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Medicinal herbs

  • Lack of energy is a constant theme in the lives of countless Americans. For many, tiredness is so routine that they accept it as a natural state. Family and work by themselves are exhausting; unexpected demands or a restless night can deplete the remaining energy reserves. What is to be done? The American answer is caffeine. Pick your flavor: coffee (then more coffee), energy drinks (which flavor and how tall?), sodas (nothing beats caffeine plus sugar!) and the list goes on. The idea is that, if the metabolism is flagging whip it harder or, better yet, throw in a quick burst of energy from a simple carbohydrate. Caffeinate, crash, repeat (perhaps several times throughout the day), then start over the next morning.

    And start over we do. Ninety percent of all American adults ingest caffeine daily. It is the go-to stimulant of choice, so much so that for a while Wrigley was producing eight stick chewing gum packs each stick of which contained as much caffeine as half a cup of coffee. To be sure, it is not as if caffeine has no benefits. After all, people consume caffeine mostly to improve productivity and related outcomes, not for pleasure. But what if the lack of energy is really just the body's response to a lack of rest (sound sleep usually is an early casualty of too much caffeine) and to a failure to recover from demands placed on it day in and day out? Under such circumstances, the daily caffeine fix is always needed and creates the conditions of its own demand along with downsides. Fortunately, it is possible to get off this merry-go-round.

    Controlling Caffeine
    Researchers have often wondered why it is that tea, despite its caffeine content, tends to relax individuals without making them drowsy. Similarly, those engaging in meditation practices may drink tea to dispel mental sluggishness and yet not become mentally agitated, as is typical with the consumption of too much coffee. Black and green teas give somewhat different answers. Black tea, for instance, contains one or more compounds that open up the peripheral circulation and also reduce blood levels of cortisol, the stress hormone. Likewise, blood platelet activation, which is linked to blood clotting and to the risk of heart attack, was lower in the tea drinkers in a clinical trial and this group reported a greater degree of relaxation in the recovery period after a stressful task.1 This is good news for the 65 percent of adult Americans who suffer from daily stress. L-Theanine, found in green and oolong teas, is more complicated. In one trial in which caffeine (250 milligrams) increased self-rated alertness along with jitteriness and blood pressure, theanine (200 milligrams) antagonized the effect of caffeine on blood pressure, but did not significantly affect jitteriness, alertness or other aspects of mood.2 At a lower level of caffeine consumption (150 milligram), theanine (250 milligrams) actually further improved the normal cognitive benefits of caffeine.3 Affects on stress per se also are found with theanine, with the degree of benefit depending on conditions and individuals.

    Various tests have demonstrated the anti-stress effects of L-theanine. One of the more revealing of these experiments examined brain wave patterns after the ingestion of theanine. This research built on the knowledge that humans produce specific patterns of electrical pulses on the surface of the brain that mirror brain states. The four primary wave patterns are known as the alpha, beta, delta and theta (a, b, d and q) brain waves, representing, respectively, 1) relaxed wakefulness, 2) excitation, 3) sound sleep, and dozing sleep.4

    In one experiment, 50 women volunteers (aged 18–22 years old) were divided into high-anxiety and low-anxiety groups. Each group was given either 50 or 200 mg theanine in water once a week. Their brain waves were measured during the 60 minutes after ingestion. The measurements were repeated twice during a two-month test period. The results were a marked increase in a-waves starting roughly 40 minutes after ingestion. Researchers concluded that theanine rapidly enters the system when ingested and that it heightens the index of the brain wave that is known to be linked to a state of relaxed wakefulness. Researchers also have explored whether the response to theanine might be influenced by the level of anxiety found in test subjects. As might be expected, the greater degree of change is found in those manifesting high anxiety.

    Theanine appears to protect against certain so-called "excitotoxins." It modulates the motor-stimulation associated with caffeine and it inhibits some of the actions of norepinephrine in the central nervous system, for instance. In tests with gerbils, theanine protected against the destruction of neurons induced ischemia, a condition that can lead to a rapid increase in glutamate in neurons and result in the death of these cells. Theanine taken in the evening may support improved sleep quality not by sedation, but through anxiolysis.5 The other herbs mentioned below also tend to improve sleep quality at least in part through the same mechanism.

