warmed first. This also makes the compress pleasantly warm. In some circumstances, however, a cold compress is called for – in which case let cool before using.
- Apply the sticky seed compress directly to the area to a thickness of approximately 0.5 cm (¼ in) and cover it immediately and firmly with plastic wrap. This keeps everything sterile and removes the necessity for using bandages. Leave on for 20 minutes to 1 hour. Repeat 24 hours later if necessary.
Castor oil pack
A castor oil poultice or ‘pack’ alleviates pain and inflammation resulting from liver problems. It draws out toxins and disperses congestion.
To make a castor oil pack – standard quantity
- Use 225 ml (8 fl oz) castor oil.
- Place the castor oil in a pan (a double boiler is ideal). Warm the oil gently to a temperature suitable for placing on the skin.
- Cut a double thickness piece of cheesecloth to the size of the liver (about 20 cm/8 in square). Dip it into the warm castor oil and place directly over the liver.
- Cover the castor oil pack with plastic wrap, wrapping it right around the torso to secure it. Place a hot water bottle over the area and leave for between 20 minutes and 1 hour.
- The procedure can be repeated every four hours over a day. When removing the pack simply cut through the plastic wrap. The cheesecloth and oil can reused once or twice. However, if the pack is stained, discard it, because this indicates that toxins have been drawn out.
Natural Medicine for Everyone
Milk Thistle is believed to be safe for everyone, even those most vulnerable members of society. However, see below for suitability and cautions for different population groups. See the page above 'When to avoid Milk Thistle' for information on its use alongside medication.
Pregnancy and breastfeeding
Milk Thistle is considered by most herbalists to be gentle enough to ensure that there are no adverse effects when taken during pregnancy. It can assist the balanced working of all organs and reduce the side effects of any drugs. It helps banish morning sickness as well as motion sickness. It also lessons the likelihood of both varicose veins and haemorrhoids, which are often caused by poor circulation during pregnancy. Historically, Milk Thistle was thought to encourage good milk production in nursing mothers because it brought about a sense of well-being and calm. The latest research seems to support this.
However, the Medicines and Healthcare products Regulatory Agency (MHRA) in the UK advises on their product information sheets for licensed over-the-counter Milk Thistle supplements (those registered as a Traditional Herbal Remedy) that the product should not be used while pregnant or breastfeeding. For this reason, it is advised that you consult a qualified herbalist if you wish to take Milk Thistle when pregnant or breastfeeding.
Children and teenagers
If you wish to use Milk Thistle for children under 16, seek advice from a qualified herbalist beforehand, or confine the use to a few seeds in food.
Children are less likely to suffer damage from toxins such as alcohol, so do not need to take Milk Thistle on a regular basis. However, when taken as a preventative or as a support to other treatment, Milk Thistle can have many beneficial effects. When taken alongside medication prescribed for allergy, infection or chronic illness, it will ensure there is no toxic build-up in the liver. It will regulate the working of the liver, kidneys and bowels and help boost the immune system.
Milk Thistle is also effective in helping to clear skin conditions that break out in puberty and develop into acne during the teenage years.
Milk Thistle can help to relieve many health problems associated with old age, because it helps to promote the smooth function of all the internal organs. As a liver cleanser, it reduces the risk of liver malfunction and the painful, debilitating conditions that may arise from this. Milk Thistle also stimulates the kidneys, bowels and gallbladder into functioning better and improves circulation which, in turn, leads to improved mobility and sharper memory. These factors help to enhance quality of life during old age.
As a support herb for the long-term treatment of serious illness, Milk Thistle can prevent some of the side effects of pharmaceutical drugs that many older people may be routinely taking. It helps the organs and the circulation regain a natural, balanced routine, which may have been inhibited by surgery, convalescence or immobility. Do be aware however of the numerous medications alongside which Milk Thistle should not be used. See ‘When to avoid Milk Thistle’.
Herbal combinations are used when the effects of a single herb need complementing in a particular way. If you are pregnant or breastfeeding, have a serious medical condition or are on prescribed medication, you should consult your doctor or a qualified herbalist before trying these combinations.
This formula can be used for poor digestion, biliousness, and feeling of being generally ‘out of sorts’. It is a balanced, powerful combination, with a strong flavour.
Formula: 2 parts Milk Thistle seeds, 1 part Dandelion root, 1 part Fennel seeds, 1 part Ginger root. Make up as a tincture.
Adults: 5 ml (1 tsp) taken 3–5 times a day in 50 ml (10 tsp) of water or fruit juice.
Dandelion removes excess water from the body and through supporting the kidneys, ensures removal of the toxins that have been pulled out of the liver; it also acts as a tonic and stimulant. Fennel arouses appetite and relieves flatulence. Ginger is warming, cleansing, calming, and stimulates the appetite. Together with Milk Thistle, these herbs cleanse and regenerate, giving an improved sense of well-being.
