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Guarding Against Prostate Enlargement and Cancer In Men Over Forty
James Meschino DC, MS, ROHP
Aging and the Male Prostate Gland
The male prostate gland lies below the bladder and surrounds the urethra, which is the part of our plumbing system that acts like a flexible pipe to enable urine to flow from the bladder to the exterior of the body. Enlargement of this walnut-shaped gland can apply pressure to the urethra and obstruct the flow of urine as it exits the bladder, reducing the force of the urine stream during urination, and producing other symptoms such as frequent urination, night time awakening to empty the bladder, urgency of urination, and difficulty in initiating urination. Enlargement of the prostate gland is an extremely common problem in men over the age of forty, largely due to age-related hormonal changes that occur in the male body. It is noteworthy that many of the same age-related changes to the prostate gland that cause enlargement, are also associated with the development and spread of prostate cancer. So, any nutrition and supplementation strategies that help prevent prostate enlargement may also be important to the prevention of prostate cancer.
Nearly 60% of men between the ages of 40 and 59 years develop an enlarged prostate gland, also known as benign prostatic hyperplasia (BPH). By age 80, ninety percent of men experience significant symptoms of an enlarged prostate gland. There are some invasive medical techniques and certain drugs that are used to treat this condition, but the truth is that attention to proper diet and the use of specific supplements can block many of the steps that cause prostate enlargement and prostate cancer. Many of these supplements are routinely prescribed by medical doctors in certain European countries as the gold standard method to treat prostate enlargement problems.
After the age of 40 the male body experiences a decline in the production of the main male hormone testosterone, but a rise in other hormones such as estrogen, prolactin, luteinizing hormone and follicle stimulating hormone. These changes result in an increase in the amount of testosterone that is present within the male prostate gland, and increased conversion of testosterone to dihydrotestosterone (DHT) within prostate cells. The build up of testosterone in the prostate gland is largely attributable to decreased removal of testosterone, and the build up of DHT is due to increased activity of the enzyme (5-alpha-reductase), which converts testosterone to DHT.
The Link Between DHT and Prostate Enlargement and Cancer
As stated above, as men age (by age 40), the prostate gland tends to accelerate the rate at which it converts testosterone to dihydrotestosterone (DHT). The build-up of DHT in prostate cells stimulates prostate cells to divide and multiply at a faster rate than is considered to be normal and safe. This results in a greater number of prostate cells (with resulting greater prostate mass), which is associated with prostate enlargement and other problems. More rapid cell division rates also increase the chances of forming cancerous DNA mutations within prostate cells. When cells divide more quickly they make a greater number of genetic mistakes, some of which result in cancerous mutations. As well, more rapid cell division allows less time for DNA repair enzymes to correct these mutations. Normally, when cells make a genetic error to the DNA strand during cell division, the cell identifies that this has occurred and dispatches specialized DNA repair enzymes to correct these mistakes before they become permanent. However, during rapid cell division, as occurs from the influence of DHT, more DNA mistakes are likely to occur and it is less likely that the DNA repair enzymes will have sufficient time to fix any mistakes that may arise. For these reasons the build of DHT is linked to both prostate enlargement and prostate cancer. In fact, DHT is known to promote the spread of existing prostate cancer and males born with the genetic inability to synthesize (due to an inability to make the 5-alpha-reductase enzyme) DHT have been shown to be immune from developing prostate cancer during their lifetime. There is no question that DHT is linked to prostate cancer and prostate enlargement in a number of ways. In fact, DHT has also been shown to promote the production of free radicals within the prostate gland, which can directly cause cancerous mutations to occur to the DNA of prostate cells. So, the age-related escalation of DHT within the prostate gland is very undesirable, and may be one of the ways that nature attempts to kill us off once we, as men, have served our purpose of procreation. High levels of DHT within the prostate gland are linked to prostate enlargement, the development of prostate cancer and the spread of prostate cancer. Some experts believe that by age 40 all men should be putting in practice nutrition and supplementation practices that can protect the prostate from the build of DHT, and throughout their lifetime reduce free radical damage to prostate cells.
