Xenoestrogens

I don't know if this is a good thing or not, but given that I've written so many articles about estrogen, I'm starting to get calls from Ladies Home Journal and Redbook to join their editorial staff. They must figure that it's nice that a young man would be so interested in estrogen as opposed to that nasty hormone, Testosterone!

Well, the calls are probably going to increase because I'm at it again. And the more I look into estrogens, and in particular, environmental extrogens or xenoestrogens, the more apprehensive I get. Hell, I'll be surprised if by the end of this decade we don't all have sperm counts that rival the eunuchs that guard a harem.

For those of you who are new to the site, or who haven't a clue what I'm talking about, there are certain chemicals (the aforementioned xenoestrogens) that could have detrimental effects on your physique and health. These chemicals have been shown to interfere with the synthesis, release, transport, action, storage, elimination and binding of endogenous hormones.(1)

Any way you look at it, this isn't a good thing. More specifically though, these chemicals interfere with Testosterone – our favorite hormone – while possessing estrogen-like properties. Some of these compounds may even be more potent than estrogen in terms of activating transcription.

So, what does this ultimately lead to? How about lowered Testosterone levels, increased estrogen levels, testicular cancer, and prostate cancer and hypertrophy just to name a few.(2-9) Heck, the estrogen-like effects and reduction in Testosterone – or interference with the way Testosterone works by binding to T-receptors – caused by these chemicals can be enough to have some adverse effects on your body composition. This could include increased body fat, reduced muscle mass, and even a decrease in strength.(10)

Yeah, yeah, plus there's that health thing. Xenoestrogens have even been shown to have negative effects on the immune system.(11) They can even affect the nervous system by passing through the blood-brain barrier, thus mucking up memory, behavior, and the ability to learn (12).

In the following paragraphs, I'm going to go over each of the most common chemicals or classes of chemicals found in our environment and how to avoid them or at least combat their effects. First however, I'm going into a long, detailed review of how these chemicals exert their effects and all of that other good stuff. Kidding. I'll try to make it quick.

A Quick Review

Let's discuss how and why these chemicals are able to exert these effects on out bodies. First off, these chemicals can remain in the environment for years and years (some having half-lives of 25-100 years), thus keeping exposure constant.

Unfortunately, these chemicals can enter our bodies in many ways; either through ingestion, inhalation, or even absorbed through the skin, as is the case with cosmetics. Once these chemicals are in our body, they're often able to bypass our liver. Once this occurs, they can be stored in our fat tissues because most of them are lipophilic (meaning they are attracted to fat).

Over time, this can lead to high levels of these chemicals being stored in our body. Not only that, but when fat is mobilized for fuel, like when we exercise, these chemicals are consequently released into our bloodstream. This is bad.

Normally, if this were a "natural" hormone like estradiol or something of that nature, your body could use sex hormone binding globulin (SHBG) to reduce the concentration of the hormone that would actually bind to receptors. However, xenoestrogens have been shown not to bind very well – -if at all – to SHBG, therefore leaving a large amount of the chemical around to bind with receptors and initiate protein transcription.(13)

Also, once these xenoestrogens are in the body, they could bind to androgen receptors (AR), thus blocking androgens like Testosterone from binding to the same receptors. Testosterone would seek out its usual parking spot, only to find some putz already in it! In this way, these xenoestrogens can act like anti-androgens.

Of course, as I explained before, these bad guy, or should I say, bad "girl" chemicals can bind to estrogen receptors (ER) as well. They, however, might activate protein transcription to a greater degree than estradiol. Even worse, they might do their mischief (initating protein transcription) while allowing estradiol or even another xenoestrogen to exert its effects as well. This could be considered an additive effect.

Normally, something that binds to the estrogen receptor (the alpha receptor is what we're concerned with) will block anything else from binding, as is the case with tamoxifen. However, these xenoestrogens exert their effects and allow estrogen to pass right on through as well. They sit in estrogen's "parking lot," but for some reason, they allow other "cars" to pass through their spot, almost as if they were invisible!

