Soy Isoflavones

Soy Isoflavones: an alternative against menopausal symptoms

Since it was discovered by the first ancestors of the Chinese civilization, Soy has been one of the most significant sources of protein for human consumption. Its cultivation began in the fertile lands of East Asia, from where once its great nutritional value was known, it started its journey west, ending up expanding into vast regions of Asia and the Old Continent. It would not be until the late nineteenth century when its fame arrived in America, two of whose countries, Brazil and Argentina, have now emerged among the main producers of this legume in the world.

Its international market acquired enormous importance during the period between both world conflagrations, which was due to the paralysis of the regular supply of coconut oil and palm kernel by the Far East. This caused the vegetable fat industry to focus on soybean as an oleaginous plant that could replace those.

One of the treasures that this plant conceals the presence in its chemical composition of Isoflavones. Soy Isoflavones form a block of substances endowed with a structure similar to those of the main group of sex hormones of the human species, estrogens, a detail that decisively conditions their use and application in food and pharmacology. The most abundant compounds, which represent the hard core of its biological action, are three: Genistein, Daidzein and Glycitein.

Table of contents

Where do Soy Isoflavones come from?

Chemically, Isoflavones fall within the large group of polyphenols, composed of more than six thousand substances whose natural location is closely linked to the plant kingdom, being widely dispersed in botanical species of very varied types and origins.

The interest of this chemical complex for applications and benefits in human health resides in that there is a great number attributed to Soy Isoflavones, to a greater or lesser extent, phytoestrogenic capacity, a condition that allows them to be recognized within the organism as equivalent molecules to female estrogens.

This leads to metabolic actions and chemical reactions that can be decisive in the functioning of some parts of the body, as will be analyzed later.

Its parallelism with Estrogens

Ingredient Soy Isoflavones
Estrogens are steroid sex hormones (receiving this name because they derive primarily from cholesterol), mainly synthesized in the ovaries but also in the adrenal glands (two capsules located next to each kidney of enormous endocrine importance), for which men also have them.

The basic function of estrogen is to fine-tune the development of secondary sexual characteristics of women, such as breast growth, widening of the hips, higher voice tone or lesser development of hair follicles.

In essence, it is estrogen that gives women their recognizable morphology.

In addition, a direct link has been detected between cases of female infertility and a poor rate of estrogen synthesis, the lack of which, apparently, can promote the formation of tumors, especially of the breast.

 Its properties and benefits

Generally speaking, Isoflavones behave as antioxidants at cell membrane level and contribute to the reducing the intensity of menopausal and postmenopausal symptoms.

But in its natural state, within the tissues of the plant, the Isoflavones lack biological activity. Once ingested through food or nutritional supplements, the bacteria that make up the microflora of the small intestine make use of their enzymes to break down their molecules and transform them, so that is when a structure that is recognizable by the estrogen receptors appears and thus begin the deployment of their pharmacological activity.

However, the rapid expiration of the biological effects of these substances must be taken into account, since after a maximum of seven or eight hours they leave the bloodstream to be excreted by the body. This brevity of its survival requires a continued contribution in order to achieve a sustained benefit of its properties; For that reason, it is recommended to take two or three doses a day.

Benefits and properties of Soy Isoflavones

Thanks to their ability to act selectively on different estrogen receptors (alpha and beta), Soy Isoflavones are involved mainly in organs and tissues where beta-type receptors predominate, such as the the central nervous system (brain and spinal cord), bones and the walls of the arteries.

Isoflavones stand out, like all phenolic compounds, for their powerful antioxidant effect, which some research has come to compare with that of Vitamin E. Among them, Genistein and Daidzein are the most prominent. This property, on the one hand, adds to the previous one, since they avoid the oxidation of LDL and foam cells (modifications of muscle cells of the arterial wall and macrophages that arise when the formation of atheromatous plaques begins). On the other hand, this antioxidant power projects its benefits on the genesis of cancer, so they could have an influence on its prevention.