The encouraging news is that specific nutrients and natural bioactive compounds found in certain foods and natural supplements have been shown to block the conversion of testosterone to DHT and exert other protective effects within the prostate gland. As such, the consumption of these foods and supplements, at the correct dosage and/or standardized grade, have been shown to be effective in the treatment of enlarged prostate problems, and some of these natural agents are associated with the prevention of prostate cancer, and more recently have shown benefit in the management of some cases of prostate cancer.
Supplements that Block the Build Up of DHT
There are several known natural agents that can effectively block the build-up of DHT within the prostate gland. When taken in combination with each other, these supplements offer significant anti-aging benefits to the prostate gland, aimed at preventing and reversing prostate enlargement and helping to block certain steps in cancer development. The primary supplements for prostate support include the standardized grade of saw palmetto, pygeum africanum, beta-sitosterol, soy isoflavones and stinging nettle (urtica dioica).
Saw Palmetto – Saw Palmetto is a small palm tree that gives rise to berries, which contain various unsaturated fatty acids and sterols. Numerous studies have shown that these fatty acids and sterols block the conversion of testosterone to DHT and exert other favourable effects on prostate health. Unfortunately, saw palmetto berries contain only a 1.5% fatty acids and sterols, and so eating the berries is not likely to have a significant effect on prostate health. However, through an extraction process the fatty acids and sterols in these berries can be concentrated into a more potent saw palmetto extract supplement. Saw Palmetto extract supplementation has been shown to be a proven therapy for enlarged prostate problems and has recently been used in trials with prostate cancer patients. A systematic review of saw palmetto and its effects on treating enlarged prostate problems, was published in the Journal of the American Medical Association in the late 1990’s. After reviewing all the properly performed studies from around the world on this subject, the authors concluded that saw palmetto produces similar improvement in urinary tract symptoms and urinary flow as does the drug finesteride (also known as Proscar, which is used to treat enlarged prostate glands), and that compared to the drug finesteride, saw palmetto was associated with fewer adverse side effects. For example, erectile dysfunction rates are nearly 5% with finesteride use and approximately 1% for saw palmetto. For the treatment of benign prostatic hyperplasia (BPH) the usual dose is 160 mg, twice daily, of saw palmetto extract (standardized to 90% fatty acids and sterols) or 320 mg, twice per day, of a standardized grade containing 45% fatty acids and sterols. It may be prudent for all men 40 years and older to take this dosage of saw palmetto from an all-in-one prostate support formula, every day, to help prevent prostate enlargement and to help discourage the build up of DHT that is also linked to prostate cancer development and metastasis.
Pygeum Africanum – Pygeum Africanum, a natural agent derived from the bark of the pygeum africanum tree, contains active compounds known as triterpenes, which have also been shown to be effective in the treatment of enlarged prostate problems in numerous human studies. The usual dose of Pygeum for the prevention and treatment of enlarged prostate problems is 100-200 mg per day (std to 12-14% triterpenes). The active ingredients in pygeum africanum have been shown to reduce blood levels of leutinizing hormone, prolactin and the synthesis of cholesterol within the prostate. Together this produces an anti-aging effect on the prostate as the normal age-related increases in leutinizing hormone and prolactin encourage the uptake of testosterone by prostate cells and its subsequent conversion to DHT. Within the prostate the synthesis of cholesterol leads to a greater build of testosterone and DHT, as testosterone is made from cholesterol. By-products of cholesterol metabolism have also been shown to promote the degeneration of prostate cells, leading to prostate enlargement. Numerous studies have shown that pygeum africanum supplementation can reverse prostate enlargement problems via the actions mentioned here and therefore, should be included in an all-in-one prostate support supplement to help prevent age-related prostate problems by all men 40 years of age and older.
