The Source of Soy Isoflavone’s Power
Can you produce Equol—or not?
Even if you can produce Equol…
Otsuka Pharmaceutical’s Equol
Among the components derived from soy, Equol is now attracting
attention as a key ingredient that supports the health and
beauty of women entering the Menopause - a time of hormonal
fluctuations.
Otsuka Pharmaceutical’s EQUELLE is a convenient way to
directly consume this promising compound, Equol.
However, research has revealed that not everyone can fully
benefit from soy isoflavones.
This discovery led to a focus on Equol—a metabolite produced
when daidzein, a type of soy isoflavone, is converted by
specific gut bacteria.
Equol has been shown to exert stronger effects than soy
isoflavones themselves, making it the true source of their
power.
Soy isoflavones are found in soybeans and soy-based foods such
as tofu, okara, abura-age (fried tofu), natto, and soy
milk.
Otsuka Pharmaceutical’s research indicates that to support the
health and beauty of women in the Menopause, a daily intake of
10 mg of Equol is ideal. On average, producing 10 mg of Equol
in the gut requires about 50 mg of soy isoflavones.
Despite its benefits, not everyone can synthesize Equol in the gut.
Equol production depends on the presence of Equol-producing
bacteria in the intestines.
If you lack these bacteria, no matter how much soy isoflavone
you consume, your body cannot convert it into Equol.
This explains why some people benefit from soy isoflavones
while others do not.
For those without Equol-producing bacteria, daidzein is
absorbed as-is, without conversion.
Even if you can produce Equol, you still need to consume
soy-based foods regularly to supply the raw material.
If you cannot produce Equol naturally, EQUELLE offers a way to directly supplement Equol itself.
In Japan, about 50% of the population can produce Equol. Similar rates are observed in China and Korea, where soy consumption is high. In contrast, the figure drops to around 30% in Europe and the United States.
(Source: Journal of Japan Society of Menopause and Women’s Health, 2012)
Reports suggest that only 20–30% of younger individuals can produce Equol. The reasons remain unclear, but dietary habits are believed to play a role. Westernized diets have reduced opportunities to consume soy-based foods compared to the past.
According to the
2015 National Health and Nutrition Survey,
younger generations consume fewer legumes than those aged 50
and above.
The Ministry of Health, Labour and Welfare recommends a daily
intake of 100 g of legumes, yet the average
intake among women in 2015 was only
58.6 g.
This highlights the importance of consciously incorporating
soy products into daily meals.
*1 From the Ministry of Health, Labor and Welfare's "Summary of the 2015 National Health and Nutrition Survey Results"
In fact, clinical trials conducted on individuals capable of
producing equol revealed noticeable day-to-day variations in
production.
During a 7-day study, 25 participants consumed identical
meals, and changes in urinary equol excretion were measured.
Results showed significant daily fluctuations in some
participants.
In one case, equol production was not detected at all after
the fourth day.
These findings suggest that even equol producers may
experience changes in production levels due to factors such as
shifts in gut environment.
A study involving 524 Japanese equol producers measured
urinary equol excretion under normal dietary conditions. The
results revealed that sufficient equol production was not
guaranteed.
Approximately 80% of participants produced
less than 10 mg of equol per day.
For women in the menopause maintaining health and beauty is
thought to require about 10 mg of equol daily.
This study indicates that even among equol producers, many
Japanese may not generate enough equol through their usual
diet.
Reference: Ueno, T. et al., J Functional Foods, 2014, 7, 129-135 (partially modified)
Most are excreted within a day after consumption.
So, eating a large amount of soy foods in one day, thinking
“I’ll make up for tomorrow,” will not deliver the desired
effect, as they are mostly eliminated by the next day.
To harness the benefits of equol, soy-based foods must be
consumed daily.
The same applies when taking EQUELLE.
The key to Otsuka Pharmaceutical’s equol lies in the lactic acid bacterium Lactococcus 20-92.
Currently, about 15 types of equol-producing bacteria have
been identified in the human colon. However, for food
applications, safety as a probiotic is essential.
Otsuka focused on safe strains such as bifidobacteria and
lactic acid bacteria, and after years of research, discovered
Lactococcus 20-92, leading to the creation of EQUELLE.
It is the only equol-containing food made by fermenting soy
with lactic acid bacteria.
With EQUELLE, you can easily and safely continue your
intake—helping you stay comfortable during life’s transitional
stages.
Probiotics are defined as “live microorganisms that, when
administered in adequate amounts, confer a health benefit on
the host by improving the balance of gut flora.”
However, this balance is easily influenced by lifestyle
factors such as stress, poor diet, and lack of sleep.
To ensure smooth equol production and maximize its benefits,
it’s important to maintain a regular lifestyle and eat a
well-balanced diet that supports gut health.
As we age, beneficial bacteria like bifidobacteria tend to
decrease, while harmful bacteria increase.
Alongside adopting gut-friendly habits, using EQUELLE can help
maintain equol levels and support daily health.
