
Milk Thistle Can Cure Psoriasis But It Is Very Estrogenic And May Cause Gynecomastia

There is a lot of liver supplements useful in psoriasis and one of the most promoted and recommended is Silymarin extracted from Milk Thistle seeds. The positive effects of the active ingredient(s) silymarin are well known and scientifically proved as being a potent antioxidant and effective especially in liver problems. Psoriasis is one of the health issues that can be markedly improved by silymarin but is it really worth to take Milk Thistle extract to help your liver?
Most people are well aware of the effects of some of the soy isoflavones (Genistein and Daidzein) which act as the estrogens in the body. There is a big hype regarding the soy being the biggest estrogenic evil and many people avoid soy even in trace amounts which is silly in my opinion. When saying in trace amounts I am not talking about eating the soy foods like tofu, tempeh, natto and miso.
I am talking about the soy lecithin which is actually a highly concentrated extract of some beneficial nutrients found in soy. Taking the soy lecithin is nothing like eating the whole food soy or common processed soy products.
However, we still have an option in taking the sunflower lecithin instead.
On the other hand the same people who avoid soy as hell take the silymarin supplements which are the highly concentrated extracts of estrogenic compounds found in Milk Thistle.
Don’t you believe?
Estrogenic Milk Thistle extract for Psoriasis?
Here is a testimony of guy who took 1 tablet of Milk Thistle extract for several months and developed gynecomastia.
”
I took Milk Thistle extract (175 mg of the 80% standardized extract) daily for several months to help with liver function and developed gynecomastia (no, I never used steroids). Many other men have experienced this side effect as well, just google ‘Milk Thistle gynecomastia’.
If you are a male, I strongly suggest you consider other sources of anti-oxidants or different supplements for liver support.
“
Source Link: https://www.erowid.org/experiences/exp.php?ID=98457
Use of Milk Thistle for liver support is very popular in bodybuilding community, especially in those who use the anabolic steroids which are very hard on the liver.
The bodybuilders may not be affected by Milk Thistle supplements as much due to the fact that they take the aromatase inhibitors which if taken in high doses may almost completely shutdown the natural (and beneficial) production of estrogens. The Anastrozole (an aromatase inhibitor) is capable to inhibit the aromatase enzymes about 97% when taken 1mg daily. [12]

Image Source: https://en.wikipedia.org/wiki/User:Boghog
Some drugs like Tamoxifen (which is also a popular drug in bodybuilding) act directly on estrogen receptors thus may block the estrogenic effects of silymarin (which is an Estrogen receptor Beta agonist). [10,11]
Tamoxifen (brand name Nolvadex) is the drug which is a selective estrogen-receptor modulator and inhibits also the aromatase enzyme which is responsible for conversion of testosterone to estrogen.
The aromatase inhibitors work via inhibition of conversion of hormones like testosterone to estrogens and have no effect on exogenous (administered substance – not produced in the body) estrogenic substances like those found in Milk Thistle!
Some bodybuilders abusing the anabolic steroids have their breast glands removed in order to avoid the gynecomastia.
Average levels of Estradiol in men and women
Estradiol just like the testosterone in the other hand are naturally produced in both men and women.
Estradiol is the most potent form of estrogen produced in the body.
The ratio and total levels of these hormones is what really matters in order to make women look, behave and function as women and to make man look, behave and function as men.
”
The normal range of estradiol levels found in fertile men was 10–82 pg/ml.
” [9]
However, the reference range of estradiol in men is between 10–40 pg/mL.
In women the levels of estradiol vary throughout the menstrual cycle from almost 0 pg/mL up to 400 pg/mL or even more.

Image Source: Häggström, Mikael (2014). “Reference ranges for estradiol, progesterone, luteinizing hormone and follicle-stimulating hormone during the menstrual cycle”. Wikiversity Journal of Medicine 1 (1).
