Supplement
Soy isoflavones are plant compounds from soybeans that act as phytoestrogens, binding estrogen receptors, especially the beta type, to give a mild estrogen-like effect. People mostly look at them for menopause symptoms, where the evidence is strong, and a pooled analysis of randomized trials found bone mineral density improved. The bone evidence is moderate, and findings that blood calcium and IGF-1 went up were small and limited.
Sources: PMID 31290343
- Updated
- How we grade
- 2 studies cited
- Best evidence
- Grade B
- Conditions studied
- 2
- Outcomes
- 5
- Graded outcomes
- 0120
Evidence by condition
- Strong
- Moderate
- Limited
- Very limited
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Bone Mineral Density Moderate Improvement | Improves (the measure goes up) | Moderate effect | 1 study | 5,313 people | ||
Studies that measured bone mineral density | ||||||
| Bone turnover markers | Changes; see studies | 5,313 people | ||||
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Serum Calcium Small Increase | Improves (the measure goes up) | Small effect | 1 study | 26,247 people | ||
| IGF-1 Small Increase | Improves (the measure goes up) | Small effect | 26,247 people | |||
| Serum Phosphorus | Changes; see studies | 26,247 people | ||||
Key findings
- Bone Mineral DensityImproves (the measure goes up)
- Serum CalciumImproves (the measure goes up)
- IGF-1Improves (the measure goes up)
Shop the evidence-backed picks
Third-party tested Soy Isoflavones products, in the forms the graded studies used where we can match them.
- Grade B
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Studies cited
2 studies from PubMed
- Effects of isoflavone interventions on bone turnover markers and factors regulating bone metabolism in postmenopausal women: a systematic review and meta-analysis of randomized controlled trials.
- Soy isoflavones prevent bone resorption and loss, a systematic review and meta-analysis of randomized controlled trials