Phytoestrogens

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Phytoestrogens – Mother Nature’s Gift 

The phytoestrogen story may well prove to be the most significant breakthrough in human health since the discovery of vitamins and minerals.  To date there have been in the region of 7,000 published medical papers exploring the powers of phytoestrogens, many of which reported exceedingly encouraging findings.  Despite this, phytoestrogens are little known outside medical and nutritional research circles.  The vast majority of doctors completely underestimate the impact that dietary factors can have on our health.  It would be difficult for you not to be impressed by the wealth of the published medical studies carried out by conventional researchers around the world, and by the real life case histories explaining the beneficial effects of phytoestrogens and how they have improved their health. 

On the downside, too much oestrogen can increase the risk of hormone-dependant cancers, in particular breast cancer and womb cancer.  Women who take hormone replacement therapy (HRT) for prolonged periods are at an increased risk of these diseases. 

Phytoestrogen are Mother Nature’s gift allowing us to top up on naturally occurring oestrogens on a daily basis.  The reason researchers are so interested in phytoestrogen is that they appear to boost the ‘good’ effects of oestrogen whilst minimising the ‘bad’ ones. 

What are phytoestrogens? 

Phytoestrogens are a family of naturally occurring substances with a chemical structure very similar to our own female hormone oestrogen.  Oestrogen (which is also present in small amounts in men) has many positive effects, including:

• An important role in the reproductive organs of males females
• Regulation of menstrual cycles and pregnancies
• Reduction in the risk of heart disease and the bone-thinning disease osteoporosis
• Keeping skin, hair and nails in good shape

Phytoestrogens: The Great Hormone Regulators 

How can phytoestrogens both increase and reduce the influence on oestrogen?  The effect is in almost certainly due to their ability to bind to oestrogen receptors in tissues such as the breast.

When oestrogen is in oversupply, phytoestrogens play ‘musical chairs’ with the hormone in competition for these receptors.  Some of the phytoestrogens will inevitably displace oestrogen, and because they are many times weaker in their effect, they reduce the cancer promoting effects of the hormone.  Phytoestrogens also dilute the effects of the environmental oestrogens (xenoestrogens), which can be even more harmful to the body than normal oestrogen.  On the other hand, if you are producing too little oestrogen (for example, at menopause), phytoestrogens can give levels a natural boost, helping combat symptoms such as hot flushes and osteoporosis. 
 

The power of phytoestrogens 

A wealth of research in recent years as demonstrated that a phytoestrogen rich diet, as consumed in Asia, Southern France and the Mediterranean can perform what may easily be termed ‘medical miracles’.  It has been shown to:

• Dramatically reduce menopausal hot flushes and other oestrogen withdrawal symptoms like dry vagina
• Unblock clogged arteries
• Maintain cholesterol levels within the normal range
• Significantly reduce cholesterol levels
• Help to generate new bone, thus protecting our bones against osteoporosis
• Normalise blood glucose levels, thus helping to control diabetes
• Regulate the menstrual cycle
• Help prevent oestrogen dependant cancers and even have the ability to reverse cancer cells back to normal healthy cells!

The main types of Phytoestrogens 

Lignans are found mainly in wheat bean and linseeds (flaxseed).  They are converted by bacteria in the gut into a number of hormone like compounds which are believed to lower the risk of certain cancers, particularly breast cancer.  When linseeds are consumed, intestinal bacteria action results in the production of up to 800 times more of these lignans than from any other food. 

Isoflavones are found mainly in legumes and pulses and are the most well known for their effects on oestrogen metabolism and female health.  Different foods contain differing amounts and types of isoflavones, but overall, the richest sources are Soya beans (including tofu, and Soya milk), chickpeas, lentils and mung beans.  Red clover largely taken as a supplement rather than eaten as a food, contain all four major isoflavones.  

There are four main types of isoflavones:

Genistein is the most extensively studied isoflavone to date.  It was identified as a plant oestrogen in 1966, but it took over 20 years for it’s anti-cancer properties to be recognised by medical scientists.  Japanese researchers were the first to discover the genistein, found in soy and many pulses, can block the signal that triggers the growth of a cancer cell.  It acts as an anti-oestrogen in a similar way to the drug Tamoxifen administered for breast cancer and it would appear without the side effects.

Daidzein was the second major isoflavone to be discovered.  Like genistein it is found predominately in pulses and acts as an anti-cancer agent.  In laboratory studies, it is able to cause cancer cells to revert to their normal healthy state.  Daidzein is also particularly involved in bone health, and may slow oestrogen levels.  