Beta-sitosterol – In recent years, prestigious medical journals such as the Lancet and the British Journal of Urology have published research papers demonstrating that beta-sitosterol (which occurs naturally in saw palmetto, soy products and in other plant foods) taken at a dosage of 20 mg, three times per day, or 65 mg, twice per day, is also extremely effective in reversing enlarge prostate problems. Beta-sitosterol is the most common sterol found in plant foods, and human observation (epidemiological studies) and experimental studies suggest that beta-sitosterol and other plant sterols (campesterol, stigmasterol) offer protection against colon, prostate and breast cancer. In regards to prostate problems, beta-sitosterol has been shown to inhibit the 5-alpha-reductase enzyme that converts testosterone into DHT, thereby reducing the build up of DHT within the prostate gland. Beta-sitosterol also blocks the formation of estrone hormone in fat cells, which is a form of estrogen that encourages the conversion of testosterone to DHT in the prostate, and prevents the removal of DHT by inhibiting its detoxification (via the hydroxylation pathway). Researchers suggest that these mechanisms of action provide the explanation through which beta-sitosterol supplementation has been effective in reversing enlarged prostate problems. Like the other nutrients mentioned in this section it should be incorporated into an all-in-one prostate support formula for men 40 years of age and older, to prevent and better manage these problems.
Soy Isoflavones – Contained within soy products, including soy extract, are several important isoflavones, the most important of which include genistein and diadzein. Genistein has been shown to directly inhibit the build up of DHT and exhibit many other biological properties that are related to the prevention of prostate disease and prostate enlargement as men age. Soy isoflavones have been shown to induce apoptosis (programmed cell death) of human prostate cancer cell lines, decrease androgen (testosterone and DHT) stimulation to the prostate gland, slow the cell division rate of prostate cells and prostate cancer cells, and reduce the conversion of androstenedione to estrone hormone in adipose tissue by acting as an aromatase enzyme inhibitor. All of these physiological effects are known to inhibit prostate cancer development and/or arrest prostate cancer growth. In Japan, where soy isoflavone intake is high (average intake is 50 mg per day), prostate cancer incidence is 80% lower than in North America.
Stinging Nettle – The herbal agent stinging nettle, (urtica dioica) also enjoys a reputation as a natural agent that has been used successfully to reverse prostate enlargement in European studies. Stinging nettle is a weed, whose aerial parts and roots contain its active ingredients, including specific flavonoids, sterols, lignans, fatty acids, polysaccharides, and lectins. Stinging nettle extract has been shown to block the action of DHT within prostate cells, by inhibiting the ability or DHT to bind to the nucleus of the cell, thereby blocking its ability to affect the cell’s DNA material. In turn, this prevents DHT from stimulating rapid cell division of prostate cells. Prostate combination formulas often include 20-60 mg of stinging nettle as part of the complex.
All-In-One Prostate Supplement
Many anti-aging experts feel that men 40 years of age and older should take an all-in-one prostate supplement every day that contains the natural agents discussed above, as an important measure to counter age-related changes that encourage the development of prostate enlargement and prostate cancer. Here is an example of a well-designed prostate support supplement:
Each capsule contains:
- Saw Palmetto – 320 mg (standardized to 45% fatty acids and sterols)
- Pygeum Africanum – 100 mg (standardized to 14% triterpenes)
- Beta-sitosterol – 65 mg
- Soy Extract – 100 mg (standardized to 10% isoflavone content)
- Stinging Nettle Extract – 30 mg (5:1 extract)
- Pumpkin Seed Extract – 25 mg
- Lycopene Powder – 12.5 mg
It may be prudent for all men 40 years of age and older to take 2 capsules per day. The same dosage is appropriate for the treatment of enlarged prostate problems.