    Saffron for Replacing Jitters with Emotional Balance
    Although small amounts of caffeine, meaning usually less than 400 milligrams per day, for the vast preponderance of individuals provides mostly an upside with little downside, excessive caffeine can lead to anxiety, physical and emotional "jitters," as well as insomnia. For many, black, oolong and green teas are more gentle alternatives to the concentrated caffeine of coffee, yet coffee is a preferred beverage for many. Moreover, caffeine is added to so many other pick-me-ups that individuals often are unaware of how much they are consuming throughout the day. Several herbs and spices are useful remedies to this excess. Saffron is one of these.

    Saffron is far more than merely a spice that gives color to rice and paella along with a distinctive aromatic signature. Crocins are the source of saffron's coloring properties, whereas its aromatic aspects come from picrocrocins and safranal. Medical texts from ancient Egypt, Persia and the Roman Empire attest to healing properties, including pain relief and calming effects. Similarly, Chinese and Indian healing systems ascribe these and more benefits to saffron. Other healing aspects include the treatment of coughs, better movement of nutrients into tissues and aphrodisiac qualities.

    At least eleven clinical studies have evaluated saffron for its impact on aspects of emotional balance, such as anxiety and depression. In comparative clinical trials, saffron intake after one or two weeks has proven to be comparable in efficacy to the drugs fluoxetine and imipramine. The mechanism of action seems to be the regulation of neurotransmitters.6 Other conditions that have been explored clinically with saffron include erectile dysfunction, vision, Alzheimer's disease and cosmetic benefits. In general, it is thought that there is a complementary action from more than twenty-five active compounds in saffron to yield the demonstrated clinical effects. One special extract that has been extensively clinically tested gives benefits when ingested at the level of 30 milligrams per day.

    Lemon Balm's Calming Effects, Sleep Benefits
    Another useful traditional herb is lemon balm (Melissa officinalis L.). Since the 19th Century, it has been recognized as being soothing during stress and anxiety. Lemon balm contains hydroxycinnamic and rosmarinic acids. Studies have shown that lemon balm consumption increases sleep quality, reduces stress and improves mood.7 Clinical trials have demonstrated the effects of lemon balm extract on cognitive health. Lemon balm improves cognitive performance by enhancing memory and accelerating the visual information processing.8,9 One high quality and tested extract is recommended at an intake level of 600 milligrams per day.

    Blue Dogbane Is a Bane for Stress
    Apocynum venetum L., commonly known as Luobuma in China, is a traditional and popular Chinese herb with a long history of use as a medicine and tea, both in Chinese and Uygur medicine. In fact, Apocynum venetum L. is mentioned in the ancient Dun Huang Manuscripts (written in the 5th to early 11th centuries A.D.) as a powerful longevity tonic. It especially is useful in cases of hypertension and anxiety.10 Among its other notable benefits is support for sleep. According to the official Chinese Pharmacopoeia, the herb calms the liver, soothes the nerves, treats palpitations and improves insomnia. As a tea in China, it is used especially for the elderly as a sleep aid and to reduce high blood pressure. Indeed, a commercial Luoboma "antihypertensive tea" is available commercially in the western province of China. Care should be taken to not confuse it with Indian Hemp (I), Apocynum androsaemifolium, poacynum pictum, I, or the blue dogbane native to Texas. Chinese White and Pink Dogbanes are inferior substitutes often presented as the same plant.

    Anxiety afflicts more than forty million Americans, hence is hardly a minor issue. As already explored above, caffeine and "energy" drinks aggravate anxiety, jitteriness and blood pressure. The exact mechanisms of blue dogbane's action, which likely are multiple, only partially have been elucidated. For instance, the herb inhibits superoxide generated from both the NADPH oxidase and the xanthine/xanthine oxidase systems in the arteries. The upshot of these actions is that there is more nitric oxide (NO) available locally to relax the vessels.11 Rather than taking multiple grams of L-arginine to provide a building block precursor for the production NO, just a little bit of this herb prevents the excessive destruction of NO and achieves the same benefit. The vasculature dilation effects of the blue dogbane extract, including in the brain, can be considerable. The benefits for relaxation, cortisol and stress reduction are significant. Clinical work indicates that the extract induces deeper sleep, meaning that it makes sleep more restful.12

