People bring me the bottle in clinic: "This one says glycinate, the last one said citrate, and the balm says chloride. Which magnesium should I actually buy?"
The short answer: It depends on the job. Glycinate is the gentlest form to swallow, and it has the most direct sleep research. Citrate is the best-absorbed form you swallow, and it can loosen your bowels. Chloride is the form that goes on skin, in balms, oils and bath flakes. Oxide is cheap, and it absorbed poorly in trials. Pick by the job, not by a ranking.
By Dr. Doug Strobel, MD, a board-certified neurologist who formulated Dr. Doug's balms. Last reviewed October 13, 2026.
Does it really matter which magnesium I buy?
The labels are confusing, and nobody should waste money on a bottle that does very little. I read these trials as a board-certified neurologist, and I made a magnesium balm for my clinic patients and for myself first. I wanted to formulate a product unlike others on the market. My goal: the most magnesium chloride possible that still absorbs in completely, with no sting and no grit, in a handful of clean, non-toxic ingredients. Only goodness and nourishment that truly helps. The magic happens when you massage it in completely.
Why does the form of magnesium matter?
Magnesium always comes attached to a partner, like glycinate, citrate, chloride or oxide. That partner changes how well it absorbs and how your stomach reacts.
Is magnesium oxide worth buying?
Magnesium oxide is the cheapest and most common form on the shelf. In a careful trial, it did no better than a placebo.
Walker and colleagues ran that trial in 46 healthy adults. It was randomized and double-blind, which means people were sorted by chance and nobody knew who got which pill. Each person took 300 mg of elemental magnesium a day for 60 days. (Elemental means the actual magnesium part, not the partner.) The trial compared three forms. One was an amino-acid chelate, the family glycinate belongs to. The others were citrate and oxide. At 60 days, the citrate and chelate groups absorbed much more than the oxide group (P = 0.033). The authors wrote that oxide "resulted in no differences compared to placebo." [1]
Werner and colleagues found the same pattern in 2019 with a different setup. Fourteen healthy men took one 400 mg dose of citrate or oxide. Citrate raised the magnesium in their urine over 24 hours. Oxide did not. Blood magnesium was higher with citrate at 4 and 8 hours. [2]
Two studies, one answer. If your bottle says oxide, you may be getting very little for your money.
Is magnesium citrate the best absorbed?
Yes, citrate is the best-absorbed form you swallow in head-to-head tests. The trade-off is that it can loosen your bowels at higher doses.
In Walker's trial, citrate gave the highest average blood magnesium of any form tested. That was true after one dose (P = 0.026) and after 60 days (P = 0.006). [1]
Citrate pulls water into the bowel, which is why it is also sold as a laxative. It is a good daytime choice. At night, a 2 a.m. bathroom trip is not what you want.
Is magnesium glycinate best for sleep?
Glycinate is the best-studied form for sleep. The effect is real, but it is small.
Glycinate is magnesium bound to glycine, an amino acid, one of the building blocks of protein. It is easy on the stomach.
Schuster and colleagues published a trial in 2025. It was randomized, double-blind and placebo-controlled. 155 adults who said they slept poorly took either 250 mg of magnesium as bisglycinate or a placebo. By week 4, their scores on an insomnia survey dropped more with magnesium: 3.9 points versus 2.3 points (p = 0.049). [3]
The authors called the effect small (Cohen's d = 0.2, a standard way to measure size) and the benefit "modest." No other mood or mind measure changed between the groups. One early hint stood out. People who ate less magnesium to begin with improved more. Anyone who tells you glycinate transforms sleep has not read the trial.
What is magnesium chloride used for?
Chloride is the form used in skin products, and it's the best choice for topical magnesium. It dissolves easily and spreads well in a balm, an oil or a bath.
Swallowed, chloride holds its own too. A 2001 study tested four US magnesium products. Chloride absorbed much better than oxide, and about as well as two other forms, lactate and aspartate. [5]
Research on magnesium through skin is small, mostly in adults, and still debated. A chloride balm works right where you put it: the calf you are rubbing, the tight shoulder, the slow few minutes at the end of a long day. It does not replace oral magnesium if you truly don't get enough from food.
If your goal is sleep, glycinate by mouth has the most trials. My balm hasn't been tested in a sleep trial yet. But in our own 14-day customer survey of Magnesium Balm, 93% reported improved relaxation and sleep. I use it at night myself, and my patients tell me the same. Many people use both, and that is fine.