Biochanin and Formononetin are the more recently discovered isoflavones.  Unlike the earlier two, they aren’t found in Soya, but they do occur in good amounts in red clover, chickpeas, lentils and mung beans.  Although they are closely chemically related to genistien and diadzein, biochanin and formononetin have their own unique effects.  As well as acting as cancer protective compounds they are known to help lower blood fats.  

How do phytoestrogens work? 

It seems that they mimic oestrogen’s role in the body and are able to compete against oestrogen within the harmful environmental oestrogens (xenoestrogens) for the receptor sites at the entrance to the cells.  So, for example, genistein, the look-alike oestrogen, is able successfully to take up occupation in the breast tissue, thus preventing the more potent natural oestrogen, produced by the body, from ‘converting’ normal cells into cancer cells.  Because genistein is able to block the uptake of oestrogen it acts as an ‘anti-oestrogen’, in a similar way to the drug Tamoxifen administered to the breast cancer victims, and it would appear, without the side effects.   

Sources of phytoestrogen 

Phytoestrogens are found in many common plant foods:

Soya products, particularly soya milk, tofu and soya flour. The Soya bean, which is known in China as ‘ta-tou’ meaning the ‘greater bean’ is referred to in America as ‘the miracle bean’, and has been shown to be at least an equivalent to source of protein to animal products. They are also a good source of fibre and important nutrients including B vitamins, the minerals calcium, iron and zinc.  Soya is one of the few plants that contain omega 3 essential fatty acids, which predominate in marine fish oils, and are thought to be useful in the prevention of heart disease and cancer.

Linseeds  (sometimes known as flaxseeds) are rich source of omega-3 fatty acids, which are predominantly derived from oily fish.  These fats are essential for a healthy nervous system, soft skin, bright eyes, strong immune system, the health benefits are immense.  Fresh organic golden linseeds, Linusit Gold which are much nicer than the brown seeds that are available, can be combined with breakfast cereal each day.  Two tablespoons of seeds, either whole or preferably ground, should be sprinkled over the cereal or used in muesli as an ingredient.  Linusit Gold can be ground either in a coffee grinder or a blender, or simply with a pestle and mortar, and then stored in a sealed container in the refrigerator.  They can also be sprinkled over salads, bakes, combined with yoghurt and milk and even included when baking fresh bread.  It is important to consume plenty of liquid with linseeds, so if you are not combining them with milk, juice or yoghurt have a drink afterwards. 

Other sources: 

• Lentils,

• Chickpeas, 

• Mung beans, 

• Sunflower, 

• Pumpkin and 

• Sesame seeds,

• Red clover

• Other beans, greens and yellow vegetables to some extent and the plant red clover

Phytoestrogens are similar in structure to the female hormone oestrogen, but they are only a fraction as potent.  Despite this research shows that in high concentration, typical of the Asian diet, they protect us against hormonally related cancers, having the ability to block the uptake of excess oestrogen by the body, but the supplement low oestrogen levels in the body.    

Managing the menopause with phytoestrogens 

For at least three-quarters of the women in the Western world, the menopause brings with rapid changes and unwanted symptoms, often disrupting life and causing utter misery.  Frequent hot flushes during the day, and sweats at night, resulting in exhaustion, disorientation and despondency.

The menopause is a transition, which signals the end of a woman’s monthly fertility cycle, and in order to have a smooth passage through it, our bodies need to be in really good shape. 
 

Phytoestrogens and the Menopause   

In 1990 a study published in the British Medical Journal, conducted by a group of Australian workers, showed that women going through the menopause, regularly consuming foods and drinks that contained naturally occurring oestrogens, including soya, linseeds and red clover, were able to bring about the same positive changes in the lining of the vagina, as women taking HRT. 

In 1992 a validation of how effective phytoestrogens are at the time of the menopause was published in The Lancet.  The study concluded that Japanese women do not seem to experience hot flushes and other menopausal symptoms because the Japanese diet contains foods rich in plant oestrogens.  

The most recent audit of Women’s Nutritional Advisory Service (WNAS) patients showed that within 4 months of the following programme:

• 85% had recovered from oestrogen withdrawal symptoms of hot flushes, nights sweats, dry vagina and insomnia
• 90% had overcome their ‘physical’ symptoms like fatigue, weight gain and headaches, and ‘mental’ symptoms like anxiety, confusion and irritability

Did you know? 