    An interesting finding is that Apocynum venetum L. is a particularly rich source of isoquercitrin, the more active and much better absorbed form of the antioxidant quercetin. Some research suggests that Apocynum venetum L. is a safe alternative to St. John's Wort. Suggested consumption of the extract depends on its quality and the condition in mind; 50–150 milligrams represents typically suggested dosages.12

    Southern Ginseng
    Most Westerners have heard of ginseng and think that the Chinese name applies to only one species. However, in fact there are various "ginsengs" in Chinese medicine, each displaying particular benefits. Gynostemma pentaphyllum is "southern ginseng"; it also is called jiaogulan. It is considered to have powerful antioxidant and adaptogenic effects purported to increase longevity.13 The plant belongs to a family that includes cucumbers, gourds, and melons—its fruit is a small purple inedible gourd. It is little known in traditional Chinese medicine (TCM) because TCM is largely based on the dried materials that could be transported to the Imperial Court of the Chinese Emperors in Beijing. Research indicates significant effects of southern ginseng in the areas of blood glucose, improved insulin sensitivity, improved HbA1c (indicating improved glucose control in diabetics and reduced glycation) as well as other benefits.14

    Although local Chinese traditions long have reported adaptogenic effects, the impact of jiaogulan on stress and related conditions only recently has been explored by Western allopathic research. Nevertheless, a body of animal trials currently backs traditional uses to support human resilience to physical and mental challenges. For instance, a 2012 paper reports that oral administration of the ethanol extract of Gynostemma pentaphyllum can increase host defense in immunocompromised situations such as stress-induced immunosuppression.15,16 A report from the next year indicates that there are anxiolytic effects of an herbal ethanol extract from Gynostemma pentaphyllum in mice after exposure to chronic stress.17 In yet another model of chronic stress and related anxiety disorders in mice, gypenosides, proposed active ingredients in the herb, improved stress-induced anxiety disorders by modulating brain dopamine and serotonin activities and corticosterone levels.18 (Corticosterone in mice plays the same role as cortisol in humans.) Finally, a recent randomized, double-blind, placebo-controlled clinical trial lasting 12 weeks demonstrated that an extract of Gynostemma pentaphyllum led to significant decreases in total abdominal fat area, body weight, body fat mass, percent body fat, and body mass index. (BMI).19 It is likely that more than one mechanism of action was important in bringing about these clinical results.

    Do not forget magnesium! An estimated 68 percent of Americans do not consume the recommended daily allowance for magnesium. Some attribute this to modern dietary patterns, such as a failure to consume green vegetables and less refined grains. Others have observed that reduced magnesium levels can be attributed to food refining, processing and the use of industrial fertilizers, which typically lack magnesium. Magnesium deficiency has been associated with poor sleep quality, muscle tension and anxiety. Raising tissue levels with oral supplementation of magnesium may promote more restful sleep and relaxation. Preferred forms include magnesium glycerophosphate, magnesium malate and magnesium threonate. Each of these forms exhibits special characteristics based on its ligand. Better results with magnesium supplementation are realized with chronic usage to build up tissue stores.

    Too often, the demand for more energy really is just a symptom of inadequate rest and poor quality sleep. The majority of adults is chronically stressed and sleep deprived. Good sleep affects alertness, energy, creativity, indeed, mental and physical performance and productivity in general. The common solution to being tired and under-performing is to consume caffeine in the form of coffee and energy drinks. There are alternatives, however, to the "caffeinate, crash, repeat" model of daily existence. Some of these alternatives support the positive effects of caffeine while mitigating the side effects. Others moderate jitteriness and "wired" effects of stimulants by reducing the stress hormone release found with too much stimulation. A common benefit of this approach is to improve the ability to sleep without forcing slumber and to make the time spent sleeping more restful.