Each year 200,000 American men are diagnosed with prostate cancer, and the disease kills 30,000 men annually. Those who survive face difficult treatment choices such as surgery or radiation, both of which do not always work, and commonly cause side effects, including impotence and incontinence. As such, men should do everything they can to try and prevent the development of prostate cancer in the first place, and in my opinion, that includes following the dietary strategies I have summarized at the end of this section and taking an all-in-one prostate support supplement, as outlined above. Canadian statistics indicate that one in every eight men is expected to develop prostate cancer in their lifetime, and one in four of them will die of it. Prostate cancer is the most common cancer in men, and the second leading cause of cancer in men, after lung cancer. In Canada up to 19,000 men are diagnosed with the disease each year, and numbers are expected to increase as the baby boomer generation of North American men enter the prostate cancer risk years (40 years and older).
Prostate cancer incidence increased in the U.S. steadily from 1981 to 1989, with a steep increase in the early 1990’s, followed by a decline. Incidence rates were forecasted to remain stable through the year 2001. However, the exaggerated rate of increase in the early 1990’s was transient and likely a result of increased early detection of preclinical prostate cancer due to widespread implementation of the new PSA (prostate specific antigen) blood-screening test. Nevertheless, prostate cancer remains the most frequently diagnosed cancer in North American men, as well as in other Western countries, accounting for 33% of cancers in men. One in eight men will develop prostate cancer during their lifetime, mostly after age 70, and one in 28 North American men will die from this disease.
As reported by W. Willet (1996) in the Journal of the National Cancer Institute, as much as 75% of prostate cancer may be prevented if men followed more prudent nutritional practices. Although prostate cancer is one of the most common cancers to affect men in Western countries (the leading cancer in U.S. and Canadian men), it is much less prevalent (up to 80% lower incidence) in Africa, Eastern Europe, and Japan. Dietary and lifestyle factors appear to influence the development of this disease as migration studies indicate that a marked increase in prostate (and breast) cancer incidence occurs in persons that migrate from low- to high-risk geographical areas. Another intriguing fact is that postmortem evaluation indicates that the prevalence of latent (existing, but not manifest) prostate cancer is similar between high- and low-risk populations, with genetic and lifestyle factors implicated in the progression to the malignant form of the disease. Thus, by age 45-50, 13 to 32% of men have cancer cells present within the prostate gland regardless of where they reside (Singapore-13% on men; Hong Kong-16% of men; Sweden-32% of men). However, in low risk regions these cancer cells tend not to undergo promotion and progression to a clinically significant malignant state, but rather tend to remain dormant and non-life threatening. It is argued that certain dietary behaviors are directly involved in preventing or encouraging the development of prostate cancer and/or the further progression of latent prostate cancer to a more life threatening, clinically significant form.
In Japan the incidence of clinically important prostate cancer is 80% lower than in North America. However, migration studies reveal that when men relocate from a low- to high-risk region of the world and abandon their traditional dietary patterns, their incidence of prostate cancer rises to approach that of North American men. Clearly the North American diet is fuelling high incidence of prostate cancer in the U.S, Canada, and other Western countries.
Diet, Lifestyle and Prostate Cancer
In recent years a number of nutritional and lifestyle factors have been identified that are strongly linked to the development of prostate cancer. The following represent the diet and lifestyle aspects that men should be aware of in regards to reducing their risk of prostate cancer.
Alcohol – In the year 2001, published data from the Harvard Alumni Study revealed that men with moderate liquor consumption (3 drinks per week to 3 drinks per day) show a 61-67% increased risk of developing prostate cancer compared to men who never or infrequently consumed alcohol. Wine and beer did not appear to be as hazardous as liquor, however men initiating alcohol consumption of any kind between 1977 and 1988 had a twofold increased risk of prostate cancer compared to men with almost no alcohol consumption at both evaluation dates (after controlling for other confounding variables). This study followed 7612 Harvard alumni (mean age – 66.6 years) from 1988 through 1993.
