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One ingredient and nothing else: magnesium chloride hexahydrate from Dead Sea brine, USP grade, with no fillers or anti-caking agents. Below are the label directions for the daily drink, how to use the same powder in a bath or homemade magnesium oil, sizes, safety and documents.
USP grade The producer certifies the raw material to USP-NF, Ph. Eur. and FCC standards. Third-party tested for heavy metals.
Dead Sea Magnesium chloride from Dead Sea brine, packed in an FDA-registered facility in Madera, California.
About 12% magnesium A single-ingredient powder with about 120 mg of magnesium in every gram.
What’s in it
Composition and specifications, Greenway Biotech Magnesium Chloride USP
Item
Detail
Ingredient
Magnesium chloride hexahydrate (MgCl₂·6H₂O), CAS 7791-18-6. Nothing else is added: no fillers, flow agents or anti-caking agents.
Grade
USP. The producer certifies the raw material to USP-NF, Ph. Eur. and FCC standards; see Documents and help.
Origin and packing
Magnesium chloride from Dead Sea brine, packed in Madera, California, in Greenway’s FDA-registered personal-care warehouse, separate from our fertilizer operations. Registration means the facility is on file with the FDA; it is not FDA approval of the product.
Form
White crystalline powder that dissolves completely in water. It draws moisture from the air, so keep the bag sealed.
Magnesium content
11.96% by weight: magnesium (24.305) divided by magnesium chloride hexahydrate (203.30), or about 120 mg of magnesium per gram of powder.
Testing
Third-party tested for heavy metals.
Labeled use
Dietary supplement, taken as a solution you mix. Also used in the bath and to make magnesium oil for skin.
Net contents
1 lb (454 g), 2 lb (907 g), 4 lb (1.81 kg) and 8 lb (3.63 kg) bags, and a pair of 8 lb bags (16 lb, 7.26 kg).
Per serving, calculated from the label directions
Item
Amount
Standard solution
33 g of powder in 1 liter of water: about 3.95 g of magnesium per liter, or 3.95 mg per mL
Serving
45 mL (3 tablespoons) of the solution, once a day
Powder in one serving
About 1.5 g
Magnesium in one serving
About 178 mg, 42% of the 420 mg Daily Value
The serving figures are calculated from the directions on the bag and the formula weight of magnesium chloride hexahydrate. The Supplement Facts panel on your bag is the reference; if it ever differs from this page, follow the bag and let us know.
Uses and routines
One bag, several routines. The daily drink is the labeled supplement use. The bath and the homemade oil are uses for skin, and nothing said about the drink applies to them.
A daily drink
Mix the standard solution once and pour a 45 mL serving each day; a liter lasts about 22 days. Each serving supplies about 178 mg of magnesium toward your daily intake. Magnesium supports normal muscle and nerve function, energy production, and bone structure.*
*This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
A warm bath or foot soak
Dissolve the powder under running warm water for a bath, or stir it into a basin for your feet. It dissolves completely, so nothing is left at the bottom of the tub.
Homemade magnesium oil
Mix equal weights of powder and warm distilled water to make your own spray for skin, at the strength you prefer. The concentrated brine feels slick on skin, which is why it is called oil; it contains no oil.
Your own bath blends
A plain, single-ingredient raw material for people who mix their own bath salts or sprays and want to know exactly what went in.
You want a supplement you stir straight into a drink.Magnesium Citrate Powder is one level teaspoon a day, with no batch to mix.
For a child under 9. Use it only if a pediatrician directs it: one serving is more than the upper limit for magnesium from supplements for children 1 to 8 (65 to 110 mg a day).
If you have kidney disease. Don’t take a magnesium supplement without your physician’s direction.
How to use
The daily drink follows the directions on the bag. The bath and oil amounts are Greenway’s suggestions. Mix and store everything in glass, ceramic or food-grade plastic, because magnesium chloride corrodes metal.
Daily drink (label directions)
Weigh 33 g. Use a kitchen scale that reads in grams; a spoon doesn’t measure this powder reliably.
Dissolve it in 1 liter of water. Use a glass or food-grade plastic jug and stir until the water is clear.
Take 45 mL once a day. That is 3 tablespoons, with about 178 mg of magnesium.