    1. Steptoe A, Gibson EL, Vuononvirta R, Williams ED, Hamer M, Rycroft JA, Erusalimsky JD, Wardle J. The effects of tea on psychophysiological stress responsivity and post-stress recovery: a randomised double-blind trial. Psychopharmacology (Berl). 2007 Jan;190(1):81-9. Epub 2006 Sep 30. Erratum in: Psychopharmacology (Berl). 2007 Jan;190(1):91.
    2. Rogers PJ, Smith JE, Heatherley SV, Pleydell-Pearce CW. Time for tea: mood, blood pressure and cognitive performance effects of caffeine and theanine administered alone and together. Psychopharmacology (Berl). 2008 Jan;195(4):569-77.
    3. Haskell CF, Kennedy DO, Milne AL, Wesnes KA, Scholey AB. The effects of L-theanine, caffeine and their combination on cognition and mood. Biol Psychol. 2008 Feb;77(2):113-22.
    4. Juneja LR, Chu D-C, Okubo T, Nagato Y, Yokogoshi H. L-Theanine––a unique amino acid of green tea and its relaxation effect in humans. Trends in Food Science & Technology 1999;10:199-204.
    5. Rao TP, Ozeki M, Juneja LR. In Search of a Safe Natural Sleep Aid. J Am Coll Nutr. 2015;34(5):436-47.
    7. Cases J, Ibarra A, Feuillere N, Roller M, Sukkar S. Pilot trial of Melissa officinalis L. leaf extract in the treatment of volunteers suffering from mild-to-moderate anxiety disorders and sleep disturbances. Mediterranean journal of nutrition and metabolism. 2011; 4(3): 211-8.1.
    8. Scholey A, Gibbs A, Neale C, et al. Investigation of a Melissa officinalis special extract on Cognition II: Human study - Lemon balm extract administered in confectionary bars. Agro FOOD Industry Hi Tech2015; 26(2): 12-4.
    9. Kennedy D, Wake G, Savelev S, et al. Modulation of mood and cognitive performance following acute administration of single doses of Melissa officinalis (Lemon balm) with human CNS nicotinic and muscarinic receptor-binding properties. Neuropsychopharmacology 2003; 28(10): 1871-81.
    10. Xie W, Zhang X, Wang T, Hu J. Botany, traditional uses, phytochemistry and pharmacology of Apocynum venetum L. (Luobuma): A review. J Ethnopharmacol. 2012 May 7;141(1):1-8.
    11. Lau YS, Ling WC, Murugan D, Kwan CY, Mustafa MR. Endothelium-Dependent Relaxation Effect of Apocynum venetum Leaf Extract via Src/PI3K/Akt Signalling Pathway. Nutrients. 2015 Jun 30;7(7):5239-53.
    12. Yamatsu A, Yamashita Y, Maru I, Yang J, Tatsuzaki J, Kim M. The Improvement of Sleep by Oral Intake of GABA and Apocynum venetum Leaf Extract. J Nutr Sci Vitaminol (Tokyo). 2015;61(2):182-7.
    13. Blumert, Michael; Jialiu Liu. Jiaogulan: China's "Immortality" Herb. (2003: Badger, CA: Torchlight Publishing.)
    15. Im SA, Choi HS, Choi SO, Kim KH, Lee S, Hwang BY, Lee MK, Lee CK. Restoration of electric footshock-induced immunosuppression in mice by Gynostemma pentaphyllum components. Molecules. 2012 Jun 25;17(7):7695-708.
    16. Shang X, Chao Y, Zhang Y, Lu C, Xu C, Niu W. Immunomodulatory and Antioxidant Effects of Polysaccharides from Gynostemma pentaphyllum Makino in Immunosuppressed Mice. Molecules. 2016 Aug 19;21(8).
    17. Choi HS, Zhao TT, Shin KS, Kim SH, Hwang BY, Lee CK, Lee MK. Anxiolytic effects of herbal ethanol extract from Gynostemma pentaphyllum in mice after exposure to chronic stress. Molecules. 2013 Apr 12;18(4):4342-56.
    18. Zhao TT, Shin KS, Choi HS, Lee MK. Ameliorating effects of gypenosides on chronic stress-induced anxiety disorders in mice. BMC Complement Altern Med. 2015 Sep 14;15:323.
    19. Park SH, Huh TL, Kim SY, Oh MR, Tirupathi Pichiah PB, Chae SW, Cha YS. Antiobesity effect of Gynostemma pentaphyllum extract (actiponin):
    20. a randomized, double-blind, placebo-controlled trial. Obesity (Silver Spring). 2014 Jan;22(1):63-71.
  • Alfalfa

    Common Uses: allergies, arthritis, cognitive disorder, cancer and urinary disorders.

    Alfalfa is purported to be one of the best herbal therapies for arthritis. It also possesses cancer-preventing properties by inactivating chemicals that can cause cancer. It is often fed to animals that need to gain weight.

