Groupe I
1376 posts depuis
le 11/11/2006
De : monde
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Sites sur lesquels on peut trouver quelque information sur le trèfle rouge :
http://www.passeportsante.net/fr/Solutions/PlantesSupplements/Fiche.aspx?doc=trefle_rouge_ps
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-redclover.html
Je me permets de citer ce dernier site ( prudent mais honnête ) :
" Red clover (Trifolium pratense)
BackgroundReturn to top
Red clover is a legume, which like soy contains "phytoestrogens" (plant-based chemicals that are similar to estrogen, and may act in the body like estrogen or may actually block the effects of estrogen). Red clover was traditionally used to treat asthma, pertussis, cancer, and gout. In modern times, isoflavone extracts of red clover are most often used to treat menopausal symptoms, as an alternative hormone replacement therapy, for high cholesterol, or to prevent osteoporosis. However, at this time, there are no high-quality human studies supporting the use of red clover for any medical condition.
SynonymsReturn to top
Ackerklee (German), beebread, cow clover, genistein, isoflavone, isoflavone clover extract (ICE), meadow clover, phytoestrogen, Promensil®, purple clover, Rimostil®, Rotklee (German), trefle des pres (French), trefoil, trifolium pratense, Trinovin®, wild clover.
EvidenceReturn to top
These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.
Uses based on scientific evidence Grade*
Cardiovascular - blood flow
Red clover has been shown to improve the flow of blood through arteries and veins. However there is limited study in this area and more research is needed before a conclusion can be drawn. C
Diabetes
Red clover has been studied in patients with type 2 diabetes to determine potential benefits in diabetic complications such as high blood pressure and narrowing of the arteries and veins.Further research is needed before a recommendation can be made. C
High cholesterol
Red clover has not been clearly shown to have beneficial effects on blood cholesterol levels. Due to conflicting study results, further research is needed in this area before a recommendation can be made. C
Hormone replacement therapy (HRT)
Laboratory research suggests that red clover isoflavones have estrogen-like activity. However, there is no clear evidence that isoflavones share the possible benefits of estrogens (such as effects on bone density). In addition, hormone replacement therapy itself is a controversial topic, with recent research reporting that the potential harm may outweigh any benefits. C
Menopausal symptoms
Red clover isoflavones are proposed to reduce symptoms of menopause (such as hot flashes), and are popular for this use. Blood pressure and triglyceride levels may be lowered. However, most of the available human studies are poorly designed and short in duration (less than 12 weeks of treatment).As results of published studies conflict with each other, more research is needed before a clear conclusion can be drawn. C
Osteoporosis
It is not clear if red clover isoflavones have beneficial effects on bone density. Most studies of isoflavones in this area have looked at soy, which contains different amounts of isoflavones, as well as other non-isoflavone ingredients. More research is needed before a recommendation can be made. C
Prostate cancer
Red clover isoflavones may have estrogen-like properties in the body, and have been proposed as a possible therapy in prostate cancer and related hot flashes. Some isoflavones have also been shown in laboratory studies to have anti-cancer properties. Because there is no-well designed human research in this area, a recommendation cannot be made. C
Prostate enlargement (benign prostatic hypertrophy)
There is only limited study of red clover for benign prostatic hypertrophy. More research is needed before a firm conclusion can be drawn. C
*Key to grades
A: Strong scientific evidence for this use;
B: Good scientific evidence for this use;
C: Unclear scientific evidence for this use;
D: Fair scientific evidence against this use;
F: Strong scientific evidence against this use.
Grading rationale
Uses based on tradition or theory
The below uses are based on tradition or scientific theories. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.
Acne, AIDS, antibacterial, antioxidant, anti-spasm, appetite suppressant, arthritis, asthma, blood purification, breast cancer prevention, bronchitis, burns, cancer, cancer prevention, canker sores, cardiovascular disease, cognitive function, cough, chronic skin diseases, diuretic (increase urine flow), eczema, endocrine responsive cancer, gout, increasing HDL cholesterol, indigestion, mastalgia (breast pain), osteosarcoma, premenstrual syndrome, psoriasis, sexually transmitted diseases, skin ulcers/sores, sore eyes, tuberculosis, whooping cough (pertussis).