Cover, label and store it. Keep the jug covered, out of direct sun and out of reach of children; the refrigerator is a good place for it. A liter lasts about 22 days.
For adults and children 9 and older. If you also take another magnesium supplement, an antacid or a laxative, count it too: the upper limit for magnesium from supplements and medications is 350 mg a day for anyone 9 or older.
Bath or foot soak (Greenway’s suggestion)
Run the water. A warm bath of about 40 gallons (150 liters), or a basin with 1 to 2 gallons (4 to 8 liters) for your feet.
Add the powder. ½ to 1 cup under the running water for a bath, or ¼ to ½ cup for a foot soak.
Stir and soak. Stir until it dissolves, then soak for 20 to 30 minutes.
Rinse if you like. Rinse with fresh water if your skin feels tacky afterward.
Homemade magnesium oil (Greenway’s suggestion)
Weigh 100 g of powder into a glass jar.
Add 100 mL of warm water. Use distilled or filtered water, warm but not boiling, and stir until dissolved. Let it cool.
Bottle and label it. Pour it into a glass or plastic spray bottle marked “for skin, not for drinking”. This makes about 165 mL at roughly 50% magnesium chloride hexahydrate by weight. For a milder spray, use 50 g of powder in 100 mL of water.
Patch test, then apply. Try a small area and wait 24 hours. Spray onto arms, legs or the soles of the feet and rub in; rinse off if it feels sticky or tingles.
Keep the two apart. Homemade oil is about 18 times as concentrated as the drinking solution and is not for drinking. Store the two in separate, clearly labeled containers.
Choosing a size
Each bag by what it makes. Servings assume one person taking one 45 mL serving a day from the standard solution; baths use the powder much faster.
What each size of Greenway Biotech Magnesium Chloride USP makes
Size
Standard solution
Daily servings (45 mL)
Homemade oil batches (100 g each)
1 lb (454 g)
About 13.7 liters
About 305, or about 10 months
4
2 lb (907 g)
About 27.5 liters
About 610
9
4 lb (1.81 kg)
About 55 liters
About 1,220
18
8 lb (3.63 kg)
About 110 liters
About 2,440
36
2 × 8 lb (7.26 kg)
About 220 liters
About 4,890
72
The 1 or 2 lb bag suits the daily drink on its own. Choose the 4 or 8 lb bag if you also take regular baths or make oil in batches. Keep the bag sealed between uses.
Compare
Greenway sells magnesium in several forms. Choose by how you want to use it, and follow each product’s own label.
Magnesium Chloride USP compared with other Greenway magnesium products
Option
Form
Labeled use
Choose it when
Keep in mind
Magnesium Chloride USP, this product
Powder, about 12% magnesium
Dietary supplement (a solution you mix). Also used in the bath and for homemade oil
You want one bag for a daily drink, soaks and a spray you make yourself
Who should ask first. Ask your healthcare provider before taking it if you are pregnant or nursing, take medication, or have kidney disease or another health condition. Not for children under 9 unless a pediatrician directs it.
Daily limit. Don’t take more than one 45 mL serving a day unless your healthcare provider directs it. One serving supplies about 178 mg of magnesium; the upper limit for magnesium from supplements and medications is 350 mg a day for anyone 9 or older, so count other supplements, antacids and laxatives. Magnesium chloride can cause loose stools or diarrhea; if it does, stop and ask your healthcare provider.
Medication timing. Take magnesium at least 2 hours before or after an oral bisphosphonate. Take tetracycline or quinolone antibiotics at least 2 hours before, or 4 to 6 hours after, magnesium.
On skin. Homemade oil and bath water are for external use only. Patch test a small area and wait 24 hours before wider use. Keep it out of your eyes and off broken or freshly shaved skin, and discontinue use if irritation occurs. Homemade oil is a concentrated brine: label it and keep it away from children.
Storage. Keep the bag tightly sealed in a cool, dry place, out of reach of children. The powder draws moisture from the air and can clump; break up clumps and reseal.
First aid. Eyes: rinse with plenty of water for at least 15 minutes and see a doctor if irritation persists. Skin: rinse with water. If a child swallows any of it, or anyone swallows homemade oil or a large amount of powder, call Poison Control at 1-800-222-1222.
Frequently asked questions
How much magnesium is in a serving?