    The vitamin K content of alfalfa makes it valuable in pets with bleeding disorders. Conversely, excess doses might interfere with blood clotting due to the coumarin (an anticoagulant) content in alfalfa.

    Alfalfa can make urine alkaline and is useful in those bladder conditions where a more alkaline urine is needed (likewise, it should not be used in pets whose medical conditions require an acid urine).

    Due to the large content of nutrients, many doctors recommend it for pets that require increased mental nutrition (older pets, especially those with cognitive disorder).

    Safety Issues
    Alfalfa is generally regarded safe. The seeds can cause blood disorders due to L-canavanine and seeds should be avoided.

    Animals sensitive to pollen may be sensitive to fresh alfalfa.

    Aminocaproic Acid (ACA)

    Common use: degenerative myelopathy. Aminocaproic acid works by inhibiting the process of fibrinolysis (the breakdown of fibrin, a protein needed for proper blood clotting) and can reverse states that are associated with excessive fibrinolysis. Degenerative myelopathy is theorized to be caused by an autoimmune response (possibly from over-vaccinating dogs) attacking the nervous system of dogs, which leads to progressive neural tissue damage. Since this is an autoimmune response, immune complexes circulate in the blood, leading to endothelial cell damage in the blood vessels of the central nervous system. This causes fibrin to be deposited around blood vessels. When the fibrin degrades, inflammatory cells are stimulated to migrate into the lesions, which leads to tissue damage. It is possible ACA may limit or stop this process.

    Aminocaproic acid is made in a 250 mg/ml oral solution. This can be mixed with chicken broth, using 2 ml of the drug and 1 ml of chicken broth. The recommended dosage is 500 mg (3 ml of the above combination) given three times a day with or without food. ACA should be stored at room temperature with the lid tightly closed.


    Common uses: liver disease, heart disease, and cancer. Arginine is an essential amino acid found in many foods. It plays a role in several bio-chemical processes in the body, including cell division, wound healing, immune functions, hormone secretion, and the removal of ammonia from the body. Arginine is also involved in the formation of nitric oxide, which relaxes blood vessels.

    Doses of 500 mg to 3000 mg per day are recommended.

    Safety Issues
    Since arginine is an amino acid, supplementation is believed to be safe. Maximum safe doses have not however, been established.


    Common uses: cancer, infections, kidney disease, and hyperthyroidism in cats.

    Astragalus is used to strengthen the immune system and acts as an anti-inflammatory. Many doctors prescribe it for pets with various infections and chronic illnesses. It can be used to help the body recover from long-term steroid therapy and for pets with kidney disease as it improves kidney circulation.

    Safety Issues
    The medicinal herb Astragalus membranaceous is safe; many other species are toxic. For hyper-immune disorders (autoimmune diseases, diabetes), and disorders with diminished immune systems with low white blood cell counts (feline leukemia and immunodeficiency diseases), it may be wise to avoid this herb, as astragalus is used for immune stimulation. It is best used early in the course of the disease to stimulate the immune system. Do not use to treat hypothyroidism.

  • Culinary herbs seldom began their human histories as mere flavorings. Indeed, the kitchen herb and spice rack could reasonably be dubbed the kitchen medicine chest and several useful books have done just that. Oregano is a good example of a culinary herb that leads a double life. In much of the world, this plant continues to be used not just to flavor and preserve food, but also to disinfect surfaces and wounds, to calm the stomach, and much more. For some of these purposes, oregano extracts may still be as good or better than many of the modern alternatives. In other words, the health benefits of oregano are not only "traditional" or "folk remedies."

    In recent years, oregano has been surprisingly well studied. Harry Preuss of Georgetown University Medical Center, for instance, over the last decade has published five studies on oregano and other essential oils with results that are impressive. For uses as diverse as from antibiotics to weight loss, oregano and its constituent compounds are attracting new interest in an old remedy.

    Snapshot of Oregano

    Oregano (Origanum vulgare) is in the same family as rosemary, thyme and the mints. Also called "wild" or "winter" marjoram, it is not to be confused with the related "sweet" marjoram. A further distinction often is made in the health food industry between the oregano cultivated for culinary uses and the species that grow wild, particularly in the Eastern Mediterranean. The latter have a much stronger flavor and aroma reflecting their higher content of certain essential oils.