Silymarin in rats proved to have significant estrogenic effects
The study in mice found out that an androgen receptor is involved in development and maintenance of male sexual differentiation (characteristics of male). [5, 6]
Androgen receptor “can have significant effects on many aspects of physiological functions and disease progression, such as immune function, metabolism, and tumorigenesis.” [5]
Silymarin was proved to be able to inhibit the androgen receptors and thus negatively affect the prostate cancer cells.[7]
Even though silymarin may have a positive effect on prostate cancer cells, the effects of silymarin administration to healthy male may have the negative effects.
One of the most interesting studies there is regarding the estrogenic effects of Silymarin was published by scientists in 2001. The study “Estrogenic effects of silymarin in ovariectomized rats” concluded that Silymarin estrogenicity is about 10 000 to 25 000 weaker than estrogen hormone – 17Beta-estradiol – which is naturally produced in human body in both sexes. Scientists consider the estrogenicity of silymarin comparable to isoflavones – genistein and daidzein – which are abundantly found in soy. [8]
Silymarin administration for 30 days at dosages of 25mg/day and 50mg/day significantly increased the uterine weight, luminal epithelium height and endometrium height in rats.To compare the silymarin effects to estradiol the researchers administered the other group of rats 5 mcg of estradiol daily for the last 3 days.
Image Source: Kummer V, Mašková J, Čanderle J, Zralý Z, Neča J, Machala M. Estrogenic effects of silymarin in ovariectomized rats. Vet. Med-Czech 46, 2001 (1): 17-23[8]
Silymarin administration significantly affected the levels of Thyroid hormones in rats after 30 days of treatment. To compare the silymarin effects to estradiol the researchers administered the other group of rats 5 mcg of estradiol daily for the last 3 days. Image Source: Kummer V, Mašková J, Čanderle J, Zralý Z, Neča J, Machala M. Estrogenic effects of silymarin in ovariectomized rats. Vet. Med-Czech 46, 2001 (1): 17-23[8]” width=”694″ height=”182″ />
Silymarin administration significantly affected the levels of Thyroid hormones in rats after 30 days of treatment.To compare the silymarin effects to estradiol the researchers administered the other group of rats 5 mcg of estradiol daily for the last 3 days.
Image Source: Kummer V, Mašková J, Čanderle J, Zralý Z, Neča J, Machala M. Estrogenic effects of silymarin in ovariectomized rats. Vet. Med-Czech 46, 2001 (1): 17-23[8]
The another study confirmed that micronized silymarin supplement Silymarin BIO-C is proved to cause the hyperprolactinemia in female rats.[2]
A 14 days treatment with Silymarin BIO-C at dosages of 25 mg/kg and 200 mg/kg administered orally dose dependently increased the serum prolactin levels.
And “after a 66-day discontinuation of Silymarin BIO-C treatment, prolactin levels were still significantly elevated although we observed a trend to decrease that was counteracted by a further 7-day treatment with Silymarin BIO-C. Bromocriptine, a dopamine D(2) receptor agonist, (1-10mg/kg, os) significantly and in a dose dependent manner, reduced the serum prolactin levels; bromocriptine, at the dose of 1mg/kg, significantly reduced the high serum prolactin levels induced by Silymarin BIO-C.” [2]
Milk Thistle in cows proved to increase milk production
The researchers confirmed the milk production increasing effects of Milk Thistle also in cows.
”
Two comparative trials were performed, each with 16 cows which in the period of 2-6 weeks after parturition…
…
The cows of test groups were given for a fortnight feed rations containing a meal of milk thistle (Silybum marianum, L., Gaert.) seeds, at a rate of 0.3 kg per head/day with the contents of 2.34% silybin and silydianin (substances of the so called silymarin complex of the flavonolignane group).
…
Milk production in the cows of control groups was decreasing during the trial (up to P 0.01), but in the test cows it was higher by 7.7% (trial 1) and by 3.4% (trial 2), in comparison with the milk yield at the beginning of the trials. Differences in metabolism parameters and milk production in favour of the cows which were given milk thistle in their feed rations were observed even in a fortnight after the diet stopped to contain this ingredient.
