Does drinking soy milk every day lead to excessively high estrogen levels? Why are plant ingredients such as red clover (Rotklee) and hops (Hopfen) commonly found in German menopause health products? The key is: phytoestrogens are not the same as human estrogen, and food is not the same as concentrated herbal supplements.
1. What are the phytoestrogens in soy milk?
Soybeans (Soja) contain soy isoflavones, mainly genistein and daidzein. They are phytoestrogens (Phytoestrogens / Phytoöstrogene) that can interact with estrogen receptors, but their activity and receptor preferences differ from human estrogen. It cannot be directly inferred that "drinking soy milk = supplementing human estrogen." Sugar-free soy milk is also a source of plant-based protein.
2. What do 2025 studies say?
A systematic review and meta-analysis published in Advances in Nutrition in 2025 synthesized 40 randomized controlled trials involving 3,285 postmenopausal women. The study found no statistically significant increase in blood estradiol or endometrial thickness from soy isoflavone intake. This supports the view that "just because soybeans contain phytoestrogens, it does not mean they will cause excessively high estrogen levels."
Interpretation reminder: The study participants were mainly postmenopausal women, and the isoflavone doses used in the trials may not be the same as a daily cup of soy milk. Individual circumstances may also vary, so it can serve as a reference for daily dietary choices.
3. Common representative phytoestrogens in Germany
1. Soybeans Soja / Soy
The main components are isoflavones. Daily soy products and high-concentration isoflavone capsules should be evaluated separately. Moderate intake of soy products in a regular diet does not need to be completely avoided just because of the words "phytoestrogens."
2. Red clover Rotklee / Red Clover
Red clover (Trifolium pratense) contains isoflavones such as biochanin A and formononetin and is a common plant raw material in German nutritional supplements for menopause. Some products claim to support hot flashes and other menopausal discomforts, and related research is continuously accumulating; it belongs to the nutritional supplement route and is a different choice from hormone therapy.
3. Hops Hopfen / Hops
Hops (Humulus lupulus) contain 8-prenylnaringenin (8-PN), which has estrogen receptor activity. This type of active ingredient comes from extracts, and the content in regular beer cannot be compared, so drinking beer to "supplement estrogen" is not recommended.
4. Flaxseed Leinsamen / Flaxseed
Flaxseed contains lignans, which can be metabolized by gut microbiota into metabolites with weak estrogenic activity. Flaxseed also provides dietary fiber and fatty acids, making it very suitable as part of a daily diet.
4. Common German menopause herbs that are not typical phytoestrogens
Black cohosh Traubensilberkerze / Black Cohosh
Black cohosh (Actaea racemosa, also known as Cimicifuga racemosa) is representative in German herbal medicines for menopause. The European Medicines Agency (EMA) has a formal herbal medicinal product assessment for the use of specific formulations for menopausal hot flashes and sweating. It should not be simply classified as a typical phytoestrogen, nor is it equivalent to supplementing human estrogen. Black cohosh products have had reports related to liver damage; if warning signs such as fatigue, dark urine, jaundice, or upper abdominal pain occur, use should be discontinued and medical evaluation sought.
Sage Salbei / Sage
Sage is traditionally used in European herbal applications for regulating sweating, and menopause-related research is continuously accumulating. It is recommended to use it in gentle forms such as tea, and concentrated essential oils should not be taken in large amounts on one's own.
Chaste tree Mönchspfeffer / Chaste Tree
Chaste tree (Vitex agnus-castus) is more commonly associated with premenstrual syndrome (PMS), cyclical breast discomfort, and other related issues, and is not a typical phytoestrogen, nor should it be described as "natural estrogen."
St. John's wort Johanniskraut / St. John's Wort
It mainly involves mood-related uses and is not a phytoestrogen. It may have important interactions with many medications, including some hormonal contraceptives, anticoagulants, and other prescription drugs, so a doctor or pharmacist should evaluate it before use.
Complete guide: German phytoestrogens and auxiliary herbs for women's symptoms
This list is categorized by mechanism of action and usage scenarios, not a recommended list for "natural hormone replacement therapy." Some plants are common in Germany, while others are for cross-cultural or research purposes; having estrogen receptor activity does not mean they can increase human estrogen or treat menopause. The following is a summary, and individual products still need to be interpreted by extraction method, dosage, and clinical trials.
