The Claim

A high-fiber, low-fat dietary intervention administered over one year reduces serum bioavailable estradiol concentration by 13 pmol/L in women with a history of breast cancer, independent of weight loss.

Source: Effects of a high-fiber, low-fat diet intervention on serum concentrations of reproductive steroid hormones in women with a history of breast cancer.

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
60score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

Cause and effect
1 study reviewed
In plain English

Women with a history of breast cancer who follow a high-fiber, low-fat diet for one year have a 13 pmol/L reduction in bioavailable estradiol in their blood, regardless of whether they lose weight.

See the scientific wording

A high-fiber, low-fat dietary intervention for one year significantly reduces serum bioavailable estradiol concentration by 13 pmol/L in women with a history of breast cancer, independent of weight loss, suggesting a potential biological pathway through which diet may influence post-diagnosis hormonal environments.

Why this might work

Eating more fiber causes estrogen to stick to waste in the gut, so less of it gets recycled back into the blood. This lowers the amount of active estrogen circulating in the body.

Supported mechanismbased on 1 study

What the research says

1 study
  1. Study: Effects of a high-fiber, low-fat diet intervention on serum concentrations of reproductive steroid hormones in women with a history of breast cancer.

    In women who had breast cancer, eating more fiber and less fat for a year lowered the active estrogen in their blood by about 13 points—even without losing weight. This suggests diet might help control hormones that affect breast cancer risk.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.