• Until recently, there were no words in the Japanese language for the term ‘hot flush’, largely because women in Japan hardly experienced any adverse symptoms at the time of the menopause.
• When compared with Western men, whilst a similar number of Japanese men became victims of prostate cancer, far fewer of them actually died as a result.  Instead they die of other illnesses or old age, with prostate cancer rather than from the cancer itself.
• The number of victims of breast cancer and other hormonally related cancer amongst Asian, who consume an Asian diet, is dramatically lower than Western casualties.  For example, ten times more women currently die of breast cancer in England and Wales than in Korea
• Whilst almost half of all Americans die of cardiovascular disease, in Shanghai only one in 15 becomes a victim of cardiovascular disease. 
• Although 50% of some Western populations become victims of diabetes, in other countries diabetes is hardly a health issue.

Key symptoms 

From a survey conducted by WNAS, of 500 women who had recently gone through their menopause, it was discovered that there were three main groups of symptoms that occur at the menopause.   

Cancer Preventions and phytoestrogen. 

Cancer is one of the commonest diseases of our time, and probably the most feared illness.  Rightly so, for according to a World Health Organisation study on populations of some fifty countries, the incidence of hormone-associated cancer is so much higher in industrialised western societies when compared to the Asian populations.  For example, depending in which Western country you reside in, your chances of dying form breast of prostate cancer are between ten to twenty times greater than those consuming a typically Asian diet, whilst living in countries like Japan, China or Thailand.  More than one in four people will have cancer during their lifetime.  After heart disease, cancer is the most common cause of death in Western countries, and is on the increase because of the ever-expanding population. 

One study published in the Lancet in 1997, measured the levels of phytoestrogen in the urine – an indicator of the amount in the diet -  in women with newly diagnosed early breast cancer, and healthy control subjects.  The results found that the women with breast cancer had generally lower levels of phytoestrogen than healthy women. The are many ways to lower the chances of illness and it is possible with a Master in Public Health to help those around you live a healthier life. 

Phytoestrogens – Guardians of our health  

Fruit and vegetable consumption has also been linked to the reduction of breast cancer.
A study of 2,400 Greek women noted that women with the highest intake of vegetables, four to five servings daily, had a 46% lower risk of breast cancer compared with women who had the lowest intake, fewer than two servings per day.  

Phytoestrogens reduce Heart Disease 

Coronary heart disease is now the most common cause of death in women in Western societies, with heart attacks claiming more than three times more lives than breast cancer, and stokes, more than twice as many.  It actually accounts for 21% of deaths for women over the age of 45 in the UK.  Women are protected from heart disease by oestrogen, prior to the menopause.  Once they are no longer protected by oestrogen, the incidence of heart disease escalates post-menopause.

When we enter the world, our arteries are clear and flexible, designed to contract and expand in order to accommodate blood flow.  As time progresses, if we mistreat our body, the arteries begin to narrow due to the development of “plaque”.  This is made up of fatty deposits of cholesterol and fibrous tissue, the internal diameter of the blood vessels reduces.  The process of arterial narrowing and hardening is called atherosclerosis.  When plaque deposits have caused the arteries to narrow, the heart has to work harder to pump the blood around the body.  When arteries supplying the heart itself become completely blocked, the muscle in portion of the heart that is denied both of oxygen and nutrients will die, and the result is a heart attack.  Whilst those living in the Western world are falling like flies, the majority of Asian communities generally reach old age with healthy blood vessels. 

The power of phyoestrogens 

It was discovered that Soya protein lowers cholesterol levels almost by accident.  Studies showed that Soya protein lowered cholesterol levels by an average of 14% within 2 weeks, and by 21% at the end of the 3 weeks.  More and more research has been undertaken to look at the effects of Soya on cholesterol levels.  An analysis of forty published studies was undertaken by Dr Kenneth Carrol at the University of Western Ontario.  His conclusion was that thirty-four of the studies he did produced a drop in LDL cholesterol levels in particularly, by 15% or more.  Other more recent studies have shown that as well as reducing the level of LDL, Soya has been successful in raising the levels of HDL.  Researchers at Sydney University have reported that isoflavone supplementation is a promising alternative to HRT for reducing cardiovascular risk in postmenopausal women.  Their study involving 21 menopausal women, showed that 5 weeks of treatment with 40mg isoflavone tablet (containing a mixture of four major isoflavones derived from red clover) achieved a highly significant reduction in hardening the arteries, to levels typically found in a 30 year old woman.  Even genetically raised cholesterol levels have been seen to drop by 26% in a four week Italian study, published in 1991.  The Italians are so convinced about the value of Soya in lowering cholesterol that it is now provided free of charge by the Italian National Health Service to those with high cholesterol levels.
 
The Cholesterol Factor 

Cholesterol is needed by our bodies for the manufacture of vitamin D and sex hormones, as well as a number of other important functions.  It is produced by the liver and also found in animal foods, but the most usual cause of excess levels in the bloodstream is a diet high in saturated fats. 