A｜Phytoestrogens and phytoestrogen-like compounds (Phytoestrogens)
| Plant / German name | Scientific name | Representative component | Common discussion topics | Scientific evidence and reminders |
|---|---|---|---|---|
| Soybeans Soja | Glycine max | Isoflavones: genistein, daidzein | Food nutrition; often studied in issues such as menopausal hot flashes | More human studies; belongs to the food and nutritional supplement route |
| Red clover Rotklee | Trifolium pratense | Isoflavones: biochanin A, formononetin | Common in menopausal supplements | Research is continuously accumulating; it is recommended to choose standardized extract formulations with clear labeling |
| Hops Hopfen | Humulus lupulus | 8-prenylnaringenin (8-PN) | Phytoestrogen component research | Mainly studied in extract formulations; drinking beer is not recommended as a substitute |
| Flaxseed Leinsamen | Linum usitatissimum | Lignans | Dietary fiber and plant-based fat source | Suitable for daily dietary intake |
| Sesame Sesam | Sesamum indicum | Sesamin lignans, etc. | General food and nutritional source | Suitable for daily dietary intake |
| Kudzu Kudzu | Pueraria lobata | Isoflavones such as puerarin and daidzin | Traditional use; phytoestrogen research | Human studies are continuously accumulating; extract and food dosages differ |
| Alfalfa Luzerne / Alfalfa | Medicago sativa | Coumestrol, etc. | Phytoestrogen research | Currently mainly at the basic research stage |
| Fennel Fenchel | Foeniculum vulgare | Fennel oil and other components; some estrogen-like activity is at the preclinical research stage | Mainly traditional gastrointestinal herbal uses | Mainly used in traditional diets and herbal teas |
B｜Herbs for Menopause and Women's Symptoms (Non-Typical Phytoestrogens)
| Plant / German name | Scientific name | Common discussion topics | Evidence and safety reminders |
|---|---|---|---|
| Black cohosh Traubensilberkerze | Actaea racemosa | Hot flashes, sweating | Specific formulations have EMA herbal medicinal product assessments. Liver damage warning signs |
| Sage Salbei | Salvia officinalis | Traditional use related to sweating and night sweats | Menopause-related research is continuously accumulating; gentle forms such as tea are recommended, essential oils should not be taken orally |
| Chaste tree Mönchspfeffer | Vitex agnus-castus | Premenstrual syndrome (PMS) and cyclical discomforts | More commonly used for premenstrual and cyclical issues; please consult first if using hormone-related treatments |
| St. John's wort Johanniskraut | Hypericum perforatum | Mood-related uses | Major drug interactions, including some contraceptives |
| Lemon balm Melisse | Melissa officinalis | Mild stress, sleep, and digestive discomfort | Traditionally used for relaxation and stress relief, a general herbal tea option |
| Valerian Baldrian | Valeriana officinalis | Sleep difficulties | Some formulations have sleep-related research; may cause drowsiness |
| Lavender Lavendel | Lavandula angustifolia | Stress, anxiety, or sleep difficulties | Please choose formulations labeled for oral use. Essential oils should not be taken orally arbitrarily |
| Passionflower Passionsblume | Passiflora incarnata | Mild nervousness, sleep | Traditionally used for relaxation and bedtime drinking |
| Motherwort Frauenmantel | Alchemilla vulgaris | Traditional women's cyclical herbs | Traditionally used as a women's herbal tea |
| Yarrow Schafgarbe | Achillea millefolium | Traditional gastrointestinal and menstrual related uses | Please pay attention to those with Asteraceae allergies |
| Wild yam Wild Yam | Dioscorea villosa | Common in natural progesterone-related marketing | Diosgenin is a plant ingredient and will not directly convert to progesterone in the human body; please read the labels carefully when purchasing |
| Fenugreek Bockshornklee | Trigonella foenum-graecum | Traditional nutrition and other uses | Traditionally used as a spice and nutritional ingredient; please consult first for those taking blood sugar medications and other medications |
Special reminder: This category is not all focused on menopause: Chaste tree is mainly used for PMS-related issues; Valerian, Lemon balm, Lavender, and Passionflower are more focused on sleep or stress support. If women have persistent hot flashes, vaginal dryness, recurrent urinary tract infections, abnormal bleeding, or mood symptoms, it is recommended to seek medical evaluation, and herbs can serve as an auxiliary for daily maintenance.
Reading method: First distinguish between food, nutritional supplements, and approved herbal medicines, then compare standardized extracts, human trials, and interactions. For those with a history of hormone-sensitive diseases such as breast cancer, liver disease, pregnancy and breastfeeding, or taking prescription drugs, please confirm with medical professionals before using concentrated extracts.