DosingReturn to top
The below doses are based on scientific research, publications, traditional use, or expert opinion. Many herbs and supplements have not been thoroughly tested, and safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients, even within the same brand. The below doses may not apply to all products. You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.
Adults (18 years and older)
Various doses of red clover isoflavones have been used to treat conditions. For instance, for benign prostatic hypertrophy, 40 milligrams of red clover isoflavones per day (Trinovin®) has been studied. For breast cancer prevention,a red clover-derived isoflavone tablet containing 26 milligrams biochanin A, 16 milligrams formononetin, 1 milligram genistein and 0.5 milligram of daidzein has been studied.
For cardiovascular disease, 86 milligrams per day for one month has been studied.For diabetes, 50 milligrams and 86 milligrams per day of red clover isoflavones per day have been studied for diabetic complications.For high cholesterol 28 to 86 milligrams of red clover isoflavones per day (Rimostil®), or 80 milligrams of red clover isoflavones per day (Promensil®) has been studied.For hormone replacement, 40 to 80 milligrams of red clover isoflavones per day (Promensil®) has been studied.
For menopausal symptoms 40 milligrams, 80 milligrams, or 160 milligrams of red clover isoflavones per day (Promensil®) has been studied. Rimostil® (57 milligrams of red clover) has also been used. For osteoporosis 40 milligrams of red clover isoflavones per day (Promensil®) has been studied.
Children (younger than 18 years)
There is not enough scientific evidence to recommend use of red clover in children.
SafetyReturn to top
The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.
Allergies
People with known allergies or reactions to products containing red clover or isoflavones should avoid taking red clover.
Side Effects and Warnings
A small number of human studies using red clover extracts have all reported good tolerance, without serious side effects after up to one year of treatment. In theory, based on the estrogen-like action of red clover seen in laboratory studies, side effects may include weight gain or breast tenderness, although these have not been reported clearly in humans. In theory, menstrual changes and increased uterus cell growth (endometrial hyperplasia) may also occur, although preliminary short-term studies (less than six months) have found no increases in uterus wall (endometrial) thickness with red clover. Red clover may affect hormonal levels of gonadotropin releasing hormone (GrH), follicle stimulating hormone (FSH), and leutinizing hormone (LH), although early research has not found significant change in FSH or LH levels.
In theory, red clover may increase the risk of bleeding. However, there are no reliable human reports of bleeding with red clover. Caution is advised in patients with bleeding disorders or taking drugs that may increase the risk of bleeding. Dosing adjustments may be necessary.
Red clover has been studied for lowering blood sugar with inconclusive results. Caution is warranted until further research is available.
Pregnancy and Breastfeeding
Red clover is not recommended during pregnancy and breastfeeding due to its estrogen-like activity. Red clover has been reported as a possible cause of infertility and abortion in grazing livestock.
InteractionsReturn to top
Most herbs and supplements have not been thoroughly tested for interactions with other herbs, supplements, drugs, or foods. The interactions listed below are based on reports in scientific publications, laboratory experiments, or traditional use. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy.
Interactions with Drugs
Based on laboratory studies, red clover may interfere with the way the liver processes some drugs using an enzyme called cytochrome P450 3A4. As a result, the levels of these drugs may be increased in the blood, and may cause increased effects or potentially serious adverse reactions. Patients using any medications should check the package insert and speak with a healthcare professional or pharmacist about possible interactions.
In theory, red clover may increase the risk of bleeding when taken with drugs that increase the risk of bleeding. Some examples include aspirin, anticoagulants ("blood thinners") such as warfarin (Coumadin®) or heparin, anti-platelet drugs such as clopidogrel (Plavix®), and non-steroidal anti-inflammatory drugs such as ibuprofen (Motrin®, Advil®) or naproxen (Naprosyn®, Aleve®). Because red clover contains estrogen-like chemicals, the effects of drugs with estrogen or estrogen-like properties may be altered, such as birth control pills or hormone replacement therapies like Premarin® and Provera®.