Heterocyclic Amines – Also in 2001, the study by K.T. Bogen and G.A. Keating provided evidence that higher intakes of heterocyclic amines among the U.S. Black population, especially from pan-fried meats, may partially explain the twofold increase in prostate cancer in this group, as U.S. Blacks were shown to consume approximately two- and approximately three-fold more heterocyclic amines at ages less than 16 and over 30, respectively. Black men are reported to have double the prostate cancer incidence as Caucasian men. Heterocyclic amines are potent mutagens that increase the rates of colon, mammary, prostate and other cancers in rodents. (6)
Indole-3-Carbinol and Cruciferous Vegetables – In the journal Oncogene, SR Chinni and fellow researchers, provided strong evidence to show that the indole ring structures present in cruciferous vegetables may play an important role in the prevention of prostate cancer. This study demonstrated that indole rings (indole-3-carbinol) can inhibit the growth of PC-3-type human prostate cancer cells by arresting their cell division cycle and promotes their demise through apoptosis (programmed cell death). They conclude that indole-3-carbinol may be an effective chemo preventive (an agent that prevents cancer) or therapeutic agent against prostate cancer. Previously, similar findings have argued for the ingestion of indole-3-carbinol as a means to prevent breast cancer in women. Indole-3-carbinol and related compounds are common constituents of cruciferous vegetables such as broccoli, brussell sprouts, cabbage, cauliflower, bok choy and turnips. If possible, cruciferous vegetables should be consumed daily to help prevent many types of cancer.
Aerobic Fitness and Blood Pressure – As well, a link between vascular disease and increased risk of prostate cancer has been reported recently suggesting that heightened central sympathetic stimulation, which can lead to elevated blood pressure and heart rate, also may over-stimulate the androgen activity of prostate cells. Increased androgen activity is strongly linked to prostate cancer. Thus, heart rate and blood pressure may represent indirect markers of sympathetic stimulation of androgen activity on the prostate. In support of this model, recent data (2001) from the Cardiovascular Health Study (n=2442 men) demonstrated that men with a resting heart rate equal to or greater than 80 beats per minute had a 60% greater chance of developing prostate cancer, during the 5.6-year follow-up period, compared to men with a resting heart rate of less than 60 beats per minute, an indirect indicator of cardiovascular fitness and lower sympathetic tone. Thus, a moderate to high level of aerobic fitness appears to offer some protection against prostate cancer as well.
Saturated Fat – A number of studies have shown that a high animal fat diet is strongly linked to an increased risk of developing prostate cancer, probably as a result of the fact that higher intakes of saturated fat promote the over secretion of testosterone. As such, consuming only low-fat animal products, as outlined in the core program of this book, is also advantageous as a means to help prevent prostate cancer. It is noteworthy that Asian men, living in Asia have a 2% lifetime risk of prostate cancer, but when they move to North America and adopt our high animal fat style of eating the lifetime risk rises to 10% in the next generation.
Omega-3 Fats – In contrast to the damaging effects of saturated fat on prostate cancer development, omega-3 fats have been shown to inhibit the growth of prostate cancer in number of experimental studies. A study published in The Lancet (June 2, 2001) demonstrated that in a population of 6,000 Swedish men, those who regularly consumed fish (salmon, sardines, herring, mackerel – rich in omega-3 fats) showed a 33% reduction in prostate cancer risk during the 30 year follow up period, compared to men who ate no fish.
Soy Intake and Isoflavones – Higher intakes of soy products have consistently been shown to be associated with a marked reduction in prostate cancer incidence. A recent study using modern analytical technology to analyze dietary intakes of individual phytoestrogens in patients with prostate cancer or control subjects (cancer-free) indicated a significant protective effect of the soy isoflavones genistein and diadzein, as well as the phytoestrogen coumestrol.