C｜Other women's health plants worth knowing (non-hormone replacements)
The following 10 plants are commonly found in women's health, stress, sleep, or urinary tract health discussions, each with different usage directions.
| Plant / German name | Scientific name | Research or traditional usage direction | Evidence and safety |
|---|---|---|---|
| Dong Quai Dong Quai / Chinesische Engelwurz | Angelica sinensis | Traditional women's cyclical herbs | Use according to product labels; please consult first for those taking anticoagulants |
| Evening primrose Nachtkerze / Evening Primrose | Oenothera biennis | Evening primrose oil contains GLA and is often used for premenstrual or breast discomfort | Use according to product labels; research is continuously accumulating |
| Borage Borretsch / Borage | Borago officinalis | Seed oil contains GLA and is commonly found in skin nutrition products | Please pay attention to whether the product removes pyrrolizidine alkaloids when purchasing; use according to product labels |
| Ginseng Ginseng | Panax ginseng | Fatigue, subjective quality of life-related research | Formulations differ greatly, please read the labels when choosing; please consult first for those taking medications |
| Ashwagandha Ashwagandha / Schlafbeere | Withania somnifera | Stress and sleep-related research, not a phytoestrogen | Please consult first for pregnancy, thyroid disease, or liver disease; use according to product labels |
| Saffron Safran | Crocus sativus | Mood and PMS-related small studies | Some studies use extracts at about 30 mg/day |
| Maca Maca | Lepidium meyenii | Small studies related to libido and subjective menopausal feelings | Some studies at about 2–3.5 g/day; individual reactions vary |
| Cranberry Cranberry / Moosbeere | Vaccinium macrocarpon | Research related to prevention of recurrent urinary tract infections in women | You can pay attention to the PAC content of the product when purchasing |
| Chamomile Kamille | Matricaria chamomilla | Traditional uses for mild sleep, tension, and digestive discomfort | Please pay attention to those with Asteraceae allergies |
| Nettle Brennnessel | Urtica dioica | Traditional herbal and nutritional uses | Traditionally used as herbal tea and nutritional ingredient |
D｜Nutrients and supplements commonly discussed in menopause research (non-phytoestrogens)
In addition to herbs, human studies related to menopause also often explore the following nutrients and supplements. They are not phytoestrogens, each corresponding to different maintenance directions such as bones, sleep, cardiovascular, or microbiota.
| Component / German name | Common discussion topics | Evidence and safety |
|---|---|---|
| Vitamin D Vitamin D | Related to calcium absorption and bone health, a nutrient commonly discussed in postmenopausal bone maintenance | Dosage varies by blood concentration, excessive amounts may cause hypercalcemia, it is recommended to have a doctor evaluate first |
| Omega-3 Fatty Acids Omega-3-Fettsäuren | Cardiovascular and blood lipid-related research, commonly found in daily maintenance | Fish oil may affect blood clotting, those taking anticoagulants need to consult a doctor or pharmacist first |
| Probiotics Probiotika | Intestinal and urogenital microbiota-related research | Effects vary by strain, please read the strain label when choosing; menopause-related research is continuously accumulating |
| Melatonin Melatonin | Sleep-related research | Regulations vary by region, in Taiwan it is mostly managed as a medicine; may cause drowsiness and interact with other medications, should be evaluated by a doctor or pharmacist first |
| Vitamin E Vitamin E | Some small studies explore hot flashes | High doses may increase bleeding risk, please consult first for those taking anticoagulants |
| Magnesium Magnesium | Discussions related to sleep, muscle relaxation, and mood | Those with poor kidney function need to be cautious, excessive amounts may cause diarrhea |
Reminder: Whether nutrients need to be supplemented, it is recommended to have a doctor, pharmacist, or nutritionist help evaluate the suitable type and amount based on dietary status and test results.
Quick reference for research dosages: Which ones have numbers?
Important: The table below is a "research / food dosage example" of some human trials or general diets, not a personal dosage prescription, official recommended intake, or universal dosage for all brands. Extract mg, isoflavone mg, and raw plant g are not interchangeable; research results of specific formulations cannot be directly extrapolated to other brands.
