How to Lower SHBG (Sex Hormone Binding Globulin)

I receive a lot of questions regarding how to reduce SHBG levels. Is it possible to reduce SHBG levels naturally or by supplements? In this post, I try to address this issue.

What is SHBG (Sex hormone binding globulin) and why it matters?

Sex hormone binding globulin (SHBG) is a glycoprotein produced by the liver. Accordance with its name, SHBG circulates in the blood “binding” hormones flowing out there and suppressing them useless.

However, SHBG binds and suppresses estrogen (estradiol) about ten times less effective than it binds androgen. In other words, high levels of SHBG is not a good thing to testosterone. Repeatedly measured high SHBG is usually bad news for a man because it can mean that you might have serious health problems.

The general normal SHBG reference range for males is ~20-60 nmol/L

High-value SHBG 71-120 nmol/l might be caused by the following:
– Liver disease: cirrhosis and fatty liver may increase SHBG levels.
– Too much estradiol in the body.
– Hyperthyroidism.1Ford HC, Cooke RR, Keightley EA, Feek CM. Serum levels of free and bound testosterone in hyperthyroidism. Clin Endocrinol (Oxf). 1992 Feb;36(2):187-92. doi: 10.1111/j.1365-2265.1992.tb00956.x. PMID: 1568351.
– Vitamin D, magnesium and zinc deficiency.
– HIV infection.

At first glance, low SHBG might sound good, because it also means that biologically active free testosterone levels are also high. However, the concern here is that low levels of SHBG might be linked to heart disease and insulin resistance in men.

Low-value SHBG 0-16 nmol/l:
– High biologically active free testosterone levels.
– Risk of insulin resistance.2Katsuki A, Sumida Y, Murashima S, Fujii M, Ito K, Tsuchihashi K, Murata K, Yano Y, Shima T. Acute and chronic regulation of serum sex hormone-binding globulin levels by plasma insulin concentrations in male noninsulin-dependent diabetes mellitus patients. J Clin Endocrinol Metab. 1996 Jul;81(7):2515-9. doi: 10.1210/jcem.81.7.8675570. PMID: 8675570.
– Increased risk of death from cardiovascular disease.3Kalme T, Seppälä M, Qiao Q, Koistinen R, Nissinen A, Harrela M, Loukovaara M, Leinonen P, Tuomilehto J. Sex hormone-binding globulin and insulin-like growth factor-binding protein-1 as indicators of metabolic syndrome, cardiovascular risk, and mortality in elderly men. J Clin Endocrinol Metab. 2005 Mar;90(3):1550-6. doi: 10.1210/jc.2004-0762. Epub 2004 Dec 21. PMID: 15613437.

High SBHG levels might lower testosterone

Common things that might affect SHBG levels

  • Too small protein intake might increase your SHBG levels, according to older study.4Anderson KE, Rosner W, Khan MS, New MI, Pang SY, Wissel PS, Kappas A. Diet-hormone interactions: protein/carbohydrate ratio alters reciprocally the plasma levels of testosterone and cortisol and their respective binding globulins in man. Life Sci. 1987 May 4;40(18):1761-8. doi: 10.1016/0024-3205(87)90086-5. PMID: 3573976. Try upping your protein intake to 1,5-2 grams per body weight.
  • Too much alcohol. If you are drinking enough alcohol to ruin your liver it will increase your SHBG levels.5Iturriaga H, Lioi X, Valladares L. Sex hormone-binding globulin in non-cirrhotic alcoholic patients during early withdrawal and after longer abstinence. Alcohol Alcohol. 1999 Nov-Dec;34(6):903-9. doi: 10.1093/alcalc/34.6.903. PMID: 10659727.