Because of its fatty nature, cholesterol doesn’t mix well with blood, so it binds with protein in a combination known as a lipoprotein.  There are two lipoproteins; high density lipoprotein (HDL) and low-density lipoprotein (LDL).  

HDL and LDL – The Good and The Bad!

Soya reduces the LDL cholesterol, and actually raises the levels of HDL. 
High levels of LDL (bad cholesterol) are well known to be associated with heart disease as LDL transports cholesterol to the arteries where it can collect and cause damage. 
By comparison, HDL (good cholesterol) is beneficial because it transports cholesterol away from arteries, taking it to the liver for removal from the body. 

Pyhtoestrogens and the prevention of Osteoporosis 

Osteoporosis means ‘porous bones’, and is literally a condition that results in the thinning of the bones.  It has become an epidemic in the Western world, with an estimated 5 million sufferers in the UK alone.  Every three minutes someone in the UK sustains a fracture due to osteoporosis.  Hip fractures claim more lives than cancer of the ovaries, cervix and uterus put together. 

Japanese women have half the hip fracture rate of the women in the West, and the women in countries like Hong Kong and Singapore suffer even fewer fractures.  One explanation could be that Asian women are more active.  Japanese women, who traditionally sit on the floor, will probably have stronger muscles and bones as a result of their regular movement, compared to a woman leading a sedentary lifestyle.  But there is more to it than that, as new research is beginning to unveil. 

Here are some interesting facts:

• The incidence of hip fracture is the lowest in countries with a low calcium intake
• Phytoestrogens have a positive influence on the bone strength – countries with a low incidence of hip fractures also have a high dietary isoflavone intake!
• In this country alone, over £950 million is spent each year on hip fractures
• It is estimated that women die each year following an oesteoporotic hip fracture

Not all Oestrogen in good for us! 

Unlike phytoestrogens, environmental oestrogens known as xenoestrogens, ‘xeno’, being Greek for foreign, are far from beneficial to our health.  Horror story reports about xenoestrogens have been widespread in the media in the last few years, telling tales of reduced sperm counts in the men and infertility, and even increased rates of oestrogen-related cancers.  Some 37 chemicals have been identified as being able to mimic oestrogen in the body and although they are weaker than natural oestrogen, they are thought to interfere with the systems that regulate the production of oestrogen and sex hormone function. 

• A study of Florida alligators inhibiting DDE-polluted rivers revealed low rates of hatching, and those eggs that did hatch were predominantly female offspring, or males with abnormally small penises.
• Male Texan turtles whose shell, prior to hatching had been exposed to oestrogen-mimicking chemicals, developed ovaries.

The relationship between Breast Cancer and Xenoestrogens 

Many scientists now believe that repeated exposure to xenoestrogens is related to the increase of breast tumours in women, and this is borne out by many studies including an Israeli study.  In Israel, breast cancer fell sharply between 1976 and 1986.  The dramatic fall in death from breast cancer was due to a ban in 1978 on the use of 3 organochlorine pesticides.  Until 1978 milk had been contaminated with pesticides at rates of between 100 and 1,000 times greater than levels found in the USA!!

Sources of Xenoestrogens

• Chlorinated hydrocarbons
• DDT
• PCB’s
• Dioxins and fungicides
• By-products of manufacturing processes
• Contraceptive pill

How Xenoestrogens differ from Phytoestrogens 

The chemical structure of environmental oestrogens is strikingly different from both oestrogen found in the body and oestrogen found in plants. 

• Phytoestrogens are transported through the bloodstream where they hunt out compatible receptor site and bring about positive hormonal changes.

• Xenoestrogens interact with the receptor sites within a cell, but they block normal hormone activity. 

What is Genetically modified Soya?  

When Soya is modified to make it resistant to all-purpose weedkiller herbicide, there is a risk that the plant could contain higher levels of residues, which, in turn, could worsen allergies in some and cause skin problems in others.  Whilst the Mansanto Roundup Soya bean has been declared safe to eat by American and European regulatory bodies, concerned nutritionists argue that food gene technology is still so new that the long-term risks are not quantifiable.  The WNAS advise patients to avoid genetically modified Soya products and with this in mind, conducted a survey of British manufacturers (a letter was sent to the major food companies, requesting their assurance that they do not use or support the use of GMOs) for the “Phyto Factor” to determine which foods are free from modification.  However, since conducting the survey, legislation has changed, and continues to change.  Consumer pressure has prompted food manufacturers to review their existing policies on genetic engineering for the better, and the WNAS will endeavour to update their survey when appropriate.