Due to its enzymatic inhibition capacity, it is possible to grant isoflavones, although it could be residual, an anti-cancer action, basically promoted by blocking three enzymes:

  • Tyrosine kinase: its inhibition is a precursor of an analogous effect on the expression of some oncogenes and the disappearance of some specific receptors of cell proliferation factors, such as tumor growth.
  • Topoisomerase II: Isoflavones kill cancer cells after chemically integrating into the DNA-topoisomerase II complex.
  • Aromatase: inhibiting it, they prevent the synthesis of 17-beta-estradiol (an estrogen) from testosterone, behaving as a suppressant for the formation of hormone-dependent tumors, such as breast cancer.

Isoflavones and Menopause

When reaching menopause, there are two primary phenomena that occur in the woman's organism: the production of ovules in the ovaries is suspended and the synthesis of estrogens significantly reduces. These changes imply, in most cases and to a greater or lesser degree, the appearance of a series of organic and psychic manifestations: fluid retention, intense sweating, hot flushes, dry mucous membranes, frequent headaches, irritability, emotional instability and difficulty sleeping, among others.

Due to these hormonal changes, it is necessary to address certain dietary guidelines, since during the climacteric period the woman sees an increased risk of osteoporosis, alterations in the sanguineous profile of lipids and cholesterol and arteriosclerosis, to which a tendency to gain weight is added.

To mitigate these uncomfortable manifestations and in turn elude therapies based on the administration of synthetic hormones, it is becoming more and more common for women to try natural treatments. It is about opting for a well-studied diet and reinforced with supplements that help alleviate menopausal symptoms.

And in that context, Soy Isoflavones have reserved a very remarkable role. Their impersonation of estrogen gives them, for example, the power to stop one of the most dreaded effects of menopause, bone decalcification, the prelude to osteoporosis. They do this by avoiding the mobilization of Calcium from the bone matrix (as an essential constituent of hydroxyapatite), while preventing the blockage of the absorption of this mineral, which is another consequence of the decrease in levels of circulating estrogens.

It is clear that the improvement of calcium absorption is one of the most outstanding properties of Soy Isoflavones.

Nobody doubts that maintaining an adequate bone density is key in the prevention of osteoporosis. And, regarding this, there are reliable studies that support these effects in the lumbar vertebrae, which can be expected to be extended to other bone elements if we take into account that they are short-term studies and that the replacement of the bone matrix occurs at a higher rate in the lumbar region of the spine than, for example, in the hip bones.

But, in general, they help to combat the external signs of menopause due to this compensatory function of the reduction of estrogen inherent to this stage. Consequently, it is during the climacteric period when isoflavones are most indicated, as well as the increase in calcium and Vitamin D intake.

Soy Isoflavones and menopause

Another benefit that deserves more attention is that they prevent cardiovascular diseases: this property is of great importance, since one of the dangers that lurk with the arrival of menopause is the higher incidence of disorders of this nature.

In this line, isoflavones are known to keep LDL levels (known as "bad cholesterol") and total cholesterol in blood in check, in addition to contributing to normalize the triglyceride profile, which translates into a decrease in the risk of arteriosclerosis.

The beneficial effect of isoflavones in the osteo-skeletal system is based on an anabolic action (ie, the "creative" aspect of metabolism) on the bone, stimulating the proliferation of osteoblastic cells (responsible for the formation of the bone matrix) while they protect these against oxidative damage caused by free radicals.

Its action is completed with an increase in the synthesis of DNA and Collagen and hindering the function of the osteoclasts (cells responsible for the resorption of the bone matrix, contrary in their function to osteoblasts).

Soy Isoflavones stimulate the synthesis of Hyaluronic Acid, an essential polysaccharide in the epidermis texture whose abundance improves the appearance of the skin because it slows down the wear of collagen and elastin, the two structural proteins of the skin tissue. In short, the greater formation of elastic fibres slows down the proliferation of wrinkles and fine lines on the skin.

The isoflavones cause a reinforcement of the immune system, which is a consequence of intensifying the activity of white blood cells and macrophages

The latters exert as purgers of the organism of everything they recognize as external substances, while the others, also called leukocytes, under different mechanisms according to the type, neutralize the invading microorganisms, keeping in their cellular memory the antigenic composition of these to double their efforts in possible future aggressions.

There are different lines of research open in relation to the possibility of preventing Alzheimer's disease in postmenopausal women, on which the scientists handle important indications that they can palliate the brain changes associated with this degenerative disorder.