Research in this area reveals that there are at least seven modes of action through which soy isoflavones (genistein and diadzein) may defend against prostate cancer:
1. Anti-proliferative-soy isoflavones have been shown to inhibit two key enzymes within prostate cancer cells that trigger cell division and growth. These two enzymes include protein tyrosine kinase and topoismerase II. By blocking their activity soy isoflavones have demonstrated an impressive ability to greatly inhibit the growth and division of prostate cancer cells under experimental conditions.
2. Increase sex hormone-binding globulin-soy isoflavones stimulate the synthesis of sex hormone-binding globulin in vivo, thus reducing the plasma concentration of free, unbound sex hormones. As a result there is less available (unbound) testosterone and other steroid compounds that are free to bind to prostate receptors and exert their potentially hyperproliferative effects. It is well established that certain androgens and estrogens are linked to the progression and promotion of prostate cancer and higher serum levels of sex hormone-binding globulin is associated with a reduced risk of many hormone dependent cancers.
3. Decreased steroid hormone synthesis-soy isoflavones have demonstrated the ability to help block the over production of certain steroid hormones that influence the promotion and progression of prostate cancer. Specifically, soy isoflavones are known to inhibit 5 alpha-reductase, aromatase (estrogen synthase) and the 17 beta-hydroxysteroid deydrogenase enzymes, which in turn block the synthesis (to an appreciable degree) of dihydrotestosterone, estrone and other steroid hormones, respectively. Dihydrotestosterone is known to enhance prostate cell division (including cancer cells) and is directly linked to the promotion and progression of prostate cancer in humans. The over production of estrogen hormone from adipose tissue is also associated with increased prostate cell proliferation and prostate cancer.
4. Antioxidant function-genistein, the most intensively researched soy isoflavoinoid, also acts as a cellular antioxidant. As soy isoflavones are known to concentrate within prostatic fluids (at higher values than in plasma), they are considered to be an important defense against free radical damage and the cancerous mutations that are known to arise from free radical damage to prostate cells.
5. Apoptosis or Programmed Cell Death: Soy isoflavones have also been shown to selectively encourage prostate cancer cells to undergo programmed cell death (apoptosis). In particular genistein has been shown to inhibit cell growth and induce apoptosis by modulating transforming growth factor-beta signaling pathways. This effect has been clearly shown with both LNCaP and PC-3 human prostate cancer cell lines.
6. Anti-angiogenisis: Soy isoflavones demonstrate an ability to hinder the ability of cancer cells from growing the necessary capillaries that feed their growth as they attempt to spread (metastasize) to adjacent tissues. It appears that genistein, in particular, blocks the synthesis and/or release of growth factors required to form the extensive network of blood vessels necessary to aid the spread of the malignancy.
7. Androgen blockade: Soy isoflavones bind to androgen and estrogen receptors on the prostate gland, partially blocking access to the cell of testosterone, estrone and related hormone modulators of prostate cell (and prostate cancer cell) growth. The net effect appears to be a down-regulation influence whereby the growth and cell division rate of prostate cells is slowed and any existing prostate cancer cells are subjected to less of a stimulatory influence from various androgens and estrogens (due to lower intracellular concentrations). This effect is readily apparent from studies that demonstrate that genistein inhibits the growth of benign prostate hypertrophy, prostate cancer tissue in histoculture and growth of tumor cell implants in rats.
By all accounts sufficient evidence now exists to encourage the more frequent consumption of foods, supplements and nutraceuticals that are a rich source of soy isoflavones as a means to help prevent prostate cancer. Moreover, soy isoflavones may also be considered not only in a chemo preventive role, but possibly as chemotherapeutic agents as well. A recent report in the scientific literature indicated that in a case study, a 66-year old prostate cancer patient took a phytoestrogens supplement (160 mg per day) for one week before radical prostatectomy. On histological examination of the prostatectomy specimen, a significant shrinkage of the tumour mass was noted (apoptosis in tumour cells) suggestive of tumour regression, compared with the preoperative needle biopsy.