Red clover has been studied for lowering blood sugar with inconclusive results. Caution is warranted if you are diabetic or taking other medications that me lower blood sugar until further research is available.
In theory, red clover may interact with other estrogen containing medications. Red clover contains phytoestrogens, which are plant-based chemicals that are similar to estrogen, and may act in the body like estrogen or may actually block the effects of estrogen).
Interactions with Herbs and Dietary Supplements
Based on laboratory studies, red clover may interfere with the way the liver processes some drugs using an enzyme called cytochrome P450 3A4. As a result, red clover may cause the levels of other herbs or supplements to be too high in the blood. It may also alter the effects that other herbs or supplements possibly have on the P450 system.
In theory, red clover may increase the risk of bleeding when taken with herbs or supplements that increase the risk of bleeding. Multiple cases of bleeding have been reported with the use of Ginkgo biloba , fewer cases with garlic, and two cases with saw palmetto. Numerous other agents may theoretically increase the risk of bleeding, although this has not been proven in most cases.
Because red clover contains estrogen-like chemicals, the effects of other agents believed to have estrogen-like properties may be altered.
Red clover has been studied for lowering blood sugar with inconclusive results. Caution is warranted if you are diabetic or taking other herbs or supplements that may lower blood sugar until further research is available.
Methodology Return to top
This information is based on a professional level monograph edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com): Ernie-Paul Barrette, MD (Case Western Reserve School of Medicine); Ethan Basch, MD (Memorial Sloan-Kettering Cancer Center); Samuel Basch, MD (Mt. Sinai Medical Center, NY); Steve Bent, MD (University of California, San Francisco); Edzard Ernst, MD, PhD (University of Exeter); Sadaf Hashmi, MD, MPH (Johns Hopkins School of Hygiene and Public Health); Jamie Nelsen, PharmD (University of Rhode Island); Adrianne Rogers, MD (Boston University School of Medicine); David Sollars MAc, HMC (New England School of Acupuncture); Philippe Szapary, MD, MPH (University of Pennsylvania); Candy Tsourounis, Pharm D (University of California, San Francisco); Catherine Ulbricht, PharmD (Massachusetts General Hospital); Wendy Weissner, BA (Natural Standard Research Collaboration).
Methodology details
Selected references Return to top
1. Atkinson C, Compston JE, Robins SP, et al. The effects of isoflavone phytoestrogens on bone: preliminary results from a large randomized controlled trial. Endocr Soc Annu Meet Program 2000;82:196.
2. Atkinson C, Compston JE, Day NE, et al. The effects of phytoestrogen isoflavones on bone density in women: a double-blind, randomized, placebo-controlled trial. Am.J Clin.Nutr. 2004;79(2):326-333.
3. Atkinson C, Warren RM, Sala E,et al. Red-clover-derived isoflavones and mammographic breast density: a double-blind, randomized, placebo-controlled trial [ISRCTN42940165]. Breast Cancer Res. 2004;6(3):R170-R179.
4. Baber RJ, Templeman C, Morton T, et al. Randomized placebo-controlled trial of an isoflavone supplement and menopausal symptoms in women. Climacteric 1999;2:85-92.
5. Beck V, Unterrieder E, Krenn L, et al. Comparison of hormonal activity (estrogen, androgen and progestin) of standardized plant extracts for large scale use in hormone replacement therapy. J Steroid Biochem.Mol.Biol. 2003;84(2-3):259-268.
6. Howes J, Waring M, Huang L, et al. Long-term pharmacokinetics of an extract of isoflavones from red clover (Trifolium pratense). J Altern.Complement Med. 2002;8(2):135-142.
7. Howes JB, Sullivan D, Lai N, et al. The effects of dietary supplementation with isoflavones from red clover on the lipoprotein profiles of post menopausal women with mild to moderate hypercholesterolaemia. Atherosclerosis 2000;152(1):143-147.