This formula improves the elimination of addictive substances from the liver, such as caffeine, nicotine, alcohol, and the chemical compounds of non-prescription drugs and prescription drugs that are no longer being used. Eliminating all traces of such toxic substances improves the chances of kicking the habit. This process can take between a few weeks and several months.
Formula: 2 parts Milk Thistle seeds, 1 part Dandelion root, 1 part Passion Flower, 1 part Lavender flowers. Make up as a tincture.
Adults: 5 ml (1 tsp) 4–6 times daily in 50 ml (10 tsp) water or fruit juice.
Milk Thistle will activate liver and bile function whilst repairing and renewing damaged cells. Dandelion promotes bile flow and kidney balance, encouraging toxins to be cleared quickly and efficiently. Passion Flower and Lavender calm the nervous system and help to relieve anxiety, making the process of detoxification easier and less stressful.
(Add Ginger if there is nausea.)
Pre-menstrual syndrome (PMS)
This formula can help during the ten days before menstruation, when a variety of symptoms can occur, including fatigue, emotional disturbance, water retention, painful breasts, and cramps.
Formula: 3 parts Agnus Castus berries, 2 parts Milk Thistle seeds. Make up as a tincture.
Adults: 7–8 ml daily, taken in the morning as a single dose.
Agnus Castus is a hormone regulator that increases the activity of progesterone and thereby balances excessive oestrogen production. This is very helpful during the premenstrual phase when there is often a shortage of progesterone and a dominance of oestrogen, causing pain, water retention, and other unpleasant symptoms.
Milk Thistle assists in clearing the liver to remove excess hormones. This is helpful pre-menstrually because if hormones build up and are unprocessed by the liver, unpleasant symptoms such as feelings of depression and anger may arise.
Gastroenteritis is characterised by inflammation of stomach and intestines. Its causes include bacterial food poisoning, infection, and stress. During an attack of gastroenteritis, the work of the liver, spleen, and stomach is impaired and needs support. These organs will also need stimulating and balancing, for which the bitter, pungent tastes of this formula are vital.
Formula: 2 parts Turmeric rhizome, 2 parts Milk Thistle seeds, 1 part Clove buds, 1½ parts Cinnamon bark. Make up the formula as a tincture.
Adults: 5 ml (1 tsp) hourly until acute phase subsides, then 5 ml (1 tsp) 3–4 times daily.
Turmeric is a liver cleanser with antiviral capabilities. Milk Thistle calms the stomach, easing nausea, and establishing correct liver function and normal production of bile. Cloves tackle any bacterial or other microbial infection. Cinnamon is soothing and its flavour will further ease the condition by balancing the bitter-tasting herbs in the formula.
This skin disorder is a common problem and affects the outer layers of the skin. Liver clearance is vital.
Formula: Equal parts of Barberry root bark, Cleavers herb, Milk Thistle seeds, and Echinacea root. Make up as a tincture.
Adults: 5 ml (1 tsp) 3 times daily.
Barberry improves bile flow and is a recognised plant for alleviating psoriasis, mainly due to its high alkaloid content. Cleavers herb is a valuable diuretic and is renowned for its efficiency in healing a variety of skin disorders. It is a general detoxifier and helps to reduce swollen lymph glands. Milk Thistle clears and cools the liver, thereby helping the whole body to function much more effectively. Echinacea will provide much-needed immune modulation. If stress is a causative factor, herbs to support the nervous system may also be included. For information on these, consult a qualified herbalist.
Shingles is a viral infection that causes very irritating rashes. To alleviate the symptoms, it helps to support the nervous system and cleanse the liver.
Formula: 2 parts Echinacea root, 2 parts Gotu Kola leaves, 2 parts Milk Thistle seeds, 2 parts Siberian Ginseng root, 1 part Oat straw. Make up as a tincture.
Adults: 5 ml (1 tsp) 3 times daily.
Echinacea helps to fight the virus that causes shingles by stimulating a strong immune system response. It also supports the beneficial action of the other herbs.
Gotu Kola is an all-round tonic herb renowned for clearing skin problems and helping to strengthen the nervous system. Milk Thistle takes the ‘heat’ out of the rash and decongests the liver while cooling the body. Both Siberian Ginseng and Oat straw nourish the nervous system. Siberian Ginseng has a particularly rejuvenating effect upon the adrenal glands, and will also act as a tonic during the weeks of convalescence.
How Milk Thistle Works
Milk Thistle seeds contain the flavonoids silibinin, siliclianin and silicristin, collectively known as silymarin. One of the most active constituents is silibinin, which improves the function of the liver and kidneys and prevents and repairs damage. (Within the liver it specifically modulates the CDKI-CDK-cyclin cascade.)
- Silymarin inhibits the factors responsible for liver damage and stimulates the growth of new liver cells to replace injured ones. Toxins that attack and remain within the liver produce or act as free radicals which are highly reactive molecules that damage other molecules, including those in cells. Silymarin prevents free radical damage by acting as an antioxidant, one that is even more powerful than vitamin E.
