pieces of black licorice candy

Licorice has been around for thousands of years. The plant (Glycyrrhiza glabra) from which it is derived was found in the tombs of Egyptian pharaohs and was treasured by healers in the ancient Middle East. The father of modern medicine, Hippocrates, considered licorice root a valuable healing herb.

Although modern day herbalists still use licorice for digestive upset, coughs and arthritis, most people think of it as flavoring for candy. Many confectioners use less expensive artificial flavors or anise, but true aficionados demand the real thing. High-quality licorice, often from Europe, contains the active ingredient glycyrrhizin.

There is a dark side to licorice, though. When candy containing real licorice extract is consumed regularly or in large quantities, there can be profound metabolic consequences.

Fluid and sodium are retained, blood pressure goes up and potassium may drop to dangerously low levels. Hormonal changes can occur and may lead to weakness and in extreme cases temporary paralysis.

We were impressed years ago with the story of a 22-year-old Swedish gym teacher. She had been healthy, but then developed horrific headaches every month and lost her periods. She also had frighteningly high blood pressure, around 240/130. Against all of that, her primary complaint of loss of libido must have seemed insignificant.

It turned out that she had been gobbling down large quantities of licorice. Once she stopped, all of her symptoms gradually disappeared.

One reader recently reported her own experience, which did not involve bingeing on candy:

“A week ago at the direction of a health care professional I took a prescribed antifungal to treat Candida. I saw the ‘Licorice Root’ listed on the label and remembered hearing many years ago that licorice could raise blood pressure, but I figured a health care professional would take that into consideration. By midday, though, I was hit with a bad headache and when I took my BP it was 180/100. That scared the heck out of me. Since then it’s been as high as 190/102, which scares me even more.

“My regular doctor had just reduced the dose of my BP med because I had lost weight and my reading had been 120/68. Trying to combat this sudden spike in pressure and the unrelenting headaches, I increased the dose of my blood pressure medicine again, but it did not help. How long does it take for the effects of licorice to leave the body? I have not taken any for a week, but my pressure is still higher than it should be.”

Based on the report of the Swedish gymnastics teacher, blood pressure should return to normal within two weeks.

Some natural remedies contain licorice root. Just as with candy, this can pose a risk for susceptible people.

One form of licorice is substantially safer. DGL (deglycyrrhizinated licorice) has most of the glycyrrhizin removed. This makes it less likely to raise blood pressure or cause hormone disruption. DGL is often used to treat heartburn, ulcers, canker sores and other digestive distress.

When it comes to licorice, whether it is candy or medicine, moderation is advisable. Before taking anything containing glycyrrhizin or licorice root, ask about the potential for side effects and what to do if they occur.

If you have had side effects from licorice, you can share them in the comments below.

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  1. DB

    A lot of herbal tea blends have licorice root as one of the ingredients. Is this the same thing as the black licorice?

  2. John M.

    When I was younger, I had a bad experience with black licorice. I ate some about an hour before I went to bed. The next thing I knew, I was on the couch with at doctor hanging over me saying, “I think he will be all right!” My mother was in tears. She had heard me making strange sounds in the night and came in to check. If she had not heard me, who knows what might have happened. Since that day, not one drop of licorice has passed my lips, no matter what the color is.

  3. Kahleen

    Beware everyone – I took the DGL supplement for a month and my blood pressure skyrocketed! So even a small amount of licorice in anything can have a bad affect on anyone who could be (& may not even now it) sensitive. This was distributed by a very good company in Canada.
    I bought it in the organic section of my grocery store. I told the employee about what happened to me and she was very glad to get the feedback so she could warn others. I started taking this after I heard it was recommended on the Dr. Oz Show. Be careful because everything he recommends needs to be tested out per person also.

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