From the stand point of prostate cancer prevention the traditional Asian diet contains an average isoflavone content of 50mg per day. Epidemiological data (Observational data) indicate that the incidence of clinically important prostate cancer is 80% less in Japan, than in Canada and the United States.
The body of evidence strongly suggests that men should consume sufficient soy products on a daily basis to yield a minimum of 50 mg of isoflavones as one means of prostate cancer chemoprevention. Soy isoflavones can be consumed from soy-based foods, supplements containing soy extract, and various soy-based functional foods (e.g. soy protein shake mix).
Studies indicate that prostate cancer may also arise from free radical damage to prostate cells, converting them into mutated, cancer cells. Evidence is very strong to suggest that the antioxidant lycopene (derived especially from tomatoes), plays an essential role in protecting prostate cells from free radical damage. Lycopene is known to concentrate in the prostate gland and its fluids, at levels much higher than are found in the bloodstream. As such, it has been shown to be a tissue-specific antioxidant in prostate health. Human studies such as the Physicians’ Health Study and the Health Professionals’ Follow Up Study have shown a striking correlation between higher lycopene blood levels and/or intake levels (6.5 mg per day or more), and a marked reduction in prostate cancer development (as much as a 40% reduction). Experimental evidence also strongly supports the protective effect of lycopene against prostate cancer. Note that other sources of lycopene include guava, papaya, red grapefruit and watermelon. Lycopene is a fat-soluble antioxidant (a sister compound to beta-carotene) and therefore there must be some fat present in the stomach in order to absorb it. Thus, no lycopene is absorbed if you eat a red grapefruit, guava, watermelon, papaya or tomatoes without consuming some fat at the same time. This is why the lycopene found in tomato sauces was associated with a reduced risk of prostate cancer in the Health Professionals Follow Up Study, whereas the consumption of tomato juice on an empty stomach was not shown to be protective. So, if you eat these foods make sure you consume a bit a fat at the same time in order to maximize your absorption of lycopene.
Soy isoflavones (mentioned earlier in this review) are also known to provide antioxidant protection to the prostate gland, and soy intake is highly correlated with reduced prostate cancer development in epidemiological and experimental studies.
There has also been the suggestion from human intervention trials (placebo-controlled) that vitamin E supplementation (60 IU per day) and selenium (200 mcg per day) supplementation provides antioxidant support to the prostate, resulting in a 40-50% reduction in risk of prostate cancer according to two recent intervention trials.
Other Prostate Protective Nutrients
Zinc – The prostate gland contains a higher concentration of zinc than any other organ in the body. Zinc is required to maintain semen volume and testosterone synthesis. Some studies show that men with prostate enlargement have lower levels of zinc in their prostate gland. This is though to be due to the fact that zinc inhibits the 5-alpha-reductase enzyme that converts testosterone into DHT. Moderate zinc supplementation has been shown to help reverse prostate enlargement. Unfortunately, the average intake of zinc from food is 8-9 mg per day. Experts suggest that a total daily zinc intake per day of 25- 30 mg is associated with more optimal health, including the prevention and management of prostate enlargement. Thus, the intake of 15 mg of zinc per day from a high-potency multiple vitamin and mineral supplement is part of a prudent strategy for prostate health.
Vitamin D – Human observational studies (Epidemiological studies) have shown that where year round sunlight intensity is low, the rate of prostate cancer is high. In North America the incidence of prostate cancer is much higher in regions above the 40th degree latitude, which essential divides the United States in half from north to south. This phenomenon, which has also been shown for breast cancer and colon cancer, has been attributable to low blood levels of vitamin D in as much as direct sunlight exposure to our skin is required for the body to make vitamin D. As such, populations living further from the equator as you travel north or south, show lower year round blood levels of vitamin D, and a higher incidence of prostate cancer, breast cancer and colon cancer than populations living closer to the equator.