” [4]
If you want to compare the dosage of 300 grams (0.3 kg) of Milk Thistle seeds to capsules of Milk Thistle extract you may buy as supplement it is like seventy 150 mg capsules of 80% silymarin extract (containing 120 mg of silymarin per capsule).
Sure, this may seem like a really high dosage but whole Milk Thistle seeds are harder to assimilate than extract in capsules which is highly processed to make it bioavailable.
Also the weight of cows is about 1400 lbs on average (635 kg).
If we compared the dosage to average 200 lbs (90 kg) human we would get the equivalent of 10 capsules (150 mg of 80% Milk Thistle extract per capsule). This does not seem so much, is is like eating 43 grams of Milk Thistle seeds.
Milk Thistle in women increases the milk production
The Milk Thistle effects on breast (growth) and lactation is nothing new. In folk medicine Milk Thistle was used for ages to support the milk production in lactating women. [1]
”
Women orally treated for 63 days with Silymarin showed a clear galactagogue role for the product with an increase of 85.94% of the daily milk production (placebo: +32.09%). No drop out, nor unwanted effects were reported in both groups. Compliance and tolerability were also very good.
…
Silymarin may be considered as a safe and effective herbal product that can be orally administered in order to improve the daily milk production in healthy women after delivery, without affecting milk quality.
” [3]
And here is another experience of male who took the Milk Thistle extract.
”
I’ve been preeloading milk thistle (I have 175mg caps – standardised to contain 80% silymarin, 140mg – so been taking 6 caps/day) for about a week now…
…
The problem being I have noticed my nipples getting puffy and think it may be starting gyno issues?
…
Anyone ever experienced such when taking Milk thistle?
“
If a healthy woman produces 70 mcg – 500 mcg of estradiol naturally every day (the amount depends on phase of menstrual cycle) then taking 4 capsules of Silymarin (considering 1 capsule of 175 mg of 80% standardized Silymarin = 140mg of Silymarin) would be like getting the lowest daily production of estradiol of healthy woman.
70 mcg = 0,07 mg (estradiol)
140 000 mcg = 140 mg (silymarin)
70 mcg x 10 000 = 700 000 mcg (in order to compare the effects of Silymarin we need to multiply the dosage of estradiol x 10 000)
(140 000 mcg / 700 000 mcg) * 100 (%) = 20%
One capsule containing the 140 mg of silymarin is comparable to 20% of daily production of estradiol in healthy woman.
Please, keep in mind that this calculation is not exact because human body and biochemistry is not a strict science like a math. We do not know all the variables and how they affect the body but the point is that Silymarin estrogenic effects are not just a placebo – they are very real.
The symptoms of estrogenicity of Milk Thistle
Breast tenderness, weird feeling in breasts, puffy nipples, tingling or itchiness in the nipple or underarm area and even lactation.
You still think that Silymarin (Milk thistle extract) is the best option for your liver?
Maybe, and maybe not!
It is up to you to decide, the science and anecdotal experiences speak for themselves.
We have the other options like NAC, Artichoke, Alpha Lipoic Acid and many more supplements which may not have so strong estrogenic “side-effects” and may still help us to protect our livers.
Also if you can get your doctor to prescribe you the Ursodeoxycholic acid (UCDA) it might be very useful. This bile acid is probably the most gentle on the liver and it is usually prescribed for certain liver diseases and cholesterol gallstones.
You can read more about the Ursodeoxycholic acid in my previous post “Bile acids toxicity, endotoxins and leaky gut”.
Just keep in mind that most (if not all) plants have some amounts of estrogenic compounds in them. Even the wheat which you might not know about. It is really not just soy which is well known for this fact. The difference is a concentration and potency of those phytoestrogens.
So, any supplement (mostly herbal extracts) may have some negative effects on your body and hormonal system due to its estrogenicity.