If this weren't bad enough, a synergistic effect can sometimes be seen with different xenoestrogens. In other words, the combination of two chemicals could result in one accentuating the effects of the other!(14,15,16,17)

Some of these chemicals can even affect the production or release of hormones like Testosterone or even thyroid hormones. Some can even affect the normal metabolism of estradiol, thus producing metabolites that are more estrogenic than they normally would be otherwise.

As I stated earlier, all of this can spell increased body fat, decreased strength and muscle mass, an impaired immune system, and so on. The list isn't short. For more info on the subject, check out my article, "The War on Estrogen."

The Villians

The following paragraphs list classes of chemicals that we need to be wary of, or at least aware of.

Pesticides

The following compounds can enter your body by ingesting foods that were sprayed with them or somehow came into contact with them. They can also be inhaled, or they can even find their way into water. And, it's actually been found that floors of households that have cats or dogs are veritable hotbeds of pesticides as the little furry beasties track the stuff in on their paws.

DDT – While this chemical has been banned for a while in the US, its ability to be stored in body fat has caused some concerns as even small amounts can still have detrimental effects. So what can this compound do? Well, a metabolite of DDT can inhibit androgens from binding to the androgen receptor, thus preventing androgen-induced transcription. (Again, the chemical can take Testosterone's, or any steroid's, parking spot.) This could mean a decreased effectiveness with any androgen that exerts its effects via the AR.(18)

Procymidone – Another common pesticide that's also able to prevent androgens from binding to the AR.(19)

Vinclozolin – Ditto. (20,21)

Dimethoate – This insecticide has been shown to lower T4 and negatively affect thyroid metabolism in general. It can also cause sperm and testicular damage. And, as you might guess, it can also lower Testosterone levels.(22,23,24)

Trichlorfon – This is yet another organophosphate insecticide like Dimethoate. It has been shown to damage immune system function in men.(25)

Metiram – This pesticide can reduce thyroid hormone levels.(26)

(Hell, and you thought this stuff only killed bugs!)

Alkylphenolics

These compounds can be found in detergents, surfactants, paints, shampoos, spermicidal lubricants (nonoxynol-9), cosmetics, drinking water, and can enter the body via inhalation and even ingestion from pesticide sprays.

These compounds were shown to be estrogenic long ago. They've also been shown to cause growth of cultured breast cells taken from humans.(27,28,29)

Phthalates

These compounds can be found in many things, but are mostly associated with plastics. Common culprits include plastic food wrap, ink on plastic, vinyl floors, emulsion paint, cheese, milk, eggs, meat, water, hell, even baby teethers. Not that any of us use them. Well, with the exception of John Berardi who chews on them in-between sets.

If this class of chemicals wasn't bad enough on its own, they're also lipophilic, which makes them great candidates to be stored in fatty foods as well as in your own body fat.

They've been shown to activate protein transcription after first binding to the estrogen receptors in breast tissue. That means they're great for growing breasts, regardless of whether you're a man or a woman. They also posses potent anti-androgenic activity and are toxic to testicular cells.(15,30,31)

Bisphenol A

This compound can be found in cans used for foods and infant formulas, plastic storage containers, and even baby bottles. Actually, it can be found in most plastic bottles and even dental sealant.

As far as negative effects go, it's been shown to cause the growth of MCF-7 human breast cancer cells, and that means it's estrogenic. It's also demonstrated potent anti-androgenic activity similar to that of phthalates.(30,32)

Brominated Flame Retardants

These chemicals can be found in many household appliances such as televisions, computers, and other electrical devices that are prone to causing fires. While they might have a hard time getting into your system, it still makes you wonder. Especially if you like to have sex on top of the TV.

As far as effects go, they can negatively affect thyroid hormones and can even impair memory and learning. They've also been shown to cause growth of cancerous breast cells.(33,34)

PCBs

Polychlorinated biphenyls, or PCBs, can be found in fire retardants, adhesives, waxes, and as heat transfer fluids in large transformers and in capacitors. They remain in our environment a long time because they're very resistant to breakdown and are very soluble in fat. That means our fat, too.