Prostate cells and prostate cancer cells have been shown to have receptors for the binding of vitamin D. When vitamin D in the bloodstream enters prostate cells through these receptors, prostate cells convert vitamin D to a more powerful form of vitamin D, known as 1,25 dihydroxy vitamin D (prostate cells convert 25-hydroxy vitamin into the more potent 1,25 dihydroxy vitamin D). In the form of 1,25 dihydroxy vitamin D, this form of vitamin D promotes the full maturation of prostate cells and slows down the rate of cell replication. This, in turn, reduces risk of prostate enlargement and prostate cancer development. Vitamin D exerts similar effects on breast cells and colon cells, thereby reducing the risk of cancer of these tissues as well. Experimental and animal studies have shown that in some types of prostate cancer the administration of vitamin D can transform malignant cancer cells back to more normal looking prostate cells, inhibit prostate cancer cell replication and suppress their life threatening cancerous behaviours and metastasis. Several preliminary studies have been carried out on human prostate cancer patients who have been given high doses of various forms of vitamin D. Although some of the results were encouraging it is too soon to know the degree to which high dose vitamin D supplementation (2,000 IU per day) may be useful as an adjunct to prostate cancer treatment. However, as means to help prevent prostate cancer it is prudent to ingest a high potency multiple vitamin and mineral each day that contains 400 IU of vitamin D. As a rule, each 400 IU of vitamin D one consumes elevates blood levels of vitamin D by 40 nanomoles per L (nmol/L). It is not uncommon to see low blood levels of vitamin D in the range of 15-45 nmol/L in individuals living in the northern parts of the United States as well across Canada. With respect to the prevention of cancer studies suggest that blood levels of vitamin D should at least be in the range of 85-110 nmol/L, which is also ideal for the prevention of osteoporosis. Thus, men over the age of 40, who live in these high risk regions of North America should consider taking an additional 400-600 IU of vitamin D each day, especially from October to May, when there is insufficient sunlight intensity and casual sunlight exposure to help maintain more optimal vitamin D blood levels.
Protecting the Prostate
To help combat the age-related changes to the prostate gland that lead to problems of enlargement and the multi-step processes involved in prostate cancer development, all men should practice prudent nutritional practices throughout their lifetime. Due to the changes that occur at around age 40, men this age and older may consider taking a supplement that contains the correct dosage and standardized grade of saw palmetto, pygeum africanum, beta-sitosterol, soy isoflavones, stinging nettle, lycopene and other prostate-related nutrients as a form of chemoprevention and for general prostate gland support. The current scientific evidence suggests that the following nutrition and lifestyle factors can favourably affect prostate health and counter the age-related changes that promote prostate enlargement and prostate cancer. The following recommendations should be strongly considered by all men throughout their lifetime:
1. Consume a diet that is low in saturated fat.
2. Remain at or near your ideal body weight.
3. Consume alcohol in moderation or not at all.
4. Consume tomato and tomato products on a daily basis, as well as other lycopene-containing fruits and vegetables.
5. Use more soy products, such as tofu, veggie burgers, miso soup, soy nuts and soymilk.
6. By age 40, consider taking an all-in-one prostate support supplement that contains the herbal ingredients outlined previously in this program. It is vital that the herbal and accessory compounds are present at the correct dosage and standardized grades, in order to yield sufficient amounts of their bioactive agents to be effective.
7. Take a high potency multi vitamin and mineral that is enriched with the following antioxidant levels: vitamin E (400 IU), selenium (100-200 mcg), vitamin C (1000 mg), as well as 15 mg of zinc and 400 IU of vitamin D.
8. Ingest cruciferous vegetables a minimum of 3-5 times per week.
9. Remain fit, especially from a cardiovascular fitness standpoint, striving to achieve a resting heart rate of below 60 beats per minute.
10. Avoid pan-fried meats and other sources of heterocyclic amines (charred BBQ meats and blackened fish and meats).
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