    Constituents of oregano vary with the species, the growing area and the season. The chief active constituents of oregano are a volatile oil known as carvacrol along with the related compound thymol, which is more characteristic of the herb thyme. Also found are the precursor molecule p-cymene and smaller amounts of a variety of other phenolic compounds. Most of the volatile compounds found in oregano are terpenes. Although it might seem to be a foreign term from chemistry, almost everyone is familiar with one or more terpenes—probably the best known terpene is limonene, the highly aromatic compound found in the peel of oranges and the chief component of orange oil.

    A number of the most ancient employments for oregano remain common. Uses attributed to Hippocrates and the Greek medical tradition include as an antiseptic, a cure for stomach complaints and as a solution to respiratory ailments. Other uses sometimes suggested include rheumatoid arthritis, urinary tract infections, headaches, convulsions and fatigue (the last being common in 19th Century materia medica manuals). A favored use both in the past and today is for parasites.1 The essential oil exhibits diuretic, expectorant and antispasmodic properties as well as a stimulant effect on bile production.2

    Modern Experimental Science Takes a Look at Oregano

    Much of the focus of contemporary oregano research has been on its benefits against fungal and bacterial infections. Some eighty percent of all antibiotics produced in the US are fed to animals, a seriously bad practice that creates reservoirs of resistant bacteria that then are transmitted to humans via food and other vectors.

    In the first of several studies, researchers at Georgetown University Medical Center examined a number of volatile aromatic oils for their benefits.3 Oregano oil, which today primarily is used as a food flavoring agent, was hypothesized to possess a broad spectrum of in vitro antimicrobial activities attributable to the high content of phenolic derivatives such as carvacrol and thymol. In a study published in 2001, the antifungal properties of oregano oil were examined both in vitro and in vivo using the yeast Candida albicans as the exemplar fungal model. In an animal model of systemic candidiasis using mice, consumption of oregano oil supplied in olive oil led to 80% survival at 30 days versus none in the animals fed only olive oil. Carvacrol, the major constituent of the oil, was similarly effective, yet visual observation found that the mice consuming the oregano oil presented a cosmetically superior clinical appearance. This trial showed that oregano oil warrants further examination for possible benefits in pathogenic fungal infections.

    A second trial explored the benefits of oregano oil and the coconut oil fraction monolaurin against one of the more common bacterial infective agents, Staphylococcus aureus.4 As before, both in vitro and in vivo tests were carried out. In vitro, oregano oil was the most successful of the essential oils tested. In mice, systemic infection with S. aureus is routinely and rapidly fatal. This particular trial found that all 14 mice in the untreated arm of the study died within a one week period. Of the oregano oil treated mice, six of fourteen were still alive at 30 days. This compared favorably with the survival rates of those receiving daily vancomycin (7/14) and monolaurin (4/8). Over 60% of mice survived when receiving a daily combination of oregano oil and monolaurin (5/8). This trial therefore demonstrated that oregano oil, either alone or in combination with monolaurin, warrants further examination for possible use for prevention and therapy of Staphylococcus aureus infections. Numerous studies, in fact, have been undertaken since this one and have demonstrated, for instance, activity against methicillin-resistant staphylococci.5 In a world of increasing resistance to antibiotics, this is significant.

    Needless to say, staphylococci are not the only bacterial pathogens against which new active agents are required. A third test conducted at Dr. Preuss' laboratory examined the efficacy in vitro of oregano and several other essential oils as well as monolaurin against a variety of gram-positive and gram-negative bacteria. Oregano oil proved active against all the tested pathogens except B. anthracis Sterne.6

    The successful use of oregano oil against parasitic infections has been mentioned already.