About 178 mg. Magnesium chloride hexahydrate is 11.96% magnesium by weight, so the 33 g in the standard liter holds about 3.95 g of magnesium, or 3.95 mg per mL. A 45 mL serving supplies about 178 mg, which is 42% of the 420 mg Daily Value and about half the 350 mg upper limit for magnesium from supplements.
Do I need a kitchen scale?
Yes, for the daily drink and the homemade oil. The directions are in grams because a spoonful of this powder doesn’t weigh the same from one scoop to the next: it packs down, clumps and picks up moisture from the air. A kitchen scale that reads in grams makes every batch the same. For a bath, a measuring cup is fine.
Can I take it with my medications?
Ask your healthcare provider or pharmacist first. The NIH gives timing for known interactions: take magnesium at least 2 hours before or after an oral bisphosphonate, and take tetracycline or quinolone antibiotics at least 2 hours before, or 4 to 6 hours after, magnesium. Some diuretics and long-term proton pump inhibitors change magnesium levels, so your provider may want to check yours.
Why is it called magnesium oil, and why can it tingle?
The concentrated brine feels slick on skin, so it is called oil, but it contains no oil. Some people feel tingling or itching, most often on freshly shaved, dry or broken skin. Use the milder mix (50 g of powder in 100 mL of water), apply it only to unbroken skin, and rinse it off if the feeling is uncomfortable. Stop if irritation occurs.
Why can’t I use metal containers?
Magnesium chloride corrodes many metals, and a solution left in a metal jug or spray bottle can corrode it and pick up metal. Mix and store the drinking solution and any homemade oil in glass, ceramic or food-grade plastic. Scooping the dry powder with a stainless steel spoon is fine; just don’t leave the solution in metal.
The powder has clumped. Is it still usable?
Yes. Magnesium chloride draws moisture from the air, so clumps form whenever the bag is left open or stored somewhere humid. Break them up and reseal the bag right after each use. If the powder has turned damp, it has taken on water, which adds weight, so the 33 g you weigh holds a little less magnesium. Store the bag cool, dry and sealed.
The directions come from the bag label, and the magnesium figures are calculated from them and from the formula weight of magnesium chloride hexahydrate. The statements about magnesium, intake limits and medication timing come from the public sources below; none of them evaluates or endorses this product.
Email questions@greenwaybiotech.com or call (562) 351-5168, Monday to Friday, 9 AM to 3 PM Pacific. We can explain the product, its directions and its documents; for questions about your own health or medications, ask your healthcare provider.
Every order carries our 90-day satisfaction guarantee. Greenway Biotech is family-owned in California since 1989, today in Madera.
I LOVE this magnesium! It is pure and dissolves really well
I LOVE this magnesium! It is pure and dissolves really well.
A
Amanda Pratt
I love it! Very clean and dissolved
I love it! Very clean and dissolved completely!
T
T.P.
Great Quality, Fast Shipping!
This was my first time ordering from this company, and I am very pleased with the quality of the product, as well as the shipping speed. I wish shipping to Hawaii could be free, but it is what it is.
I'll definitely be using this company again for anything they carry that I happen to need!
A
Anonymous
excellent
excellent !
D
Drew Gremillion
Love this mag!
Love this magnesium!
A
Anonymous
Great Product-Great Fast Service
This is the second order I received from this company and I am very pleased. The product is well packaged and it was sent in record time. I will always buy from Greenway Biotech whenever I need more product.
B
Biz Bee
Love the quality of the product top
Love the quality of the product top notch
A
Anonymous
High Quality !
High Quality and no fillers. Very satisfied !
A
Anonymous
DISSOLVE
DISSOLVE GREAT
Z
Zeljka Groth
excellent
The product is excellent
D
Dinah Lindarin
Perfect supplement on multiple levels
I'm very happy with this product!
I was looking for a magnesium supplement that was absorbable, cleanly sourced and affordable (!). There are so many forms that I started my research there. I discovered that magnesium chloride is 90% absorbable! As opposed to mag oxide - 4% and mag L-threonate - 7%... Mag citrate is better absorbed than most (couldn't find percentage but still not as good as mag chloride) but it's mainly used as a laxative (oops took too much doh!).