    Iturriaga H, Valladares L, Hirsch S, Devoto E, P’erez C, Bunout D, Lioi X, Petermann M. Effects of abstinence on sex hormone profile in alcoholic patients without liver failure. J Endocrinol Invest. 1995 Sep;18(8):638-44. doi: 10.1007/BF03349782. PMID: 8655923.
    To drink alcohol more safely check out -> Hangover cures (how to drink without ruining your health)
  • Too much-caffeinated drinks (+6 cups of coffee, green tea or caffeinated drink) might increase SHBG levels if you believe studies made on pre/postmenopausal women.6Kotsopoulos J, Eliassen AH, Missmer SA, Hankinson SE, Tworoger SS. Relationship between caffeine intake and plasma sex hormone concentrations in premenopausal and postmenopausal women. Cancer. 2009 Jun 15;115(12):2765-74. doi: 10.1002/cncr.24328. PMID: 19384973; PMCID: PMC2764240.

    Nagata C, Kabuto M, Shimizu H. Association of coffee, green tea, and caffeine intakes with serum concentrations of estradiol and sex hormone-binding globulin in premenopausal Japanese women. Nutr Cancer. 1998;30(1):21-4. doi: 10.1080/01635589809514635. PMID: 9507508.
    4-5 cups of coffee is the sweet spot for reaping coffee’s health benefits, so no reason to go overboard.
  • High estrogen. If you have high estrogenic hormones your body will increase SHBG production.7Pugeat M, Nader N, Hogeveen K, Raverot G, Déchaud H, Grenot C. Sex hormone-binding globulin gene expression in the liver: drugs and the metabolic syndrome. Mol Cell Endocrinol. 2010 Mar 5;316(1):53-9. doi: 10.1016/j.mce.2009.09.020. Epub 2009 Sep 26. PMID: 19786070.

Is it possible to lower SHBG levels naturally?
It can be challenging, as there are not really many effective supplements or strategies to lower it (clear science-based evidence). In this article, I will list those nutritional strategies and supplements which have at least some kind evidence on lowering SHBG levels. This information is meant to be educational, not medical advice. Always consult your doctor first if your shbg levels are out of the normal range.

Supplements to lower SHBG

Next, I will list nutritional strategies and supplements which have been linked and studied on lowering sex hormone binding globulin levels in humans.

Vitamin D

vitamin-d-shbg-levels
Vitamin D shbg levels

Numerous studies have shown that low vitamin D levels is will keep your testosterone levels low. But did you know that low vitamin D levels can also alter your SHBG levels.8Nimptsch K, Platz EA, Willett WC, Giovannucci E. Association between plasma 25-OH vitamin D and testosterone levels in men. Clin Endocrinol (Oxf). 2012 Jul;77(1):106-12. doi: 10.1111/j.1365-2265.2012.04332.x. PMID: 22220644.

Pilz S, Frisch S, Koertke H, Kuhn J, Dreier J, Obermayer-Pietsch B, Wehr E, Zittermann A. Effect of vitamin D supplementation on testosterone levels in men. Horm Metab Res. 2011 Mar;43(3):223-5. doi: 10.1055/s-0030-1269854. Epub 2010 Dec 10. PMID: 21154195.

Medical University in Austria found that men with more than 30 microg/l of vitamin D in their bloodstream had significantly lower levels of SHBG and higher levels of testosterone, than those lower than 30 microg/l.9Wehr E, Pilz S, Boehm BO, März W, Obermayer-Pietsch B. Association of vitamin D status with serum androgen levels in men. Clin Endocrinol (Oxf). 2010 Aug;73(2):243-8. doi: 10.1111/j.1365-2265.2009.03777.x. Epub 2009 Dec 29. PMID: 20050857.

Fixing Vitamin D deficiency should be every man’s (and women’s) top priority.

First I recommend taking the blood test (25(OH)D) to see your vitamin D levels. The blood level of vitamin D should be more than 70 nmol/l (optimal level is closer to 110 nmol/l, according to a studies.10Grant WB. An estimate of the global reduction in mortality rates through doubling vitamin D levels. Eur J Clin Nutr. 2011 Sep;65(9):1016-26. doi: 10.1038/ejcn.2011.68. Epub 2011 Jul 6. PMID: 21731036.

