Fermented soy products linked to lower risk of death

In continuation of my update on the benefits of soy

Natto with Miso and Mayonnaise

A higher intake of fermented soy products, such as miso and natto, is associated with a lower risk of death, finds a study from Japan published by The BMJ today.

However, the researchers stress that the findings should be interpreted with caution as they may have been affected by unmeasured (confounding) factors.

In Asian countries, especially Japan, several types of soy products are widely consumed, such as natto (soybeans fermented with Bacillus subtilis), miso (soybeans fermented with Aspergillus oryzae), and tofu (soybean curd).

It is, however, still unclear whether different soy products, especially fermented soy products, are associated with specific health effects.

So a team of researchers in Japan set out to investigate the association between several types of soy products and death from any cause ("all cause mortality") and from cancer, total cardiovascular disease (heart disease and cerebrovascular disease), respiratory disease, and injury.

They base their findings on 42,750 men and 50,165 women aged 45-74 years who were taking part in a study based in 11 of Japan's public health centre areas.

Participants filled in detailed questionnaires about their dietary habits, lifestyle, and health status. Deaths were identified from residential registries and death certificates over a follow-up period of nearly 15 years.

The researchers found that a higher intake of fermented soy (natto and miso) was associated with a significantly lower (10%) risk of all cause mortality, but total soy product intake was not associated with all cause mortality.

Men and women who ate natto also had a lower risk of cardiovascular mortality than those who did not eat natto, but there was no association between soy intake and cancer related mortality.

These results persisted even after further adjusting for intake of vegetables, which was higher among those consuming larger portions of natto.

The authors point out that fermented soy products are richer in fibre, potassium and bioactive components than their non-fermented counterparts, which may help to explain their associations.

However, this is an observational study, so can't establish cause, and the researchers cannot rule out the possibility that some of the observed risk may be due to other unmeasured factors.

They conclude: "In this large prospective study conducted in Japan with a high rate of soy consumption, no significant association was found between intake of total soy products and all cause mortality. In contrast, a higher intake of fermented soy products (natto and miso) was associated with a lower risk of mortality."

Increasing evidence has suggested that fermented soy products are associated with health benefits, write researchers in a linked editorial. Whether people eat those products depends on their food culture, they say, but some countries already include soy and fermented soy products in their dietary guidelines.

Further studies are still required, however, "to refine our understanding of the health effects of fermented soy, and perhaps to inform the development of healthier and more palatable products," they conclude. "These efforts should be collaborative, including not only researchers but also policy makers and the food industry."

https://phys.org/news/2018-09-video-natto-stinky-slimy-soybean.html

Soy shows promise as natural anti-microbial agent

In continuation of my update on soy

Soy isoflavones and peptides may inhibit the growth of microbial pathogens that cause food-borne illnesses, according to a new study from University of Guelph researchers.

Soybean derivatives are already a mainstay in food products, such as cooking oils, cheeses, ice cream, margarine, food spreads, canned foods and baked goods.

The use of soy isoflavones and peptides to reduce microbial contamination could benefit the food industry, which currently uses synthetic additives to protect foods, says engineering professor Suresh Neethirajan, director of the BioNano Laboratory.

U of G researchers used microfluidics and high-throughput screening to run millions of tests in a short period.

They found that soy can be a more effective antimicrobial agent than the current roster of synthetic chemicals.

The study is set to be published in the journal Biochemistry and Biophysics Reports this summer and is available online now.

"Heavy use of chemical antimicrobial agents has caused some strains of bacteria to become very resistant to them, rendering them ineffective for the most part," said Neethirajan.

"Soy peptides and isoflavones are biodegradable, environmentally friendly and non-toxic. The demand for new ways to combat microbes is huge, and our study suggests soy-based isoflavones and peptides could be part of the solution."

Neethirajan and his team found soy peptides and isoflavones limited growth of some bacteria, including Listeria and Pseudomonas pathogens.

"The really exciting thing about this study is that it shows promise in overcoming the issue of current antibiotics killing bacteria indiscriminately, whether they are pathogenic or beneficial. You need beneficial bacteria in your intestines to be able to properly process food," he said.

Peptides are part of proteins, and can act as hormones, hormone producers or neurotransmitters. Isoflavones act as hormones and control much of the biological activity on the cellular level.

Soy Supplements Can Cool Hot Flashes

In continuation of my update on Soy...

Taking soy to relieve hot flashes has received mixed reviews over the years. Now, researchers who took another look at 19 published studies find that soy supplements may help, at least over time. Soy has been touted as an alternative treatment to hormone replacement therapy after HRT was linked to an increased risk of breast cancer.

“For many women with symptoms and especially with concerns about hormone replacement therapy, trying soy for six to 12 weeks to see if it relieves their symptoms could be a first line of treatment,” says Melissa Melby, PhD, a professor of medical anthropology at the University of Delaware.

Researchers conclude that, Soy isoflavone supplements, derived by extraction or chemical synthesis, are significantly more effective than placebo in reducing the frequency and severity of hot flashes. Additional studies are needed to further address the complex array of factors that may affect efficacy, such as dose, isoflavone form, baseline hot flash frequency, and treatment duration.


Ref : http://journals.lww.com/menopausejournal/Abstract/publishahead/Extracted_or_synthesized_soybean_isoflavones.98844.aspx

Soy protein alleviates symptoms of fatty liver disease, study suggests

In continuation of my update on Soy

Soy protein alleviates symptoms of fatty liver disease, study suggests