The results of a large, 3-year study published recently, demonstrate that in contrast to studies showing that some conventional hormone replacement therapies increase mammographic breast densityⁱ, standardised supplement of red clover isoflavones (Promensil) has a neutral effect on breast density in women with a family history of breast cancer. Mammographic breast density has consistently been associated with risk for breast cancer.ⁱ

The study received funding support from the breast cancer charity Breakthrough Breast Cancer.

Tens of thousands of women around the world use Promensil (red clover isoflavone phytoestrogens) daily. They are recommended by menopause experts as a natural alternative to HRT to help control hot flushes and night sweats associated with the menopause, used alongside lifestyle changes^.ii

Professor Trevor Powles, consultant oncologist and lead investigator for the study carried out at the Royal Marsden Hospital and the University Hospital of South Manchester, said “Reassuringly for women, this study shows that these phytoestrogens do not cause any oestrogenic increase in breast density in women who have a family history of breast cancer. This would indicate that they are unlikely to cause an increased risk of breast cancer. This 3-year study confirms similar findings from previous, shorter-term studies.”

Promensil (a standardised supplement of red clover isoflavones) has been shown to reduce frequency of hot flushes by 60%, in a randomised placebo controlled study in menopausal women.ⁱⁱⁱ

In addition, two systematic reviews and meta-analyses of all 17 randomised controlled trials (RCTs) of supplementation with red clover or soy isoflavones demonstrate a significant reduction in menopausal hot flush frequency with red clover isoflavone use, particularly in women with frequent flushes^.iv,v

Mr Nick Panay, Consultant Gynaecologist, Queen Charlotte’s Hospital, London said, “These 3-year data are exciting findings that add to a broader evidence base showing that standardised, quality controlled supplements of red clover isoflavones have a good safety profile.  I recommend isoflavones derived from red clover as an effective option to women who can’t take or don’t want to take HRT - while stressing the importance of choosing a well-researched product that provides a minimum daily intake of 40mg of isoflavones.”

Isoflavones are phytoestrogens which literally means ‘plant estrogens’.  They occur naturally in the diet in foods such as peas, lentils, soya and other beans, chick peas and red clover. Isoflavones are similar in chemical structure to the body’s own estrogen. When consumed in adequate amounts around the time of the menopause, they are able to mimic some of the effects of the body’s own estrogen to help with maintaining health and well-being, particularly hormonal balance when levels of hormones are declining.

The red clover isoflavone breast cancer safety study wasled by Prof. Trevor Powles, Parkside Oncology Clinic, London and Prof. Anthony Howell, University Hospital of South Manchester and published in the journal Menopause International. The study involved 401 healthy women with at least one first degree relative with breast cancer who received a standardised supplement of 40mg red clover isoflavones or placebo for 3 years in a randomised, double-blind, placebo-controlled trial.

Results showed that Promensil did not adversely affect breast density, skeletal strength or cardiovascular status. In post-menopausal women endometrial status was not adversely affected. The adverse event profile was similar between Promensil and placebo groups.