During menopause, women experience an increased tendency to accumulate fat, and do so in two locations: in the liver, where hepatic steatosis occurs (thickening of this viscera), and in the adipose tissue, where the brown fat destined to the maintenance of the temperature is found and that is the cause of weight increase.

Regarding this last aspect, reaching the climacteric is commonly associated with a need to keep weight under control so as not to gain weight. Soy Lecithin, one of the products derived from this legume with a high concentration of isoflavones, can be an important support to stop this tendency to gain weight. It can be consumed in tablets or capsules.

Men can also benefit from Isoflavones

We must not forget that, as far as male sex is concerned, isoflavones can also give a helping hand. How do they do that? On the one hand, reducing the risk of suffering from prostate cancer and suppressing predisposing factors of cardiovascular accidents.

These effects must fit into the stage known as andropause, at which point the synthesis of sex hormones leads to certain physiological changes that especially affect the heart and circulatory system.

Contraindications and possible side effects of Soy Isoflavones


Logically, not everything is excellent in the relationship between Soy Isoflavones and the human organism. Given the different situations in which this can be found, we can speak of many others in which its intake may be compromised:

  • Allergies: Like any other food or chemical substance that comes into contact with the body, isoflavones are able to trigger allergic reactions in individuals that are hypersensitive to any of its components. Despite its scarce casuistry, it is the contraindication for which more incidence is described.
  • Hypothyroidism: its consumption among those suffering from this endocrine disorder and being medicated against it is discouraged, since they could lead to a depressant action of the activity of the thyroid gland and, consequently, neutralize the effects of the medication. In general, it can be said that isoflavones tend to cause an important loss of Iodine, so it is always recommended to accompany them with a supplement containing this mineral, which, in turn, is characterized by its scarce presence in the diet of most countries.
  • Undergoing an anti-tumor treatment: Soy Isoflavones can interfere with the action of the drugs indicated to fight breast cancer. In particular, they could nullify the action of Tamoxifen.
  • Undergoing a hormone treatment of any kind.
  • In adolescents, it can be a cause of disorders in the ovarian cycle, something that can be accentuated if alcohol is consumed simultaneously, a circumstance that is not negligible in these ages and that can even result in moderate or severe intoxication.

Side effects

In addition to the mentioned contraindications, the consumption of Soy Isoflavones is not exempt from the risk of side effects, mostly in the form of gastrointestinal disorders, such as flatulence or diarrhoea.

It is not ruled out that it can cause certain interference in the absorption processes of some minerals, especially Zinc and Iron.

Despite all of its qualities, it must be taken into account that in those people who, maintaining good levels of estrogen, regularly ingest correct amounts of isoflavones and in those who, taking them justifiably, consume them in excessive amounts, can be the cause of thyroiditis and, as a consequence, goiter. This type of risk is minimized if the isoflavones come from fermented foods such as those mentioned above.

As explained regarding their anti-tumor action, isoflavones inhibit the receptor tyrosine kinase, which having been demonstrated in adipose tissue cells of experimental rats, could counteract the effects of insulin in tissues that require the intervention of this hormone. Although there is currently no reliable evidence that isoflavones have been a causal factor of hyperglycaemia in people affected by diabetes mellitus, a chronic effect of possible resistance to the action of insulin is not ruled out.

For all the reasons given, the adoption of a controlled supplementation with Soy Isoflavones should be supervised by a specialist who assesses the real need for treatment and the advisable dose.

How to take Isoflavones

When considering their consumption through diet, the difference between soybean and the rest of the legume plants is substantial, while one hundred grams of soy contribute more or less 300 mg of isoflavones, with other legumes, three kilos would be needed to reach that figure.

Regarding the nutritional performance of its isoflavones, we can also reflect the important contrast between whole soybeans or sprouts and soybean oil and fermented soybean meal varieties, because in the latter case their absorption is much more efficient and effects are more noticeable. Among these varieties, the tempeh (fermentation of soy from Indonesia) or the tamari (authentic soy sauce) are its maximum exponents.

