Search results for soy isoflavones

More on soy

Posted by Liz on Feb 6, 2009 in colon cancer | 2 comments

I’ve posted several times about the potential effectiveness of soy isoflavones for safely relieving certain symptoms such as hot flashes. You can find those posts here.

Evidence now suggests that the benefits of soy may extend beyond troublesome menopause symptoms.  In fact, it appears that eating soy foods may reduce the risk of colorectal cancer after menopause.

In this study, published in February’s American Journal of Clinical Nutrition, researchers examined 68,412 women (ages 40 to 70) who were cancer- and diabetes-free at the start of the trial. Information on soy food intake was assessed at the start and then at follow up through in-person interviews and questionnaires.

Over the entire study, 321 colorectal cancer cases were identified. However, after adjusting any factors that might skew the results, the researchers found that:

• Total soy food intake was associated with a lower risk for developing colorectal cancer
• For each 5 gram increase daily in soy foods (~1 oz tofu), there was an 8% reduction in cancer risk
• The association between intake of soy foods and lowered colorectal cancer risk was mostly seen in post-menopausal women

Similar results were also observed for soy protein intake and isoflavones.

These promising findings suggest the potential to not only glean benefit from eating soy-rich foods during menopause but also well beyond menopause. Encouraging news!

Soy! Oh Boy!

Posted by Liz on Aug 27, 2008 in hot flash, nightsweats, women's health | 10 comments

It’s Wednesday, meaning that it’s time for me to debunk a popular myth about menopause or provide you with a bit of inspiration for hump day.

Tongues have been wagging a lot about soy isoflavones (plant-based compounds with estrogen-like properties)  with the most disturbing reports linking high doses to genetic damage and stimulation of estrogen receptors to promote breast cancer.

So, do you need to be worried if your current menopause diet includes lots of soy? (You can read more about the potential benefits of soy here.) Evidently, the answer is NO!

According to a newly published study in the Menopause Journal, unconjugated forms of soy isoflavones are safe and well tolerated at daily doses as high as 900 mg/day. (Unconjugated forms are more readily absorbed into the bloodstream.)

In this study, researchers administered soy isoflavones or placebo to 30 postmenopausal women for 84 days.  The goals of the study were to measure DNA damage, cell death and any changes that would indicate that estrogen was stimulated (which might lead to tumor growth). The researchers found no indication that high (900 mg) daily doses of soy caused DNA damage, increased cell death or affected estrogen. What’s more, any side effects (ocurring in only 1 woman) were mild or moderate in severity.

Granted, the study population is quite small and more data are needed to confirm these findings. Neverthless, the researchers do conclude that despite the considerable debate over the negative, estrogen-related effects of soy isoflavones, findings suggest only minimal effects.

If you are currently using soy isoflavones as a strategy to combat vasomotors symptoms like hot flashes and night sweats, eat with ease. It appears that you are not increasing your breast cancer risk. Nevertheless, as my grandmother used to say “everything in moderation.”

Happy News for Wednesday!

[Cross-posted at EmpowHer.com]

Loco for cocoa – chocolate and your heart

Posted by Liz on Jan 9, 2012 in heart disease | 2 comments

Last June and August, I wrote about the link between eating chocolate and improving heart health. Briefly, researchers have long been interested in flavonoids and in particular (at least in so far as menopause goes) in isoflavones. (See soy posts for more on isoflavones). The specific compound or molecule of interest in cocoa (the non-fat component cocoa bean extract or liquor) are flavanols, which are also found in lower concentration in apricots, peaches, apples, green and black tea, red wine and cider). Note that the quantity of flavanols in chocolate depends on manufacturing, including fermentation and roasting, and how much treatment is given to reducing bitterness and improving consistency. What this means is that dark chocolate has the highest concentration of flavanols and milk, the lowest.

What have researchers learned so far?

• Flavanols found in cocoa and cocoa powder may be powerful antioxidants and as such, help to mitigate certain factors that contribute to atherosclerosis, such as the formation of plaques in the arteries that lead to stroke and other coronary events. Thus, as antioxidants, they may actually neutralize toxic oxygen species circulating in the bloodstream.
• Experimental data suggest that ingestion of flavanols may help to regulate proteins and other compounds that encourage an inflammatory response to leads to heart disease.
• Flavanols may also help to stabilize the lining and muscular tone of the arteries and prevent them from narrowing.
• Additionally, flavanols may moderately protect against high blood pressures, although studies have been mixed.
• Finally, flavanols may help to maintain blood sugar levels and improve the ratio of good to bad fats in the blood.

