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Q: Differing forms of Magnesium supplements. ( Answered 5 out of 5 stars,   0 Comments )
Subject: Differing forms of Magnesium supplements.
Category: Health > Fitness and Nutrition
Asked by: chrisstu-ga
List Price: $25.00
Posted: 19 Oct 2004 06:24 PDT
Expires: 18 Nov 2004 05:24 PST
Question ID: 416926
Magnesium supplementation is often recommended for disorders of sleep,
muscle, or bone,ect. The supplements however differ and may contain
Mag Oxide, Mag glycinate, Mag citrate/malate, or Mag aspartate. What
are the various types of magnesium used for and at what typical
dosages? Any warnings associated with the different forms?
Subject: Re: Differing forms of Magnesium supplements.
Answered By: crabcakes-ga on 19 Oct 2004 11:37 PDT
Rated:5 out of 5 stars
Hello  chrisstu,

 Magnesium is a cation that acts as a muscle relaxant, and it also has
 anti-inflammatory properties.It is an important element for bones,
teeth, muscles, soft tissue, kidenys and cardiac function. Magnesium
is also imortant in carbohydrate and protein digestion and synthesis.

 It is hard to determine which form of magnesium is *THE* most readily
absorbed if you read any web sites that sell this supplement, as each
site purports it's own compound is best! I have located information
from reliable web sites for you,  and the conclusion is that magnesium
citrate is a winner! Keep in mind that absorption of most forms can
vary person to person, depending on age and health. Buying a magnesium
citrate form or the magnesium L-lactate dihydrate form would give you
greater bioavailability. If you are in good health, you will probably
benefit from most forms recommended in this answer, even the ones with
lesser absorptive properties. Reliable studies on magnesium absorption
are not available, due to the variance between subjects, and lack of
accurate testing methods. Fecal and urine elimination of magensium are
hard to measure due to the very short half-life of the magnesium

"Magnesium is a naturally occurring mineral. Magnesium is important
for many systems in the body especially the muscles and nerves.
Magnesium citrate also increases water in the intestines, which may
induce defecation.
Magnesium hydroxide is used as a laxative to relieve occasional
constipation (irregularity)."

Yale New Haven Health recommends a dose of 400mg per day." Magnesium.
This mineral helps strengthen muscles and improve certain body
functions. However, magnesium supplements have such side effects as
abdominal pain, irregular heartbeat, diarrhea, and appetite
loss?especially in those older than 55. Recommended daily intake: 400

Whole Health MD agrees:
"Suggested dose:400 mg magnesium and 100 mg calcium twice a day. Take
with food for best absorption. People with kidney disease should check
with their doctor before taking magnesium.",1513,21,00.html

"Magnesium deficiency is rare, but when it occurs it is often caused
by conditions that interfere with the ability of the intestines to
absorb magnesium from food, by poor diet, or by losing magnesium from
prolonged vomiting or diarrhea. People who have diabetes and those who
drink excessive amounts of alcohol, overuse diuretics, or have burns
over a large area of their bodies are at high risk for developing a
magnesium deficiency. Symptoms of a magnesium deficiency include
weakness, dizziness, irregular heartbeat, tremors, and seizures.

An increased amount of magnesium in the blood can be caused by kidney
failure or by excessive use of certain medications that contain
magnesium (such as antacids or laxatives). Occasionally, an increased
blood level of magnesium can be caused by problems with the thyroid or
parathyroid glands Click here to see an illustration. (such as
hypothyroidism or hyperparathyroidism)."

"Magnesium citrate was significantly more soluble than magnesium oxide
in all levels of acid secretion, but reprecipitation from magnesium
oxide and magnesium citrate did not occur when the hydrochloric acid
was titrated to a pH between 6 and 7, which is the pH of the distal
small intestine where magnesium anions are absorbed. Absorption of the
two magnesium formulations was also compared in vivo by measuring the
rise in urinary magnesium levels, and the citrate form was absorbed to
a much greater extent than the oxide."

"Absorption and bioavailability of preparations vary, as do
concomitant side effects. Various investigators have reported that
magnesium L-lactate dihydrate, which is available in a
sustained-release formulation, ensures maximal absorption in the
distal small intestine. The solubility and bioavailability of
magnesium L-lactate dihydrate are higher than those of other magnesium
formulations, and the low incidence of side effects and a bid dosing
schedule may provide the additional benefit of patient compliance."

Dosage froms of magnesium:

    * Oral Magnesium Chloride
          o Tablets (U.S.)
          o Enteric-coated tablets (U.S.)
          o Extended-release tablets (U.S.)
    * Magnesium Citrate
          o Oral solution (U.S. and Canada)
    * Magnesium Gluceptate
          o Oral solution (Canada)
    * Magnesium Gluconate
          o Oral solution (U.S.)
          o Tablets (U.S. and Canada)
    * Magnesium Hydroxide
          o Tablets (U.S.)
          o Chewable tablets (U.S. and Canada)
          o Oral solution (U.S. and Canada)
    * Magnesium Lactate
          o Extended-release tablets (U.S.)
    * Magnesium Oxide
          o Capsules (U.S.)
          o Tablets (U.S. and Canada)
    * Magnesium Pidolate
          o Powder for oral solution (Canada)
    * Magnesium Sulfate
          o Crystals (U.S.)