A good rule of thumb for taking vitamin D supplementation, according to Vitamin D council: Take 1000 IU (25 mg) per 10 pounds of your body weight. For example, if you weight 110 lbs (50kg) is worth of taking 5,000 IU (125mg) per day.11Vitamin D Council was a nonprofit organization dedicated to promoting the use of vitamin D for optimal health

A safe upper limit for adults is 10,000 IU / day.
It’s not worth to take more even if you weight more than 100 pounds (unless you know you have deficiency by a blood test). After 1-2 months of supplementing vitamin D check your blood levels again and adjust supplement dosage from there.

Take Vitamin D with your meals?
Vitamin D should be taken with your fattiest meal, so it is better absorbed (Vitamin D is fat-soluble vitamin).

Fortunately fixing vitamin D levels is one the easiest and cheapest problems to fix. Just take 10-20 minutes sun almost every day or take vitamin D supplements.

How to choose vitamin D supplements?
When choosing vitamin D supplements, make sure you get cholecalciferol (vitamin D3) form, which is way more potent than D2 (study). It’s also wise to choose supplements where vitamin D is stored with some kind oil, as vitamin D is fat soluble vitamin (olive oil or MCT-oil).

Price of good quality D vitamin supplements starts at 3 cents per day (from iHerb). But my personal favorite vitamin D supplements is Thorne’s liquid vitamin D + k2 combo.

K2 is an important vitamin converted from vitamin K, but only if you eat enough dark green vegetables.12Thijssen HH, Vervoort LM, Schurgers LJ, Shearer MJ. Menadione is a metabolite of oral vitamin K. Br J Nutr. 2006 Feb;95(2):260-6. doi: 10.1079/bjn20051630. PMID: 16469140. Most people just won’t eat enough kale and spinach so supplementing K2 is also vitally important.

Links to iHerb: Thorne’s liquid vitamin D + k2 combo / Doctor’s Best Vitamin D

If you have not yet ordered from iHerb.com, you’ll get 10% off from your first order with code: KLJ962.
Everyone else gets 5% off. You get the discount code automatically from my links and while you’ll benefit from this, I also benefit by getting “iHerb credits” that I can use towards my next orders. Thank you for this!

iHerb.com (Founded in 1996) is one the most reputable online supplement stores. iHerb ships to over 150 different countries and carries a great selection of virtually every natural supplement there is. 

Magnesium

magnesium-lower-shbg
Magnesium lowers shbg

Magnesium is one of the most important minerals for human endocrine system testosterone levels. However, fewer people know that magnesium might also have a suppressing effect on SHBG levels.

Research has shown that magnesium binds to SHBG and interrupts its T suppressing effect. Which actually result to improvement in free testosterone levels.

Magnesium binds SHBG in a nonspecific mode, leading to an uncompetitive inhibition with T in binding SHBG and to a subsequent enhancement of Bio-T availability. The binding is accompanied by a magnesium release (or uptake) with a corresponding heat effect around in magnitude 17 kJ/mol”13Maggio M, De Vita F, Lauretani F, Nouvenne A, Meschi T, Ticinesi A, Dominguez LJ, Barbagallo M, Dall’aglio E, Ceda GP. The Interplay between Magnesium and Testosterone in Modulating Physical Function in Men. Int J Endocrinol. 2014;2014:525249. doi: 10.1155/2014/525249. Epub 2014 Mar 3. PMID: 24723948.

Most people think that they get enough magnesium from their diet, but actually, the truth is quite the opposite. It’s estimated that about 46-60% of the U.S. population doesn’t get enough magnesium from their diet.14Wallace TC, McBurney M, Fulgoni VL 3rd. Multivitamin/mineral supplement contribution to micronutrient intakes in the United States, 2007-2010. J Am Coll Nutr. 2014;33(2):94-102. doi: 10.1080/07315724.2013.846806. PMID: 24724766

Magnesium deficiency is also widespread in Europe. It’s almost impossible to get enough magnesium from today’s foods, even if your diet is perfect.

Which magnesium type to use?

Magnesium glycinate – Magnesium mixed with amino acid glycine is one of the best absorbable forms of magnesium. Glycine is one of the most widespread amino acid found in the human body and has certain benefits from calming nerves to promoting better sleep.

