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Jaseok

Traditionally used for: Traditional use only — no proven use. Trouble sleeping; Ringing in the ears; Palpitations (a pounding heartbeat).

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What is Jaseok? Jaseok is the Korean name for magnetite, a heavy black iron ore. Its Latin drug name is Magnetitum. Its formula is Fe3O4, and it is also known as lodestone (magnetite). In Korean medicine it is a mineral drug, not a plant. Healers ground the rock to powder and cooked it in water. It was given to calm a restless mind, to help sleep, and to ease ringing in the ears. Here is the short verdict. No human trials back any of these uses. A long record of use is not proof that a remedy works. How does Jaseok work? No one has shown how Jaseok acts in the body. Old texts call it heavy, and say it weighs down a restless mind. That is a traditional idea, not a tested one. Magnetite barely dissolves in water. Most of the powder passes through the gut and leaves in the stool. A small amount of iron may dissolve in stomach acid. The pull of a magnet is not thought to do anything inside you. Any real effect would come from the iron, not from magnetism. That has not been tested in people. What forms does Jaseok come in? Jaseok is sold as a crushed or powdered mineral. Two forms are used: raw Jaseok, and calcined Jaseok, which is burned and then quenched in vinegar. The calcined form is softer and easier to grind. You will most often meet it inside a mixed formula. In a water decoction (a drink made by boiling), it is boiled first for 20 to 30 minutes before the herbs go in. Pills and powders use the fine calcined powder. Where it comes from: Lodestone has been used as a drug for about 2,000 years . It appears in the old Chinese classic Shennong Bencao Jing. From there it passed into Korean practice. In Korea it is listed in the Donguibogam, written by Heo Jun in 1613. It sits in the group of mineral drugs used to settle the mind. Japanese Kampo and Indian tradition used lodestone too.

Helps

What does Jaseok help with? Trouble sleeping (insomnia): This is the best known use. Korean and Chinese texts pair Jaseok with other calming drugs for a restless night. No published human trial has tested Jaseok for sleep. Ringing in the ears (tinnitus): Old books link the ears to the kidney system, and Jaseok to that system. It was mixed into pills for ear noise. There is no trial evidence that it helps. Poor hearing: Classic formulas such as Ercong Wan ("ear-clearing pill") include it for fading hearing. This is tradition only. Hearing loss needs a proper check by a doctor. A pounding or racing heartbeat (palpitations): Texts describe it as anchoring a mind that feels stirred up. It was used for fright and a thumping chest. No human study supports this, and a new pounding heart needs medical care. Dizziness and blurred vision: It was given when dizziness came with headache or red eyes. Modern research has not tested it for this. Sudden dizziness or vision change is a reason to see a doctor, not to self-treat. Wheezing and short breath: Some formulas add it to help the breath settle downward. This use is much less common. There is no trial evidence, and asthma needs proven treatment.

Jaseok

Quick Facts

  • What it is: Jaseok is powdered magnetite (Fe3O4), a mineral drug used in Korean medicine to settle the mind.
  • Main uses: Trouble sleeping, Ringing in the ears, Palpitations (a pounding heartbeat)
  • Best for: Traditional use only — no proven use
  • Active ingredients: Iron oxide (Fe3O4), Trace manganese and silica, Possible lead, arsenic or cadmium as impurities
  • Forms: Raw crushed mineral, Calcined (burned and vinegar-dipped) powder, Pills, Part of mixed water decoctions
  • Time to effect: Unknown — no study has measured it.
  • Side effects: Mostly stomach upset and constipation; iron and heavy metal build-up with long use.
  • Pregnancy & breastfeeding: Avoid in pregnancy and while breastfeeding.

Educational information, not medical advice — ask your doctor or midwife.

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What is Jaseok?

Jaseok is the Korean name for magnetite, a heavy black iron ore. Its Latin drug name is Magnetitum. Its formula is Fe3O4, and it is also known as lodestone (magnetite).

In Korean medicine it is a mineral drug, not a plant. Healers ground the rock to powder and cooked it in water. It was given to calm a restless mind, to help sleep, and to ease ringing in the ears.

Here is the short verdict. No human trials back any of these uses. A long record of use is not proof that a remedy works.

How does Jaseok work?

No one has shown how Jaseok acts in the body. Old texts call it heavy, and say it weighs down a restless mind. That is a traditional idea, not a tested one.

Magnetite barely dissolves in water. Most of the powder passes through the gut and leaves in the stool. A small amount of iron may dissolve in stomach acid.

The pull of a magnet is not thought to do anything inside you. Any real effect would come from the iron, not from magnetism. That has not been tested in people.

What forms does Jaseok come in?

Jaseok is sold as a crushed or powdered mineral. Two forms are used: raw Jaseok, and calcined Jaseok, which is burned and then quenched in vinegar. The calcined form is softer and easier to grind.

You will most often meet it inside a mixed formula. In a water decoction (a drink made by boiling), it is boiled first for 20 to 30 minutes before the herbs go in. Pills and powders use the fine calcined powder.

Where it comes from:

Lodestone has been used as a drug for about 2,000 years. It appears in the old Chinese classic Shennong Bencao Jing. From there it passed into Korean practice.

In Korea it is listed in the Donguibogam, written by Heo Jun in 1613. It sits in the group of mineral drugs used to settle the mind. Japanese Kampo and Indian tradition used lodestone too.

Who should avoid Jaseok?

  • Do not use if you are pregnant, breastfeeding, or trying to get pregnant.
  • Do not use if you are thinking of giving it to a child or a teenager.
  • Do not use if you have haemochromatosis (a disease that stores too much iron) or any other iron overload problem.
  • Do not use if you already take an iron tablet or an iron-containing multivitamin.
  • Do not use if you have kidney disease or liver disease.
  • Do not use if you have a peptic ulcer (a sore in the stomach lining), an inflamed bowel, or long-term constipation.
  • Do not use if you take a thyroid pill, a tetracycline or quinolone antibiotic, a Parkinson's drug, a bone drug such as alendronate, or penicillamine, unless your doctor has approved it and set the timing.
  • Do not use if the product has not been tested for lead, arsenic and cadmium.
  • Do not use if you have anaemia (low blood count) that has not been checked by a doctor, because the cause matters more than the mineral.

When should you see a doctor?

See a doctor right away if you have black or tarry stools, blood in your vomit, bad belly pain, or you stop passing stool. Get medical help the same day for a fast or pounding heartbeat, chest pain, fainting, or new trouble breathing. Book a check-up if ringing in the ears, hearing loss, or dizziness is new, is getting worse, or affects one ear only. Also see a doctor if sleep problems last more than a few weeks, or if you feel very tired, weak or joint-sore after taking mineral products for a long time.

Evidence grades and traditional-use labels are explained in our methodology. Nothing here is medical advice.

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