However, while numerous studies suggest that chocolate may benefit the heart, less clear is whether or not a causal relationship exists. Still, the idea is attractive enough that researchers continue to delve into the potential benefits of functional foods containing flavonoids and in flavonols found in dark chocolate. This time, writing in the journal Appetite, they report on a newly published study that examined the effect of eating flavonoid-rich dark chocolate on a process called oxidative stress, in which the ratio of circulating oxygen free radicals  to circulating antioxidants is imbalanced (free radicals are those nasty, unstable molecules or atoms that can wreak havoc and lead to disease, including heart disease, diabetes and high cholesterol).

Over a period of three weeks, 25 healthy men and women were asked to eat 50 g of dark chocolate daily. The women in this particular study were premenopausal, primarily because use of hormone replacement has been shown to modify oxidative stress that has been attributed specifically to LDL (low density lipoprotein, also known as the bad cholesterol). They also omitted any other cocoa products from their diet and tea, red wine and other drinks that were rich in antioxidants.

Not only did eating dark chocolate daily have no impact on body mass index or the subjects’ weight, but it significantly increased the percentage of HDL (high density lipoprotein or good cholesterol) and led to a significant declines in blood fats levels as well. Dark chocolate consumption also appeared to lower markers of oxidative stress and damage to good fats in cells by almost 27% in women in the study, indicating a favorable effect on LDL, a change that was not similarly observed in men. This suggests that eating dark chocolate could possibly benefit women more than men, at least in terms of the heart. And, while menopausal women were not studied, the researchers say that the protective role of dark chocolate could possibly be especially favorable during menopause, when waning levels of estrogen make women particularly sensitive to oxidative damage and heart disease.

As with similar studies, we still don’t have a definitive cause and effect. However, a little dark chocolate has the potential to go a very long way.

Crow’s feet? What crow’s feet?!

Posted by Liz on Nov 14, 2011 in aging, appearance, menopause | 2 comments

Crow’s feet. Most of us start to develop them in our mid to-late 30s and by the time we reach the age of 50, they’re pretty pronounced. This is no surprise because aging skin is associated with a decline in elasticity and moisture. And, let’s face it, if you grew up with light-coloured eyes like I did, you have an even greater tendency to squint in bright light, another factor contributing to those tell tale lines around the eyes.  In women in particular, crow’s feet are a rule and not an exception, as aging is accompanied by a loss of estrogen, which has been linked with as great as a 30% loss of collagen in the dermis (the thick, sturdy layer of connective tissue that comprises about 90% of the skin’s thickness) within the first five years of menopause. Collagen, which is the most abundant protein in the body, is responsible for  skin’s durability and strength. As it declines, skin starts to sag and wrinkles form. Oh, happy day!

Unfortunately, researchers continue to debunk claims that replacing estrogen can improve the skin’s appearance. That’s the bad news. Likewise, don’t look for expensive moisturizers or facials to do the trick either. However, there are data that suggest that intake of soy isoflavones may improve aging skin. And once again, S-equol is the winner in the isoflavone antiaging department.

A bit of background…

If you are new to Flashfree, you may be unfamiliar with S-equol. Briefly, S-equol is a metabolite of a major soy isoflavone called daidzein. It has a particular affinity for estrogen receptors and possesses some estrogen-type activity of its own. S-equol is produced in the gastrointestinal tract however the ability to actually manufacture it depends on the presence of certain microflora there. Consequently, only 30% to 60% of individuals are actually able to produce S-equol on their own (although this figure is believed to be higher among Asians and vegetarians). (You can read a full range of posts on S-equol here)

Because skin cells responsible for producing collagen express estrogen, researchers believe that S-equol and its affinity for estrogen receptors may impact skin very similar to the way that estrogen does. In fact, when 101 Japanese menopausal women randomly took 10 mg or 30 mg standardized S-equol  (SE5-OH) or a sugar pill daily for 12 weeks, that is exactly what they found. Even more interesting was the fact that S-equol was studied in women who do not produce it naturally in their bodies (even though s-equol producers are believed to gain greater benefit from soy products).

Over weeks, researchers measured numerous skin parameters, including crow’s feet, wrinkles, the degree that the skin was hydrated, skin elasticity and loss of water through the skin. To equalize the playing field, measurements were taken in a room that was the same temperature and humidity level each time, and women were instructed to remove any cosmetics using the same cleansing foam 20 minutes before each exam. They were also advised not to alter anything about their diet or sun exposure during the study period.

