Genistein is a plant-derived isoflavone found in soy. It acts as a phytoestrogen, meaning it can interact with estrogen receptors in the body.

What are the main benefits of genistein?

Genistein is most studied for reducing menopausal hot flashes and supporting bone health in postmenopausal women. It also has antioxidant and anti-inflammatory activity, while anticancer effects in humans are not confirmed.

What is a typical genistein dosage?

Common supplemental amounts are about 50–150 mg per day. The best dose can vary by product and goal, and some formulas combine genistein with calcium and vitamin D for bone support.

Is genistein safe for everyone?

Genistein is generally well tolerated for many adults, but it may not be appropriate for people with hormone-sensitive conditions or those who are pregnant or breastfeeding. Discuss use with a clinician if you have a history of estrogen-sensitive cancer or significant endocrine conditions.

Does genistein interact with medications?

Because genistein can affect hormone signaling, it may interact with hormone therapies such as estrogen-containing treatments or anti-estrogen medications. If you take prescription medications, ask a pharmacist or clinician before starting genistein.

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Vitamin B

Vitamin B1 (Thiamine)

Vitamin B2 (Riboflavin)

Vitamin B3 (Niacin)

Vitamin B5 (Pantothenic Acid)

Vitamin B6 (Pyridoxine)

Vitamin B7 (Biotin)

Vitamin B9 (Folic Acid)

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Vitamin B12 (Cobalamin)

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Trimethylglycine (Betaine)

NMN (Nicotinamide Mononucleotide)

Pyrroloquinoline Quinone (PQQ)

D-Chiro-Inositol

Coenzym Q10 (Ubiquinone)

Betaine HCL

Nicotinamide Riboside

Vitamin B8 (Myo-Inositol)

Choline

Citicoline (CDP-Choline)

Coenzyme Q10 (Ubiquinol)

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Calcium Alpha-Ketoglutarate

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Magnesium Bisglycinate

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Manganese (Bisglycinate)

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Cat's Claw (Uncaria tomentosa)

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Glucosamine Sulfate

Chondroitin Sulfate

Glucosamine Sulphate 2KCL

Genistein

Moderate study situation·7/10

A higher score indicates better study conditions, but not necessarily effectiveness.

Genistein is a soy isoflavone (phytoestrogen) supplement, most studied for menopause symptom relief, bone health, and potential anticancer properties.

Menopause Support Anti-inflammatory Cancer-inhibitor Antioxidant Bone Health Hormone Balance

dose range

50–150 mg

1–2 daily doses

Consumption

Take with food to improve absorption.

Not fat-soluble.

Best time

Morning or with first meal recommended.

Description

Genistein is a plant-derived isoflavone commonly found in soy products. It acts as a phytoestrogen and is used primarily for its potential benefits in menopausal symptom management, bone health, and hormone-related health conditions.

benefits

Main effects with level of evidence

Moderate

Note on evidence

Genistein is supported by moderate quality evidence mainly from randomized trials in menopausal symptom relief and bone health, with emerging observational and preclinical evidence for anticancer effects.

Menopausal symptom relief

Moderate

Genistein supplementation may reduce frequency and severity of hot flashes and improve other menopausal vasomotor symptoms.

Particularly relevant for: Postmenopausal women

2 · PubMed 3 · NIH ODS Fact Sheet: Soy

Bone health support

Moderate

Daily genistein may help maintain or improve bone mineral density in postmenopausal women, potentially lowering risk of osteoporosis when combined with calcium and vitamin D.

Particularly relevant for: Postmenopausal women

3 · NIH ODS Fact Sheet: Soy

Potential anticancer properties

Limited

Genistein may modulate estrogen signaling and inhibit cell proliferation in certain cancers, based on observational studies and preclinical models; clinical benefits in cancer prevention or treatment are not confirmed.

Particularly relevant for: General adult

4 · PubMed

Antioxidant and anti-inflammatory effects

Limited

Genistein exhibits antioxidant activity and reduces some markers of inflammation in preclinical and limited human studies.

Particularly relevant for: General adult

1 · WebMD 5 · Examine.com

Safety & Information

Important safety information & known risks

For educational purposes only • not medical advice

Generally safe for most, but contraindicated in people with hormone-sensitive cancers or untreated thyroid disease.

warning notices

May cause mild gastrointestinal upset or allergic reaction in sensitive individuals.
Contraindicated in patients with estrogen-sensitive cancers or active thyroid dysfunction.
Long-term safety beyond three years is insufficiently studied.
Avoid use if you have or have had hormone-sensitive cancers, such as estrogen-receptor positive breast cancer.
Avoid if you have untreated thyroid disorders or take thyroid medications, as genistein may interfere with thyroid hormone activity.
Use only under medical supervision if taking hormone replacement therapy or anti-estrogen medications.
Monitor use beyond three years with a healthcare provider due to limited long-term safety data.

Known interactions with medications

Thyroid hormone (levothyroxine)
Hormone replacement therapy
Antiestrogen drugs

Contraindications / special precautions

Estrogen-receptor positive cancer
Thyroid disorders (untreated or unstable)

interactions

Important interactions between active ingredient ↔ supplement / medication / food

Genistein may interact with thyroid hormones and hormone therapies due to its estrogenic and goitrogenic activity.

Potential to interfere with thyroid hormone absorption/effect.

nutrient · Thyroid hormone

CautionModerateSeparate by 2h

Why

Genistein can inhibit thyroid peroxidase and may interfere with thyroid hormone synthesis or absorption, especially when iodine intake is low or with levothyroxine therapy.

recommendation

Monitor thyroid function and separate use by several hours if on thyroid medication.

1 · WebMD 3 · NIH ODS Fact Sheet: Soy

May interact with hormone therapies.

drug · Hormone therapy (estrogen, antiestrogens)

CautionModerateAvoid concurrent use unless under medical supervision.

Why

Genistein's estrogenic actions may alter effects of hormone replacement or antiestrogen drugs (like tamoxifen); could diminish efficacy or increase adverse effects in hormone-sensitive conditions.

recommendation

Consult a healthcare provider before combining.

1 · WebMD 5 · Examine.com

mechanisms of action

Brief explanations of how it works