Genistein
A plant with hormone-like effects
- Type
- Isoflavone
- Typical amount
- Isoflavone studies use varying amounts; extracts are standardized for genistein content.
- Best taken
- As directed on the formula label
- Caffeine
- None
- Main source
- It is found in soybeans and soy foods, and in smaller amounts in other legumes.
- Evidence level
- Limited / emerging
Genistein is an isoflavone, a plant compound found mainly in soy that can interact mildly with oestrogen receptors.
What is Genistein?
Genistein is an isoflavone, a plant compound found mainly in soy that can interact mildly with oestrogen receptors.
How Genistein works in the body
It is studied for antioxidant effects and, in some research, for influencing fat-cell behaviour and metabolic markers. In practical terms, this is the mechanism weight-loss formulas are counting on when they include genistein.
What the research says about Genistein and weight
Human research on Genistein specifically for weight is limited or early-stage. Much of the rationale comes from traditional use, lab studies, or its general nutritional role. That doesn’t mean it doesn’t help — only that strong clinical proof for a weight effect isn’t established yet.
How much Genistein to take
Isoflavone studies use varying amounts; extracts are standardized for genistein content. Always check the label of your specific formula — blends often contain less genistein than studies use, especially inside proprietary blends that don’t disclose exact amounts.
Food sources and supplement forms
It is found in soybeans and soy foods, and in smaller amounts in other legumes.
Why Genistein appears in weight-loss formulas
It appears in women-focused metabolic formulas for its isoflavone and metabolic research.
Safety, side effects and interactions
Generally well tolerated; those with hormone-sensitive conditions should seek advice given its mild oestrogenic activity. As with any supplement, if you are pregnant, breastfeeding, taking medication or managing a health condition, check with your doctor first.
How to choose a quality Genistein supplement
When choosing a Genistein product or a formula containing it, look for one that discloses the actual amount of genistein (not just a proprietary-blend total), uses a recognizable form, and is made by a brand with third-party testing or GMP manufacturing. More isn’t always better — match the dose to what research and the label suggest, and be wary of products that hide quantities behind a blend.
A plant with hormone-like effects
Genistein can weakly mimic oestrogen, which is why soy isoflavones are studied especially in women’s metabolic health.
Common questions about Genistein
What does Genistein do for weight loss?
How much Genistein should I take?
Is Genistein safe?
How strong is the evidence for Genistein?
Will Genistein alone make me lose weight?
Does the dose in supplements match research?
Supplements with Genistein
Formulas in the SourceLean directory that list Genistein or a closely related form among their ingredients:
Related ingredients
Explore other compounds commonly found in weight-loss formulas:
Ingredient insights, explained
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