These substances have been shown to be very effective at mimicking estrogen. Not only that, but they've even been tied to reduced IQ and development in children.(35,36)

Parabens

These chemicals are used in perfumes, toothpaste, and certain cosmetics. They even seem to exist in air fresheners. Like the others, they're estrogenic.(37)

If all this wasn't bad enough, all of these xenoestrogens can activate the ER alpha, and that could cause breast tissue growth, in addition to cancer.(38-46)

Estrogen Cocktails?

We've talked about how estrogen-like compounds can find there way into our bodies via inhalation, ingestion, absorption, etc. However, is it possible that actual estrogens like estradiol could find their way into our food or drinks? The answer appears to be yes.

Numerous studies have found estrogen and progesterone to be present in dairy products, including milk. Even though most of the estrogens were bound, there's still enough free hormone present that could possibly have some adverse effects on the body. However, you'd probably have to drink at least a few gallons of milk before you'd have to worry about it. So unless you're a milk freak, I doubt there's any real worry.

Also, it appears that the higher the fat content, the higher the hormone concentration. So, it might be a good idea to stay away from whole milk and full-fat cheese.(47-51)

Luckily, we've still got plain old water....or so I thought. It turns out that cojugated estrogens excreted by women in their urine are "reactivated" by bacteria in sewage. Both natural and synthetic forms of estrogen and progesterone have been found in drinking water.(52,53)

Protect Yourself

The last thing to discuss, of course, is how to minimize or eliminate exposure and if exposure is impossible to avoid, a way to reduce the negative effects.

As far as the drinking water goes, there are a few options. It seems that regardless of which type of water you drink, you're going to get some type of estrogen or estrogen mimicking compound in it. For instance, reverse osmosis will remove cadmium (also a xenoestrogen). Conventional water treatment, however, did not remove estrogens found in drinking water. But, chlorine and ozone treatment did mitigate the problem.

For the most part however, conventional treatment will not remove most of these chemicals. So, water treated through reverse osmosis or via ozonation or activated carbon, which is probably the best treatment, may be better in most cases.(54,55)

Some bottled waters might be better, but unfortunately, they come in plastic bottles, many of which contain Bisphenol A.

Here are some tips on how to avoid exposure to the compounds mentioned earlier:

• Use water-based paints to avoid alkylphenolics

• Make sure that the teething toys you have are PVC-free. Otherwise, they could contain phthalates.

• If you're really concerned with certain fruits or vegetables being contaminated with pesticides, opt for organic food instead. Other than that, washing the fruit or vegetable thoroughly can help too. Still it doesn't guarantee complete elimination.

• Plastic utensils, baby bottles and even things like beakers that are scratched can leak chemicals like Bisphenol A. Replace those that are damaged with new products.

• Perfumes and air fresheners, along with other scented products may contain parabens. Luckily, perfumes should list their ingredients, so you can check for parabens and choose a product that doesn't contain them. Other than that, try cutting down on air freshener usage.

• One last thing that may work would be to use some type of anti-estrogenic compound like clomiphene or tamoxifen. Isoflavonoids have been shown to block environmental estrogens from inducing any growth in humans breast cancer cells.(56) Since these weaker compounds can provide some protection, it stands to reason that clomiphene or tamoxifen should do the same.

I'd actually rather see these two latter compounds used instead, as there are some studies suggesting that many isoflavonoids can induce protein transcription after binding to alpha receptors.

Something along the lines of 25 mg of clomiphene every day to every other day might well do the job. In other words, it wouldn't require a very large dose. Besides, clomiphene would help to combat not only the risk of breast tissue growth and cancer, but it can help prevent the xenoestrogen-caused reduction in Testosterone.

Conclusion

I realize that it's hard to avoid most of these compounds as we all have to step outside of the house here and there to urinate. Oh wait, that's me. Nevermind. Try to follow the tips I've given you and I'd suggest that you consider using clomiphene as a possible way to combat the negative effects caused by xenoestrogens.

Other than that, looking at the labels on products may help, too. Hopefully the government will step in and force these manufacturers to get rid of at least some of these chemicals. For the time being, however, try to follow the info I've given you, but don't do anything rash. For instance, you do need water in order to live! So don't stop ingesting water or any other liquids and say I told you to. Just make whatever adjustments that seem reasonable to you and carry on. Good luck!

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