The results, published in The Lancet (online edition) today, are likely to further boost sales of soy isoflavone products, with many European consumers already aware of the connection between the ingredient and its benefits on menopause symptoms.
Israeli soy products manufacturer Solbar said it saw big peaks in sales following each of three recent trials concluding the high risks associated with HRT. In the last year the company, which claims to be the leading soy isoflavone supplier in Europe, has seen impressive growth of around 30 per cent in isoflavone sales in Europe.
Dutch firm Acatris also reported similar benefits to its soy product sales in 2003.
After the findings of the Women's Health study in 2002, linking HRT use to a significant rise in ovarian cancer, a major UK trial (on more than 1 million women) last year reported that risk of breast cancer was four times greater with use of combination (progestagen-oestrogen) HRT compared to oestrogen-only therapy. It was also the first to report an increase in risk of death from breast cancer for HRT users compared with women who have never used HRT.
Sales of natural phytoestrogen products, such as soy isoflavones, red clover and black cohosh, surged following the dramatic findings.
But the news was followed by advice from the UK's medicines watchdog late last year that HRT should no longer be recommended for prevention of osteoporosis, meaning that natural products that can protect bone health will also be in greater demand.
"Research indicates that there is definitely some substance to suggest that isoflavones can be effective for bone health. But clinical trials on osteoporosis are long-term and many of the studies have not yet published their findings," Gary Brenner, marketing director of Solbar, told NutraIngredients.com.
However he said the next generation of women's products will likely include ingredients that support bone health, such as added calcium.
The new Swedish study was launched because the increasing survival of women with breast cancer has made the management of menopause an important clinical issue. The HABITS trial was one of several trials established in the 1990s to assess the possible risk of recurrent breast cancer for women using HRT. Originally planned to include at least 1300 women followed up for five years, the trial was stopped on December 17, 2003, after an average follow-up of just over two years.
The steering committee for the trial were concerned that early results from the study showed an unacceptably high risk of recurrent breast cancer for those women randomized to receive HRT; of 345 women (all of whom had had previous breast cancer and were randomised to HRT or no HRT) with at least one follow-up assessment, 26 in the study arm allocated HRT reported a recurrence (or a new case) of breast cancer, compared with seven women who received therapy other than HRT for menopausal symptoms.
In an accompanying commentary in The Lancet, Rowan T Chlebowski from the Harbor-UCLA Research and Education Institute and Nananda Col from the Brigham and Women's Health Hospital in Boston, USA conclude: "…considering all available evidence about the effect of hormone therapy on breast cancer and chronic disease, the HABITS investigators' conclusion that even short-term use of hormone therapy poses an unacceptably high risk of breast cancer can now reasonably guide clinical practice for women with breast cancer…Alternative safe and effective strategies for the difficult problem of menopausal symptoms in these women now need to be developed".
These 'alternatives' could however come in the form of functional foods, rather than supplements.
"We are hearing requests for a better taste profile and questions about the levels of isoflavones that can be formulated into food. There is going to be further development of bars, beverages and soy-fortified breads to specifically target women's health," predicted Brenner.
The new study findings will appear in the February 7 print edition of The Lancet.