| Plant | Dosage form | Research or dietary amount and reminders |
|---|---|---|
| Soybeans / Soy isoflavones | General soy products are food; research often calculated in isoflavones mg/day | 2025 meta-analysis median about 75 mg isoflavones/day; only for research use |
| Red clover Rotklee | Standardized isoflavone extract | Some clinical trials about 40–80 mg isoflavones/day |
| Hops Hopfen | 8-PN or standardized extract | Formulation differences are large, please follow product labels; recommended to use standardized formulations as a standard |
| Flaxseed Leinsamen | General food | Common dietary portion about 1–2 tablespoons/day |
| Black cohosh Traubensilberkerze | Specific standardized rhizome extract formulation | Clinical and approved formulations commonly about 20–40 mg extract/day, varies by product specifications; cannot convert across extracts |
| Chaste tree Mönchspfeffer | Standardized fruit extract | Some PMS studies use about 20 mg/day specific extract |
| St. John's wort Johanniskraut | Standardized extract | Some mood studies about 300 mg, 3 times daily; only as a research example, many interactions, do not apply on your own |
| Valerian Baldrian | Root extract | Some sleep studies use about 300–600 mg before bed; product differences are large |
| Lavender Lavendel | Oral standardized lavender oil formulation | Some anxiety studies use 80 mg/day specific formulation; essential oils should not be taken orally arbitrarily |
| Saffron Safran | Standardized extract | Some mood or PMS studies about 30 mg/day |
| Maca Maca | Powder or extract | Small studies about 2–3.5 g/day; only for research use |
| Vitamin D, Omega-3, Probiotics, Melatonin, Vitamin E, Magnesium | Nutrients / Supplements | Based on diet, test results, product labels, and professional advice; results of specific strains or formulations cannot be applied to each other |
| Other herbs | Different plants, parts, extracts | Please follow approved medicine instructions or professional advice |
For concentrated formulations such as red clover, black cohosh, St. John's wort, and lavender oil, active ingredients, extraction ratio, medicine / supplement classification, and labeled usage should be checked first. When having liver disease, hormone-sensitive diseases, pregnancy and breastfeeding, or taking prescription drugs, please confirm with a doctor or pharmacist first.
5. How are German products categorized? Food, supplements, and herbal medicines are not the same
- Lebensmittel (Food): Soy milk, tofu, flaxseed, etc. daily diet.
- Nahrungsergänzungsmittel (Nutritional supplements): Such as isoflavone or red clover concentrated capsules; supplement and medicine regulations differ.
- Pflanzliche Arzneimittel (Herbal medicines): Must be evaluated according to applicable medicine laws and formulation data, regulations differ from general supplements.
- Menopausale Hormontherapie (Menopausal hormone therapy): Is another medical option, can discuss with a doctor whether it is suitable for yourself.
6. Who needs to pay special attention?
Those receiving treatment for breast cancer or other hormone-related diseases, pregnant or breastfeeding, having liver disease, or taking prescription drugs should consult medical professionals before using concentrated plant extract supplements. If severe hot flashes, sleep difficulties, abnormal vaginal bleeding, etc. symptoms occur, it is recommended to seek medical evaluation for the cause and treatment options.
7. Key summary
Phytoestrogens are not human estrogen; "containing phytoestrogens" does not mean it will cause hormone imbalance, everyone's reactions also differ. The most worth learning from German natural women's care is to clearly see ingredients, dosage, formulation, human studies, and safety, then choose the method suitable for yourself.
8. Munich Stars related product extended reading
The following are related products sold on our site, categorized by ingredient type for readers to compare, does not mean all products have the same clinical evidence, nor is it providing personal medication advice based on symptoms. Some products may be out of stock, please refer to the real-time information on the product page.
Doppelherz Red Clover Isoflavone Capsules
Red clover isoflavone supplement, belongs to the nutritional supplement route; related research is continuously accumulating.
Sanct Bernhard Rotklee-Vital-Tee Red Clover Herbal Tea
Red clover herbal tea, mild flavor, suitable for daily drinking; dosage is different from standardized capsules.
Remifemin Black Cohosh Herbal Medicine
Black cohosh formulation, does not belong to typical phytoestrogens; please use according to product instructions and pay attention to liver safety warning signs.
Salus Menopause Care Tea 15 Bags
Menopause theme herbal tea, suitable as a daily herbal drink option, also a small ritual to leave some time for yourself to relax.
Purchase reminder: Although the above products are marked as active in the backend, some inventory counts are negative, please confirm actual supply before purchasing. Those with hormone-related diseases, liver disease, or taking medications should consult medical professionals before using concentrated extract products.
References and official information
- Viscardi G, et al. Effect of Soy Isoflavones on Measures of Estrogenicity: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Advances in Nutrition. 2025;16:100327. Free full text.
- US NIH, National Center for Complementary and Integrative Health. Red Clover: Usefulness and Safety.
- European Medicines Agency. Cimicifugae rhizoma — Herbal medicinal product.
- Milligan SR, et al. Identification of a Potent Phytoestrogen in Hops (Humulus lupulus L.) and Beer. J Clin Endocrinol Metab. 1999;84:2249–2252. PubMed.
This article is general health education information, does not constitute personal diagnosis or treatment advice.