Magnesium glycinate is the best choice for those trying to fix their magnesium deficiency, as its less likely to cause laxative effects with high doses. Magnesium glycinate is also a good choice for those who take magnesium for better sleep because sleep promoting and calming effects of glycinate.

I recommend this form only for calming and improving sleep as it’s a quite expensive form (not for general magnesium deficiency). I personally use Metabolic Maintenance magnesium glycinate. (Available on iHerb.)

Magnesium citrate – Magnesium mixed with citric acid in a 1:1 ratio. Magnesium citrate high doses can cause laxative effects, especially if you take it on empty stomach, thus it’s recommended to be taken with meals.

Magnesium citrate has good bioavailability and inexpensive, making it the best value for money for getting more magnesium to your diet.

Personal favorite: Now Foods, Magnesium Citrate. iHerb 100% powder or capsules.

Magnesium oil – Very good for sore muscles and help to recover from hard training. Best results are obtained by rubbing magnesium oil to the skin and leave it on for at least 15min.

I recommend Life Flo Magnesium oil from iHerb

Nettle root (Urtica dioica)

nettle-root
Stinging nettle root

Nettle root is better known by its ability to reduce symptoms associated with benign prostate hyperplasia (BPH increased prostate).

If you are suffering from this problem, just as a pointer, not medical advice. Nettle root has shown to alleviated symptoms and even reduced the size of the prostate without side effects in a well-designed double-blind, placebo-controlled study.15 Safarinejad MR. Urtica dioica for treatment of benign prostatic hyperplasia: a prospective, randomized, double-blind, placebo-controlled, crossover study. J Herb Pharmacother. 2005;5(4):1-11. PMID: 16635963.

Nettle root is also touted to lower shbg levels. Which is at least partially true, as nettle root contains lignans which bind to SHBG, interfering its testosterone and estradiol (E2) hunting.16Schöttner M, Gansser D, Spiteller G. Lignans from the roots of Urtica dioica and their metabolites bind to human sex hormone binding globulin (SHBG). Planta Med. 1997 Dec;63(6):529-32. doi: 10.1055/s-2006-957756. PMID: 9434605.

Gansser D, Spiteller G. Plant constituents interfering with human sex hormone-binding globulin. Evaluation of a test method and its application to Urtica dioica root extracts. Z Naturforsch C J Biosci. 1995 Jan-Feb;50(1-2):98-104. PMID: 7702715.

The problem with this is that nettle root also inhibits an enzyme (5α-reductase)175α-Reductases are enzymes involved in steroid metabolism. – Wikipedia that converts testosterone to DHT-hormone (dihydrotestosterone).18Dihydrotestosterone is an endogenous androgen sex steroid and hormone.- Wikipedia Another problem with nettle root is that how you get these lignans to absorb optimally since these lignans are absorbed mainly in the colon.

Peoples experiences with nettle root are quite different. One gets the best erections of his life, others feel nothing.

Personally, I experienced a small rise in sex drive, but as always it could have been just a placebo effect. However nettle root is a perfectly safe herb, so I see no reason not to try it.

Remember we are talking about nettle root here, not a general stinging nettle leaf supplements. Is the stinging nettle’s root that has these components (lignans that bind to shbg).

There are many different forms of nettle root supplements, from powder to alcohol and capsule extracts.

Personally, I use NOW stinging nettle root extract 2 capsules daily for similar dosages used in most studies. Available in iHerb for U.S. and international customers.

Boron

boron-for-lowering-shbg-levels
Boron shbg levels

Boron is an interesting “space trace mineral” (forms from cosmic ray spallation).19Cosmic rays are highly energetic charged particles from beyond Earth. – Wikipedia At the beginning of the 90th century, boron was popular testosterone booster among bodybuilders.

But after studies demonstrated it to be almost useless, the use of boron supplements ceased almost completely. Now as a result of new studies, boron has become popular “SHBG lowering supplement”.

In an older ninety-century study where healthy men took 10mg of boron for 4 weeks showed about 11% increase in testosterone levels. However, men estradiol also rise shocking 42% which is definitely not a good thing.