So I looked for mag chloride, found this company and was amazed to discover that they sell it in bulk powder! This is so awesome as it 1) allows me to manage my own dosage 2) can be added to drinks which I prefer to taking capsules 3) can be used to make mag oil and 4) much more affordable!
Add to that the fact that it's cleanly sourced and duly tested...
This is now my go-to source for magnesium. Thank you Greenway!
C
Cynthia
I am happy with the Organic Magnesium Chloride
I am happy with the Organic Magnesium Chloride USP. I just recently learned how to use it dosing it in small dosages throughout the morning and afternoon. I think I am actually restoring my body stores. I like the cost savings over Mag Chlor in dropper bottles. I feel lucky to have access to something that is economical for my health over the long term.
I
Irene
Greenway's Magnesium Chloride is the most pure and absorption is quick!
Greenway's Magnesium Chloride is the best! I use it to soak my feet and to make Mag Oil. I put the Mag Oil on my arms, legs and neck every night.
F
Francisco
El mejor
El mejor servicio
R
Robin Hancock
Wonderful!
Great product and easy to use! Very happy with the product!
H
Helen Hamann
Great!
B
Blanca
Magnesium Chloride game changer
Amazing product. I sleep much better now.
i
iris tirado
Cloruro de Magnesio USP
Ecxelente producto de GREENWAY BIOTECH, me siento confiada trabajar ese producto, ya que puedo preparar cloruro de magnesio líquido, aceite de magnesio, loción de magnesio y jabón de magnesio, todo queda espectacular y lo más importante es que funciona muy bien.
I
Irene F. Block
Greenway's Organic Magnesium Chloride is the best!
This is the only mag chloride I use. I put it on my feet when I don't have time to soak and I make mag oil to spray when I feel the need. I also make it and give it as gifts because I find it so healing with helping me to detox.
G
Gloria Parker
The best
I have used other magnesium, but nothing helps me as much as your product. It is the best.
L
L.M.
Muy buen producto.
A
Anne Olson
I love it!! Couldn’t live without it!! Thank you!
H
Halina Nosol
magnesium chloride
very good product ! good price.
C
Christine Pappas
This is helped clear up
A very rare skin condition that my family has been dealing with for 40 years. Thank you!!
P
Penny Breeden
Great product
I use this to make magnesium oil to put on my legs and other muscles that cramp. I don’t seem to keep enough magnesium in my body. I don’t understand why so I use this besides taking an oral supplement. This product is easy and pleasant to use.
P
Paul Jankauskas
Best food grade magnesium chloride I have ever used!
I have more energy
I sleep better
It balances my blood sugar
It helped me loose 10 pounds...
This salt is a super antioxidant when I use it as directed on the bag...
I received my order in 3 days
Thank you Greenway Biotech
Paul Jankauskas
A
Asha Rado
Great service
I did receive the wrong item on first delivery which was a quick delivery and when I reached out to customer service they were so helpful and apologized. They sent the correct item out asap and told me to keep the wrong item. Overall great experience with this company.
A
Anne Olson
All excellent!
The whole ordering experience was wonderful! Service and follow up are great! I now have 3 bags of magnesium as I never want to run out of it! Thank you for your excellent product, service & follow up! Anne
M
Mary Rupert
Magnesium Chloride Oral
Great. I sent in a question, and I had a phone call with the answer by the next day. I've been using your magnesium chloride flakes for many years. It relieves my night leg cramps immediately so I can go right back to sleep. Am ready to use recipe for daytime use.
J
Jerry Soll
Different taste
I have been buying this product for years and love it. I normally buy it in one pound bags. This time I purchased a 4 pound bag to get free shipping. There is a very different taste to the product. Has something changed in the product ? Not complaining ~ ~ ~ I just want to know what has changed.
My MSM is decreasing my osteoarthritis pain, especially in my hands
My product arrived intact. I started taking it as soon as I went into the kitchen. I mixed it with my daily Metamucil, but there was no discernible taste. I am working on making it a habit each morning. The pain from my osteoarthritis, especially in my hands, is decreasing. I expect it to continue to improve. Thank you for my MSM.
You did not send me MSM Powder, you sent me Magnesium Chloride powder. I tried contacting you 3 times, by email & phone and you didn't have the courage & honesty to return my messages & rectify the situation. I even offered to text you a photo of the mag chloride.