The findings?

Both 10 mg and 30 mg daily standardized S-equol significantly improved crow’s feet wrinkles/reduced the total wrinkle area compared to placebo tablet. And,  30 mg daily dose also significantly decreased wrinkle depth as well. What’s more, ingesting S-equol supplements did not appear to affect uterine or breast tissues or hormone status, indicating that unlike hormone replacement, using S-equol to combat declining estrogen levels is safe.

So, how does it work?

Although researchers say that the need a longer observation period to confirm S-equol action on skin, they believe that like hormone therapy, it gradually boosts the quantity and quality of skin collagen, and may even help preserve skin hydration from within. Additionally, because skin aging does not solely rely on estrogen levels, S-equol may also act as an antioxidant and help transport nutrients to the upper and middle skin layers.  And more importantly, other studies have shown that when Japanese,White, Hispanic and African-American women were compared, the Asian women had the least amount of wrinkling and sagging. If you translate the findings and consider the degree of differences in wrinkling among ethnic groups, it is very possible that S-equol may benefit women living in the U.S. even more than their Japanese peers.

Is it possible that S-equol is truly a Fountain of Youth is in pill form? Yikes! This is pretty darn exciting! Me? I’m off to the store in search of standardized S-equol. Crow’s feet? What crow’s feet?!

Wednesday Bubble: Black cohosh – is it safe?

Posted by Liz on Jun 22, 2011 in herbal medicine | 2 comments

Back in 2009, I wrote a post regarding black cohosh (better known in scientific circles as Cimicifuga racemosa) and potential safety issues, namely harm to the liver. In it, I discussed a small case review that showed no link between ingestion of black cohosh and liver toxicity. And yet, in 2006 the European Medicines Agency and the Committee on Herbal Medicinal Products released a public statement alerting health authorities to 42 suspected liver reactions among women taking black cohosh. In the very same report, they noted how inadequately adverse reactions were documented. Indeed, only 16 of the cases were considered to have sufficient data to allow for proper assessment of a potential link, and of these, only four showed any sort of association, albeit, unproven. Regardless,  the statement resulted in Italian health authorities requesting a precautionary withdrawal of black cohosh preparations from the market, and UK authorities issuing strict label requirements and warnings.

Hence, I was intrigued when I ran across a detailed review of black cohosh safety, both from perspective of over 107 patient cases and of published study findings. Following is the lowdown:

• An Italian clinic regularly prescribed 500 mg or 1000 mg daily black cohosh, either alone or in combination with other herbs (e.g. soy isoflavones, red clover or alfalfa) for treatment of menopause symptoms and disorders (e.g. anxiety, depression, hot flashes and joint pain). None of these herbs were prescribed to women with previous cancer of the breast, ovaries, uterus or pituitary gland. Moreover, the researchers say that they had not received any reports of any sort of adverse event.
• Still, following the European health statement, they contacted 107 women in good health and in different phases of menopause, took blood samples, underwent clinical examination and participated in phone interviews to evaluate if they were still taking the herbs. Of these women, only five had chronic but benign liver disease and one, hepatitis.

The findings? Despite the four patients suffering from prior benign liver disease, there was no additional sign of liver problems nor altered laboratories indicating a worsening condition or a new condition. Nor were there any clinical signs of liver damage after a year of using high dosages of black cohosh.

The researchers who reviewed and examined patients as well as the published literature point out that the liver is central to metabolizing most drugs and hence, there is a potential for an adverse liver event from taking nearly every medication that involves liver metabolism. They note that a step-by-step examination is also necessary to rule out other causes of liver damage, including infection, alcohol use and related conditions. In so far as herbs go, they write that “it is very important before an official statement about any adverse reaction referred to an herb based product to know the brand, dose of substance assumed, type of extract [and] content of possible contaminants.” They go on to state that it is their opinion the statement could actually be used as proof that black cohosh liver toxicity is scarce because despite over a million doses used worldwide annually, there is not any fully proven case of liver toxicity. Moreover, they claim that black cohosh safety has already been established in over 3,800 participants in clinical trials.  Their conclusion? black cohosh should be considered safe, at least in so far as liver toxicity goes.

What should you do?

If you wish to try black cohosh, speak to a licensed practitioner well versed in herbal medicines. Look for a standardized form to insure that the pills contain what they say they do. And if you start feeling poorly while taking black cohosh? Stop immediately and contact the person responsible for your care.

Black cohosh and liver toxicity. This one appears to be a bubble bursting worthy.