8. Howes JB, Tran D, Brillante D, et al. Effects of dietary supplementation with isoflavones from red clover on ambulatory blood pressure and endothelial function in postmenopausal type 2 diabetes. Diabetes Obes.Metab 2003;5(5):325-332.
9. Rossouw JE, Anderson GL, Prentice RL, et al. Risks and benefits of estrogen plus progestin in healthy postmenopausal women: principal results From the Women's Health Initiative randomized controlled trial. JAMA 7-17-2002;288(3):321-333.
10. Nelson HD, Vesco KK, Haney E, et al. Nonhormonal therapies for menopausal hot flashes: systematic review and meta-analysis. JAMA. 2006 May 3;295(17):2057-71.
11. Teede HJ, McGrath BP, DeSilva L, et al. Isoflavones reduce arterial stiffness: a placebo-controlled study in men and postmenopausal women. Arterioscler.Thromb.Vasc.Biol. 6-1-2003;23(6):1066-1071.
12. Tice JA, Ettinger B, Ensrud K, et al. Phytoestrogen supplements for the treatment of hot flashes: the Isoflavone Clover Extract (ICE) Study: a randomized controlled trial. JAMA 7-9-2003;290(2):207-214.
December 01, 2006. "
Et j'en remets une couche :
" In theory, red clover may interact with other estrogen containing medications. Red clover contains phytoestrogens, which are plant-based chemicals that are similar to estrogen, and may act in the body like estrogen or may actually block the effects of estrogen"
Conclusion : ...
Enfin, pour donner une nouvelle toute petite idée des enjeux :
" Le laboratoire Christian Doppler pour la biotechnologie des récepteurs étudiera et évaluera l'efficacité des herbes et des extraits de plantes médicinales.
Le trèfle vert (Trifolium pratense), l'actée à grappes (Cimicifuga racemosa) et le soja seront plus particulièrement ciblés, ces plantes pouvant constituer une alternative aux traitements des dérèglements du métabolisme et aux traitements de prévention des cancers hormono-dépendants. Elles renferment effectivement des substances capables de mimer les hormones du corps humain, sexuelles ou stéroïdes.
L'équipe d'Alois Jungbauer, professeur à l'Université agronomique de Vienne, cherchera à isoler ces substances actives, afin de décrypter peu à peu les modes d'action des extraits de plantes en circulation. Car employer ces extraits sur la base de connaissances empiriques, à l'instar de guérisseurs, ne suffit plus : les mécanismes sous-jacents peuvent et doivent être compris, quand bien même ces extraits seraient des mélanges complexes. Les préparations à base de trèfle rouge peuvent ainsi contenir 300 substances bioactives, dont une cinquantaine influeront le système endocrinien.
Alois Jungbauer s'intéressera d'abord aux effets des polyphénols naturels sur les récepteurs hormonaux : récepteurs aux oestrogènes, à la progestérone, à l'androgène et à l'arylhydrocarbone.
Le nouveau laboratoire disposera pour cela d'un budget de 400 000 euros/an, issu pour moitié de l'entreprise pharmaceutique Melbrosin, à l'origine de produits parapharmaceutiques tirés de substances naturelles (Menoflavon, Melprosia, Melpromen, Androflavon...).
De fait, les laboratoires rattachés à la société de recherche appliquée Christian Doppler (CDG) sont cofinancés par le public et le privé. Résultat d'une collaboration entre des chercheurs et une ou plusieurs entreprises, ils sont créés pour sept ans et soumis à évaluation à mi-parcours.
Contacts :
- Alois Jungbauer, Universitat für Bodenkultur, Muthgasse 18, A-1190 Wien - tel : +43 1 36006 6226, fax : +43 1 3697615, alois.jungbauer(a)boku.ac.at
- Christian Doppler Forschungsgesellschaft, Weyringergasse 33/3, A-1040 Wien -
http://www.melbrosin.at
Sources : CDG, 01/07/2005, APA, 13/07/2005
Sources : Ambassade de France en Autriche- Adit" cf http://www.info-veille-biotech.com/index.php?lettre=70 |
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