Conclusion
“Its not the customers job to know what they want…”
– Steve Jobs
Sure, the customers want something they get to know, then they buy something and use something.
And it is not the producers job to tell the customers about all the effects you may experience by using their product.
Not just the producers are not aware of all the effects of their products but they may not want you to know about the all effects.
Just like you won’t read about the detrimental health effects of sweet carbonated drinks on the bottles.
Tooth enamel erosion, tooth decay, irritability, aggressiveness, insomnia, anxiety, fatty liver, weight gain, hormonal imbalances,… are just some of the effects of those “delicious” drinks you may buy in a grocery store.
And the energy drinks are even worse due to the caffeine content.
And you can buy as many cans or bottles of those carbonated drinks full of high-fructose corn syrup whether you are 5 years old, 18 years old or 100 years old.
Governments do not protect us.
If they did, they would make the producers of everything including the food state the major possible (side) effects of any particular product on the labels.
Today, they only ban the products (which otherwise might be very helpful as health tonics) or even make them illegal which is not a freedom.
References:
1) Forinash AB, Yancey AM, Barnes KN, Myles TD. The use of galactogogues in the breastfeeding mother. Ann Pharmacother. 2012 Oct;46(10):1392-404.
2) Capasso R, Aviello G, Capasso F, Savino F, Izzo AA, Lembo F, Borrelli F. Silymarin BIO-C, an extract from Silybum marianum fruits, induces hyperprolactinemia in intact female rats. Phytomedicine. 2009 Sep;16(9):839-44.
3) Di Pierro F, Callegari A, Carotenuto D, Tapia MM. Clinical efficacy, safety and tolerability of BIO-C (micronized Silymarin) as a galactagogue. Acta Biomed. 2008 Dec;79(3):205-10.
4) Vojtísek B, Hronová B, Hamrík J, Janková B. Milk thistle (Silybum marianum, L., Gaertn.) in the feed of ketotic cows. Vet Med (Praha). 1991 Jun;36(6):321-30.
5) Lin TH, Yeh S, Chang C. Tissue-specific knockout of androgen receptor in mice. Methods Mol Biol. 2011;776:275-93.
6) A J Notini, R A Davey, J F McManus, K L Bate and J D Zajac. Genomic actions of the androgen receptor are required for normal male sexual differentiation in a mouse model. J Mol Endocrinol. 2005 Dec;35(3):547-55.
7) Zhu W, Zhang JS, Young CY. Silymarin inhibits function of the androgen receptor by reducing nuclear localization of the receptor in the human prostate cancer cell line LNCaP. Carcinogenesis. 2001 Sep;22(9):1399-403.
8) Kummer V, Mašková J, Čanderle J, Zralý Z, Neča J, Machala M. Estrogenic effects of silymarin in ovariectomized rats. Vet. Med-Czech 46, 2001 (1): 17-23
9) Masanori Yamamoto, Hatsuki Hibi, Satoshi Katsuno, Koji Miyake. SERUM ESTRADIOL LEVELS IN NORMAL MEN AND MEN WITH IDIOPATHIC INFERTILITY. Int J Urol. 1995 Mar;2(1):44-6.
10) Barkhem T, Carlsson B, Nilsson Y, Enmark E, Gustafsson J, Nilsson S. Differential response of estrogen receptor alpha and estrogen receptor beta to partial estrogen agonists/antagonists. Mol Pharmacol. 1998 Jul;54(1):105-12.
11) Seidlová-Wuttke D, Becker T, Christoffel V, Jarry H, Wuttke W. Silymarin is a selective estrogen receptor beta (ERbeta) agonist and has estrogenic effects in the metaphysis of the femur but no or antiestrogenic effects in the uterus of ovariectomized (ovx) rats. J Steroid Biochem Mol Biol. 2003 Aug;86(2):179-88.
12) P. E. Lønning. The potency and clinical efficacy of aromatase inhibitors across the breast cancer continuum. Ann Oncol (2011) 22 (3): 503-514.