    * Magnesium Chloride
          o Injection (U.S.)
    * Magnesium Sulfate
          o Injection (U.S. and Canada)

The above site also states the following warnngs:
Although certain medicines or other dietary supplements should not be
used together at all, in other cases they may be used together even if
an interaction might occur. In these cases, your health care
professional may want to change the dose, or other precautions may be
necessary. When you are taking magnesium, it is especially important
that your health care professional know if you are taking any of the

    * Cellulose sodium phosphate?Use with magnesium supplements may
prevent cellulose sodium phosphate from working properly; magnesium
supplements should be taken at least 1 hour before or after cellulose
sodium phosphate

    * Magnesium-containing preparations, other, including magnesium
enemas?Use with magnesium supplements may cause high blood levels of
magnesium, which may increase the chance of side effects

    * Sodium polystyrene sulfonate?Use with magnesium supplements may
cause the magnesium supplement to be less effective

    * Tetracyclines, oral?Use with magnesium supplements may prevent
the tetracycline from working properly; magnesium supplements should
be taken at least 1 to 3 hours before or after oral tetracycline

Other medical problems?The presence of other medical problems may
affect the use of magnesium. Make sure you tell your health care
professional if you have any other medical problems, especially:

    * Heart disease?Magnesium supplements may make this condition worse

    * Kidney problems?Magnesium supplements may increase the risk of
hypermagnesemia (too much magnesium in the blood), which could cause
serious side effects; your health care professional may need to change
your dose

The follwing forms of magnesium are all acceptable dietary forms,
according to the Canadian Therapeutic Products Directrate:

magnesium HVP/HAP chelate

It seems that magnesium aspartate or magnesium citrate are some of the
most absorbable forms,with magnesium bicarbonate, magnesium oxide and
magnesium carbonate being the least readily absorbed forms.
Additionally, magnesium is better absorbed, in any form, when taken
with food.

"Some calcium-magnesium combinations are formulated with hydrochloric
acid and vitamin D to aid mineral absorption. Taking them before
bedtime may be very helpful in increasing utilization of both these
important minerals and lead to better sleep."

"Magnesium chelated with amino acids is probably the most absorbable
form. Less absorbable forms include magnesium bicarbonate, magnesium
oxide, and magnesium carbonate. Magnesium oxide is probably somewhat
better than magnesium carbonate (dolomite). The newly available salts
of magnesium aspartate or citrate, both known as mineral transporters,
have a better percentage absorption."

"Who should not take magnesium oxide?
	? Do not take magnesium oxide without first talking to your doctor if
you have kidney disease.
	? Before taking magnesium oxide, tell your doctor if you have any
other medical conditions, allergies, or if you take other medicines or
other herbal/health supplements. Magnesium oxide may not be
recommended in some situations.
	? It is not known whether magnesium oxide will harm an unborn baby.
Do not take magnesium oxide without first talking to your doctor if
you are pregnant or planning a pregnancy.
	? It is not known whether magnesium oxide will harm an nursing baby.
Do not take magnesium oxide without first talking to your doctor if
you are breast-feeding a baby.

What are the possible side effects of magnesium oxide?
	? Stop taking magnesium oxide and seek emergency medical attention if
you experience an allergic reaction (difficulty breathing; closing of
your throat; swelling of your lips, tongue, or face; or hives).
	? Other, less serious side effects may be more likely to occur.
Continue to take magnesium oxide and talk to your doctor if you
experience diarrhea or an upset stomach.
	? Side effects other than those listed here may also occur. Talk to
your doctor about any side effect that seems unusual or that is
especially bothersome.

WARNING! Magnesium can be toxic for those who have either renal
(kidney/liver) problems or atrioventricular blocks.

Magnesium supplements and antacids that contain magnesium can
interfere with the absorbtion of the antibiotic azithromycin.

One study found a newer formulation of potassium-magnesium-citrate
(K4MgCit2) had fewer side effects and was better tolerated.

The chloride form of magnesum, MgCl2, is found in adundance in the ocean.

"Magnesium supplements can be taken as oral tablets, liquid, or as
intramuscular injections. Oral magnesium is easy to take, but tends to
be poorly absorbed. Magnesium chloride, citrate, gluconate and sulfate
are the forms that the body absorbs best, while Magnesium oxide is
often the cheapest, but is also the most poorly absorbed. Magnesium
sulfate injections can be painful are are certainly more time
consuming than simply taking an oral dose at home, but the injections
seem to be a more reliable method of producing symptom improvement,
even if the individual has a normal red cell magnesium count."

"The magnesium hydroxide is widely used for the treatment of peptic
ulcers and gastric hyperacidity. The MgO can be used as source of
magnesium in certain pharmaceutical products. Magnesium oxide is used
as a source of magnesium in the manufacture of pharmaceutical
magnesium stearates

Magnesium  carbonate can be used as a base in the treatment of
dyspepsia, rhumatism and gout"

More information about magnesium can be found on this National
Institutes of Health site:

Magnesium Compounds

Discovery Health

I hope this has helped you select a useful magnesium compound. If any
part of this answer is unclear, please utilize the Answer
Clarification  button before rating, and I will be happy to assist you


Search Terms
magnesium absorption studies
magnesium compounds absorbable
magnesium compounds + supplements -buy -pharmacy

Request for Answer Clarification by chrisstu-ga on 19 Oct 2004 12:30 PDT
WOW. Excellent Job!!! Very much appreciated. Can I request you in the future?

Clarification of Answer by crabcakes-ga on 19 Oct 2004 12:39 PDT
Thank you for the 5 stars and the nice tip! I'm glad you were pleased
with the answer! Anytime you would like to request a certain
researcher, simply add the person's name in the "Subject" line.

chrisstu-ga rated this answer:5 out of 5 stars and gave an additional tip of: $5.00

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