Magnesium glycinate vs citrate vs chloride vs oxide: comparison table
The four forms differ in their partner, how you use them and how well they absorb.
| Glycinate | Citrate | Chloride | Oxide | |
|---|---|---|---|---|
| Bound to | Glycine | Citric acid | Chloride | Oxygen |
| How it is used | Oral | Oral | Topical (balms, oils, flakes) | Oral |
| Absorption | Good, gentle | Best oral form tested [1][2] | On skin: research is small and debated | No better than placebo in a trial [1] |
| Gut effect | Minimal | Laxative at higher doses | None, it is not swallowed | Laxative at higher doses |
| Best for | Evening use, sensitive stomachs | General intake | Massaging into tired muscles, a wind-down routine | Little, for general intake |
| Key evidence | 155-adult trial: modest sleep benefit, d = 0.2 [3] | Highest serum magnesium of forms tested [1] | Local, hands-on use | No difference vs placebo [1] |
So which magnesium should you buy?
Buy the form that matches your goal.
- You want help sleeping. Take oral glycinate in the evening. Expect a modest effect, and more of one if your diet is low in magnesium.
- You want more magnesium and your stomach is fine. Take citrate. Start low, because the laxative effect grows with the dose.
- You want something for tired legs, a tight neck or a wind-down routine you can feel. Use a magnesium chloride balm, massaged in right where you feel it.
- You want the cheapest bottle on the shelf. Read the label first. If it says oxide, the trials say you may be buying very little.
- You are treating a diagnosed deficiency. Talk with your own doctor. The form and dose should be theirs to choose.
New to magnesium balm? Start with What Is Magnesium Balm and How Does It Work? If restless legs are why you are here, read Best Magnesium for Restless Legs.
How to use magnesium balm: pick, rub, repeat
- Pick your spot. Tired calves, sore feet or a tight neck. Start with a thin layer. A little goes a long way.
- Rub it in. Cover the spot that bothers you, plus about 5 inches above, below and all the way around it. Massage until it disappears.
- Repeat. Any time of day works. Skip broken or irritated skin.
My balm is magnesium chloride in organic olive oil, organic coconut oil, beeswax and organic shea butter, with peppermint and lavender essential oils and vitamin E. It comes as a 2.5 oz twist-up stick, an 8 oz jar and a 0.5 oz mini.
Picture it. The right bottle is on your counter. At the end of the day, two minutes on your calves, and nothing left on your hands.
Based on a 14-day consumer perception survey; respondents per check-in varied.
Related reading
Frequently asked questions
Is magnesium glycinate better than citrate?
Glycinate is gentler and has a sleep trial behind it. Citrate absorbed best in head-to-head trials, and it can loosen your bowels. Neither is better across the board; pick by the job.
Which magnesium is best for sleep?
Oral magnesium glycinate has the most direct sleep research. A 2025 trial in 155 adults with poor sleep found a small but real drop in insomnia scores. People who ate less magnesium to begin with improved more.
Magnesium chloride vs glycinate: which is better?
Magnesium chloride and magnesium glycinate are used in different ways. Glycinate is swallowed. Chloride is the form in balms, oils and bath flakes. Swallowed chloride absorbed about as well as other good forms in a 2001 study. If sleep is your goal, oral glycinate has more direct research.
Which magnesium is best absorbed through skin?
Magnesium chloride is the form used in skin products, because it dissolves easily. Research on magnesium through skin is small and still debated. If you want more magnesium overall, choose an oral form. Use a chloride balm for what it does right where you put it.
Which magnesium is best for leg cramps?
Pick the form for other reasons, because no form of magnesium has strong research for leg cramps. A 2020 Cochrane review, a large summary of trials, found magnesium pills are unlikely to give older adults meaningful protection from muscle cramps, whatever the form.
Is magnesium oxide bad for you?
Magnesium oxide is not harmful for most healthy adults. It is just poorly absorbed. In a 60-day trial of 46 adults, magnesium oxide did no better than a placebo. It is common because it is cheap.
Can you use a magnesium balm and take magnesium at the same time?
Yes. Many people use a magnesium balm and take oral magnesium, for different reasons. The pill is for intake, and the balm is for massaging into tired muscles. If you have kidney disease or take medicine that affects magnesium, ask your own doctor before taking oral magnesium.
Sources
- Walker AF, Marakis G, Christie S, Byng M. Mg citrate found more bioavailable than other Mg preparations in a randomised, double-blind study. Magnesium Research, 2003. PMID 14596323
- Werner T, Kolisek M, Vormann J, et al. Assessment of bioavailability of Mg from Mg citrate and Mg oxide by measuring urinary excretion in Mg-saturated subjects. Magnesium Research, 2019. PMID 32162607
- Schuster J, Cycelskij I, Lopresti A, Hahn A. Magnesium bisglycinate supplementation in healthy adults reporting poor sleep: a randomized, placebo-controlled trial. Nature and Science of Sleep, 2025. PMID 40918053
- Garrison SR, Korownyk CS, Kolber MR, et al. Magnesium for skeletal muscle cramps. Cochrane Database of Systematic Reviews, 2020. PMID 32956536
- Firoz M, Graber M. Bioavailability of US commercial magnesium preparations. Magnesium Research, 2001. PMID 11794633
This article is educational and is not medical advice. Dr. Doug's products are cosmetic and are not intended to diagnose, treat, cure or prevent any disease.