“Supplementation with 10 mg B/d for 4 wk resulted in 84% of the supplemented dose being recovered in the urine. Plasma estradiol concentrations increased significantly as a result of supplementation (51.9 +/- 21.4 to 73.9 +/- 22.2 pmol/L; p < 0.004) and there was a trend for plasma testosterone levels to be increased”20Naghii MR, Samman S. The effect of boron supplementation on its urinary excretion and selected cardiovascular risk factors in healthy male subjects. Biol Trace Elem Res. 1997 Mar;56(3):273-86. doi: 10.1007/BF02785299. PMID: 9197924.

Another ninety-century study where male bodybuilders were given 2,5 mg boron supplement (probably too small amount for any effect) daily for 7 weeks noted no significant differences in male hormones between placebo group.

“The findings suggest that 7 weeks of bodybuilding can increase total testosterone, lean body mass, and strength in lesser trained bodybuilders and that boron supplementation had no effect on these measures.”21Ferrando AA, Green NR. The effect of boron supplementation on lean body mass, plasma testosterone levels, and strength in male bodybuilders. Int J Sport Nutr. 1993 Jun;3(2):140-9. doi: 10.1123/ijsn.3.2.140. PMID: 8508192.

Lastly, there is very convincing never study where 10mg boron every day with breakfast for a week lowered SHBG (-4,7%) and estradiol (-39%) while increasing free testosterone levels (+28%) and DHT(+6,7%). Though, this study had a small sample size consisting of only 8 people.

Boron in plasma increased significantly following hours and weekly consumption. Six hours supplementation showed a significant decrease on sex hormone binding globulin (SHBG), high sensitive CRP (hsCRP) and TNF-α level. After one week (in samples taken at 8.00 A.M, only), the mean plasma free testosterone increased and the mean plasma estradiol decreased significantly.22Naghii MR, Mofid M, Asgari AR, Hedayati M, Daneshpour MS. Comparative effects of daily and weekly boron supplementation on plasma steroid hormones and proinflammatory cytokines. J Trace Elem Med Biol. 2011 Jan;25(1):54-8. doi: 10.1016/j.jtemb.2010.10.001. Epub 2010 Dec 3. PMID: 21129941.

Optimal boron dosage for lowering SHBG levels?
According to these studies, dosages close to 10mg of boron daily seems to be the optimum dose for testosterone boost and lowering SHBG levels. While small 2,5mg dose daily did nothing.

Studies show mixed results, but again I don’t see a reason not try it. Boron is cheap and perfectly safe supplement up to 20mg daily for adults.23Dietary Reference Intakes – Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc DOI:https://doi.org/10.1016/S0002-8223(01)00078-5

How to get boron?
There are foods that have boron naturally, but it’s almost impossible to get similar dosages which were used in these studies from food.

But generally speaking, you can get your boron daily recommended intake from food.

Foods high in boron: dried fruits (raisins, prunes, apricots), fruits (avocado, red apple), nuts (almonds, hazelnuts, brazil nuts).

Unless you can’t eat 400-500 grams of raisins or other foods high in boron daily, boron supplement is needed to achieve dosages (10mg day) that affect shbg / testosterone levels.

For the best bioavailability, it’s good to choose a mixed complex of 3 forms of boron (citrate/aspartate/glycinate).

I use: Source Natural’s triple boron. I usually take 3 capsules daily (for a total 9mg boron per day).

Available in iHerb for international customers.

Conclusion

There are some herbs and supplements which have some kind of evidence lowering SHBG levels. However, before taking any supplements. I would first suggest to check up with your doctor if you have some health issues that raise your SHBG levels.

After that, start by focusing on the basics. General ignorance about men’s health can wreck your hormones including SHBG levels. Learn the basics of testosterone and men’s health here.

For erection and sex drive keep your estrogen & prolactin low and learn the best strategies for stronger erection that last long.

Afterward, if you still struggle with high SHBG levels and want to lower it, experiment with strategies and supplements mentioned in this article.

3 Comments on “How to Lower SHBG (Sex Hormone Binding Globulin)”

  1. Good info, my shbg levels were little high, but my doctor said its ok.

    I will try to lower it with this guide and report result back later.

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