- Silymarin has been shown to increase the glutathione content of the liver. Glutathione takes up and gives off hydrogen, and is fundamentally important in cellular respiration. The effect of silymarin on the system is to pump out poisons; therefore, by increasing the glutathione content of the liver, it gives it an increased capacity for the process of detoxification.
- The liver can also be damaged by the action of leukotrienes. Leukotrienes are compounds produced by the transfer of an oxygen molecule to polyunsaturated fatty acids, a reaction caused by the enzyme lipoxygenase. Silymarin is a potent inhibitor of this enzyme and fights against leukotriene formation. Silymarin may also be an important factor in the treatment of psoriasis, because of the cause of this condition is over-production of leukotrienes. Psoriasis has also been shown to be linked to a high level of circulating endotoxins such as those found in gut bacteria. If the level of endotoxins or toxins increases until the liver is overwhelmed, or if the liver's ability to filter and detoxify is inhibited, then the existing psoriasis becomes worse.
- Silymarin has the ability to stimulate protein synthesis, an action that results in an increase in the production of new liver cells to replace old ones, but which does not increase malignant cells, thus exerting both protective and restorative influences.
- Another protective role played by silymarin involves the way in which toxins are cycled continuously between the gastrointestinal tract and the liver, which usually cannot avoid causing some liver damage. Silymarin interrupts that cycle. More than 90 per cent of the silymarin that is absorbed through the intestines ends up in the liver. From there it is passed into the intestines, along with bile and then as much as 50 per cent is reabsorbed through the intestines. Hardly any silymarin reaches the bloodstream and only 5–7 per cent is eliminated in urine. It is repeatedly recycled through the intestines and liver, moving from blood plasma to bile and concentrating its beneficial effects in the liver cells. These cells are protected from damage by circulating toxins and so can act as centres for the generation of new cells. Eventually, complete restoration of the liver is possible. Silymarin has proved to be particularly effective in protecting against liver damage that is caused by alcohol and chemical toxins.
- Milk Thistle's stimulating, decongestive action is also useful in the treatment of problems of the kidneys, lungs, heart, bladder and uterus. It also ensures a sense of well-being and good health.
- Reverses alcohol damage.
- Speeds recovery in viral and alcohol-induced hepatitis.
- Slows progression of cirrhosis and extends life expectancy.
- Protects against side effects of some pharmaceutical drugs.
- Improves liver function in cases of chemical poisoning.
- Helps reverse liver damage.
- Improves circulation.
- Promotes bowel movement via an increase in blood flow.
- Improves kidney function and urination.
- Clears the skin of rashes and some skin diseases.
- Assists in countering the pain and discomfort of menstrual and premenstrual problems.
- Helps any ‘oestrogen dominant’ situation where the need to remove these unwanted excesses is important, e.g. endometriosis, fibroids, etc.
Milk Thistle extract is absorbed into the blood very quickly and reaches its full potential one hour after it has been taken.
Depending upon the type and severity of a patient's disease, a course of treatment that includes Milk Thistle may start to show significant results in as little as seven days; but in severe cases of cirrhosis and chronic hepatitis, full remission may take two years.
In cases of general debility and biliousness, an improvement will be felt after a week to ten days. If the skin has a jaundiced hue, this will eventually disappear.
Two small endocrine glands, one located above each kidney. They consist of a cortex, which secretes corticosteroid hormones such as cortisol, and a medulla, which secretes adrenaline.
Substances found particularly in high-chlorophyll foods that protect the cells from free radicals (damaging molecules) and reduce the risk of some serious diseases.
The smallest blood vessels.
A fat-like substance in the blood and most tissue, especially nervous tissue. Cholesterol is synthesised from acetate, mainly in the liver.
A substance that increase the volume of urine produced by promoting excretion of salts and water from the kidneys.
DNA is an abbreviation for deoxyribonucleic acid, a nucleic acid that is the main constituent of chromosomes. It can replicate itself and is responsible for transmitting genetic information.
A toxin produced within a microorganism and released upon destruction of the cell in which it is produced.
Compounds in plants that are responsible for a wide range of actions that include reducing inflammation, antioxidant activity and fighting fungus.
Highly reactive particles that damage cell membranes, DNA, and other cellular structures.
Capacity and function of the body to fend off foreign bodies, such as fungi, viruses, and bacteria, and/or disarm and eject them.
Molecules released into the synapse (the gap between a nerve cell and another cell) in response to a nerve impulse and that carry messages between cells.
An immune cell that engulfs and digests cells, microorganisms, or other foreign bodies in the bloodstream and tissues.
One of a group of compound lipids, consisting of phosphoric acid, fatty acids, and a nitrogenous base, forming an important part of cell membranes.
Hormone-like compounds made from fatty acids. They affect the nervous system, blood vessels, and metabolism.
A chronic skin disease in which scaly pink patches form primarily on the scalp, knees and elbows, but also on other parts of the body.
Plant medicine prepared by soaking herbs in alcohol and water.
A poisonous substance.