    New Research Directions for Oregano

    Two interesting developments in modern research may break new ground for uses of oregano oil. The first involves insulin metabolism. Researchers in 2005 examined the ability of various combinations of essential oils such as fenugreek, cinnamon, cumin, oregano, etc. to enhance insulin sensitivity. As a first approximation, they examined the effects of these natural products on Zucker fatty rats, a model of obesity and insulin resistance, and spontaneously hypertensive rats, a model of genetic hypertension. The ability to alter systolic blood pressure (the upper figure) in rat models is the most sensitive early index of insulin sensitivity. In this particular trial, various combinations of essential oils lowered blood pressure in both rat species, suggesting improved insulin sensitivity.7

    The story does not end with blood pressure data. Relatedly, a mouse study found that carvacrol appears to inhibit visceral adipogenesis (the creation of new fat cells in belly fat tissue) and it also attenuates the production of pro-inflammatory cytokines in these tissues.8 Work in another model, this one with induced edema in the paws, demonstrated anti-inflammatory and anti-ulcer protections, as well.9

    Finally, there is information emerging regarding oregano's protection against prostate cancer. According to Dr. Supriya Bavadekar, PhD, RPh, Assistant Professor of Pharmacology at Long Island University's Arnold & Marie Schwartz College of Pharmacy and Health Sciences, the lead scientist for work presented at a conference in 2012, "Some researchers have previously shown that eating pizza may cut down cancer risk. This effect has been mostly attributed to lycopene, a substance found in tomato sauce, but we now feel that even the oregano seasoning may play a role."10

    Safety and Usage of Oregano

    Oregano and oregano oil are generally considered as safe (GRAS). However, caveats do apply. Large amounts of either may irritate the gastrointestinal tract. Concentrated amounts taken internally especially should be avoided in pregnancy and lactation. Also, the essential oil can be an irritant not just to the gastrointestinal tract, but to the skin, hence topically the essential oil usually is applied only as part of a prepared ointment.

    For intestinal parasitic infection, an emulsified oil of oregano has been used in a dose of 200 mg three times daily for 6 weeks, but such treatments need to be overseen by an experienced physician. Traditionally for other purposes, a typical dose is one cup of tea made by steeping one heaping teaspoon of the dried leaf in 250 mL boiling water 10 minutes. Alternatively, 19th Century herbals and medical manuals suggested 2 - 5 drops / day of the essential oil taken on a sugar cube for gastrointestinal issues and as an aromatic stimulant.

    1. Force M, Sparks WS, Ronzio RA. Inhibition of enteric parasites by emulsified oil of oregano in vivo. Phytother Res 2000:14:213-4.
    2. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
    3. Manohar V, Ingram C, Gray J, Talpur NA, Echard BW, Bagchi D, Preuss HG. Antifungal activities of origanum oil against Candida albicans. Mol Cell Biochem. 2001 Dec;228(1-2):111-7.
    4. Preuss HG, Echard B, Dadgar A, Talpur N, Manohar V, Enig M, Bagchi D, Ingram C. Effects of Essential Oils and Monolaurin on Staphylococcus aureus: In Vitro and In Vivo Studies. Toxicol Mech Methods. 2005;15(4):279-85.
    5. Nostro A, Blanco AR, Cannatelli MA, Enea V, Flamini G, Morelli I, Sudano Roccaro A, Alonzo V. Susceptibility of methicillin-resistant staphylococci to oregano essential oil, carvacrol and thymol. FEMS Microbiol Lett. 2004 Jan 30;230(2):191-5.
    6. Preuss HG, Echard B, Enig M, Brook I, Elliott TB. Minimum inhibitory concentrations of herbal essential oils and monolaurin for gram-positive and gram-negative bacteria. Mol Cell Biochem. 2005 Apr;272(1-2):29-34.
    7. Talpur N, Echard B, Ingram C, Bagchi D, Preuss H. Effects of a novel formulation of essential oils on glucose-insulin metabolism in diabetic and hypertensive rats: a pilot study. Diabetes Obes Metab. 2005 Mar;7(2):193-9.
    8. Cho S, Choi Y, Park S, Park T. Carvacrol prevents diet-induced obesity by modulating gene expressions involved in adipogenesis and inflammation in mice fed with high-fat diet. J Nutr Biochem. 2012 Feb;23(2):192-201.
    9. Silva FV, Guimarães AG, Silva ER, Sousa-Neto BP, Machado FD, Quintans-Júnior LJ, Arcanjo DD, Oliveira FA, Oliveira RC. Anti-inflammatory and anti-ulcer activities of carvacrol, a monoterpene present in the essential oil of oregano. J Med Food. 2012 Nov;15(11):984-91.
    10. Federation of American Societies for Experimental Biology (FASEB). "Component of pizza seasoning herb oregano kills prostate cancer cells." ScienceDaily, 24 Apr. 2012. Web. 23 Jan. 2013.