Phytoestrogens, which are abundant in an elite group of plant foods, are divided into different categories, such as Lignans (present in flax seeds and whole grain bread), Soy Isoflavones (also constituents of green tea and red tea) , coumestans of the legumes and the indoles in which the cabbages and other cruciferous vegetables are rich. If we had to make a list of foods rich in phytoestrogens, we could not leave out celery, garlic, cereals (rice, oats, wheat ...), legumes (beans, peas ...), some fruits (apple, cherries) ...), other vegetables (carrots, broccoli ...) and also seeds (pumpkin, sesame ...).

How to take Soy

Isoflavones can also be consumed through other foods that contain them after being added in the technological process of elaboration, as is the case of milk, juices or enriched yoghurts.

In any case, the scientific societies of gynecology and menopause recommend a daily intake of isoflavones in an interval between 40 and 80 mg. Assuming that phytoestrogens show their first organic signs after 8-10 weeks of starting their consumption, the importance of considering a sustained intake must be considered, ruling out shock treatments with short-term results. As for how to take them, it is preferable to eat them during meals, although the possible interference in their absorption of a fibre-rich diet should not be overlooked.

It can not be overlooked that having recently been assigned an important list of healthy properties, Soy Isoflavones, both the food industry and the nutraceutical have launched new production lines to fully exploit the potential of these compounds. In fact, in the market it is common to find different types of dietary supplements with striking mentions in the labelling about its enrichment in isoflavones.

Evidently, isoflavones must be consumed in high doses in order to make the most of their therapeutic benefits, which can only be achieved by ingesting synthetic products with a high concentration of isoflavones.

Soy, or any other plant of which we have cited as abundant in phytoestrogens, is a food that can be part of the usual diet, but its consumption, in no way guarantees sufficient doses of isoflavones to alleviate the shortage of estrogens in menopause.

Regardless of those ingested through the diet, in many cases it may be necessary to stock up on isoflavones included in nutraceutical supplements, that is, presentations based on tablets or capsules with a high concentration of active principle, but always under medical supervision.

Synergies of Soy Isoflavones with other substances

Because of its richness in phytoestrogens, it has been proven that Evening Primrose oil is an adjuvant of the production of substances similar to sex hormones, which gives it the ability to control the symptoms of menopause. In particular, the Evening Primrose seeds are an excellent source of one of the essential fatty acids of the Omega 6 series, gamma-linoleic acid (in short, GLA). This substance proves to be essential because its synthesis by the organism is impossible and, consequently, given its participation in various metabolic reactions, it must be included through food or nutritional supplements.

A regular intake of 250 milligrams of Evening Primrose oil ensures enough GLA to prevent cardiovascular disease and multiple sclerosis. And doing so in combination with soy isoflavones gives rise to a double benefit: balancing hormone levels naturally and mitigating uncomfortable climacteric hot flushes.

In another order of things, a herbal medicine that combines red clover and soy isoflavones has proven to be an effective remedy against menopausal symptoms. Numerous studies support the agonist and antagonist properties, as well as beneficial effects on health and the improvement of the quality of life and in particular in postmenopausal women. It is a combination that, in the menopausal area, dramatically decreases the intensity and frequency of hot flashes, as well as excessive sweating, while on the other hand being a regulator of the blood lipid profile.

Buy Soy Isoflavones

In the market there is a wide range of possibilities when purchasing Soy Isoflavone supplements.

In HSNstore, we can find HSN Essentials Soy Isoflavones with a concentration of 150mg per vegetable capsule, with a 40% isoflavone content, therefore has an important amount of this active principle.

4 Products
  • (3)
    Germinated soy extract with a 40% of Isoflavones. 150mg of Soy Isoflavones per capsule.
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    8.94 €
    14.89 €
      5.95 €
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  • Improve your health during this period in the life of a woman. Save money with our packs.

    Availability: In stock

    27.90 €
    In stock. Immediate delivery.
  • Hormonal support. 60mg of soya Isoflavones per serving.
    V VG
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    26.27 €
    30.90 €
      4.63 €
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  • Super concentrated isoflavones. It provides 76mg of soy isoflavones per daily dose.
    GF LF V VG
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    40.49 €
    44.99 €
      4.50 €
    In stock. Immediate delivery.