I’ve been asked about licorice and hypokalemia. So here’s the short answer. The adrenal cortex make two classes of steroids – glucocorticoids (cortisol) and mineralocorticoids (aldosterone). Steroid hormones initiate their effect by activating an intracellular receptor. I’ll limit my discussion to the effect of aldosterone on the principal cell of the cortical collecting tubule. There aldosterone stimulates the Na-K-ATPase (directly or indirectly). This results in sodium reabsorption and potassium secretion. Excess of aldosterone leads to hypertension (because of the sodium retention) and hypokalemia because of excess potassium secretion and consequent urinary loss. It also causes increased acid excretion and thus metabolic alkalosis via a mechanism I have omitted.
The kidney could distinguish cortisol from aldosterone by having mineralocorticoid specific receptors which it has, but most of the steroid receptors are nonspecific responding to either cortisol or aldosterone. In a failure of Occam’s razor, God decided to deal with this problem using a more complicated scheme. This is not the only time God forsook Occam when designing the kidney – bicarbonate reabsorption is another example.
To ensure that every time you get a surge of cortisol you don’t get a mineralocorticoid response God (you can substitute evolution if it makes you happier) created 11-beta-hydroxysteroid dehydrogenase. This enzyme metabolizes cortisol to cortisone which does not activate the renal steroid receptors preventing an inappropriate mineralocorticoid response.
Licorice contains glycyrrhizic acid which inhibits 11-beta-hydroxysteroid dehydrogenase thus allowing cortisol to exert an aldosterone like effect; ie cortisol is not metabolized to cortisone and thus stimulates sodium retention, potassium wastage, and acid excretion. A licorice glutton presents with high blood pressure and hypokalemic metabolic alkalosis. He looks just like a patient with primary hyperaldosteronism, but when aldosterone levels in the blood are measured they are zero. A history of large consumption of licorice makes the diagnosis.
Only natural licorice has this effect because only it contains glycyrrhizic acid. Most of the licorice sold has artificial flavoring and thus does not convey risk. An interesting example of organic being worse than artificial. How much natural licorice consumption will cause this syndrome is not known, but it’s a lot. So if you like natural licorice and you take it in moderate amounts there’s nothing to worry about.
Since biology operates under the rule that anything that can go wrong will go wrong, patients have been described with a genetic defect in 11-beta-hydroxysteroid dehydrogenase. Thus they present with a syndrome identical to that caused by licorice gluttony only they haven’t taken licorice. With all the perils nature hurls at us, it’s remarkable that life exists on Earth.
Fascinating!! Makes perfect sense as I rarely salt anything and eat lots of fruit (high potassium). I just never had a taste for salt. I was always puzzled about how raw licorice worked. And the glycyrrhizic acid is removed in processing!! I had no idea.
Occam’s razor. I had to look up. Sort of KISS?? Keep it simple stupid???
Thank you so much.
Operafilly
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I actually have the opposite problem to Sylvia in that I crave salt.but since I have naturally high cortisol levels and naturally low aldosterone I wonder if taking the licorice is working for me. if my body is ignoring the extra cortisol it naturally produces (according to testing) the perhaps the licorice does help me. It certainly seems to. I take potassium supplements just in case.
Hiya this is precisely why licorice is so useful for POTS (Postural Orthostatic Tachycardia Syndrome) sufferers. I am so glad I love the stuff. Dutch double salted, Swedish, Finnish… Yyummm!
My mother is a kidney patient, having hyperkalemia. Is licorice appropriate for her?
Best to have your mother see her doctor for treatment of her hyperkalemia. The appropriate treatment depends on its cause. Licorice is not used for this purpose. Its dose response curve is not known.
There is an interesting article that appeared couple of months after this post in 2009 at K.I. Swiss researchers administered about 500 mg of licorice (obtained from China as a powder) to 20 hemodialysis patients twice a day through cookies, and got interesting results: A reduced frequency of severe hyperkalemia (which they defined as > 6 mmol/L) when compared to placebo was observed; and within days, it produced a sustained decline of potassium prior to dialysis, prompting higher dialysate K concentrations, they measured the ratio of plasma cortisol/cortisone and as expected it was noted to be elevated as well as a reduction of also/renin ratio. The treatment seemed to be well tolerated, no differences in BP (most likely due to the dialysis on BP) or interdialytic weight gain.
Here is the reference, is free: http://kidney-international.theisn.org/article/S0085-2538(15)54066-0/pdf
Can eating too much licorice as a child cause a countersymptomatic disorder (my invented word) as an adult – high pottassium levels, low sodium and chloride and metabolic acidosis, together with low blood pressure – and susceptible to anxiety due to the metabolic acidosis?
What you describe sounds like aldosterone deficiency or resistance. I doubt there’s any connection to licorice ingestion. Best to see a physician expert in metabolic disorders of this type.
Hello – this was interesting. I’m a singer with asthma 9 dammit) and take LABA medicines which impact potassium levels. I also love herbal teas with licorice in them. Any advice?
Licorice in moderate doses causes no harm. You have take a very large amount of the stuff for it to cause hypokalemia.
Is herbal licorice root supplement dangerous? I’ve been prescribed this by my naturopath for POTS. A lot of potsies have good results. I’m a little nervous though…
The full dose is 800mg
It’s best not to self medicate if you have POTS. There’s more than one type and the therapy should be individualized. See a doctor expert in the syndrome.
Many thanks. 🙂
Just spent a night in hospital with low K and a transient dysrhythmia and metabolic alkalosis from a love of black licorice. Sadly, I have to vote black licorice off the island. Thanks for a well written piece!
I started using Licorice for it benefits 1month ago, now I have this kalium ++6.70 mmol/L in bloodlabo. Thanks for the info.