Magnesium Chloride vs. Magnesium Hydroxide in Skincare: A Complete Guide
Magnesium has found its way into wellness routines for years and years. From bath soaks to supplements but in recent times, it’s also become a key player in skincare. You might see it listed on labels in two main forms: magnesium chloride and magnesium hydroxide. Though they sound similar, these two ingredients behave very differently on the skin.
Whether you’re exploring magnesium for sleep support, sore muscles, or natural odor control, it’s important to know which form does what. In this guide, we’ll walk through their origins, benefits, and how to choose the right one for your skincare goals.
Estimated reading time: 5–6 minutes
1. What is Magnesium Chloride?
Magnesium chloride is a naturally occurring mineral salt, most often derived from ancient seabeds or evaporated salt lakes, such as the Dead Sea or the Zechstein seabed in the Netherlands. It’s composed of magnesium and chlorine, both essential elements found in nature and within the human body.
When magnesium chloride is dissolved in water, it creates a concentrated, slippery brine often called “magnesium oil.” While it has an oily feel, it contains no actual oil it’s simply a highly saturated saltwater solution. This form is prized for its ability to deliver magnesium directly through the skin, a method known as transdermal absorption.
In topical skincare, magnesium chloride is typically used to help restore magnesium levels, especially in people who are deficient or depleted due to stress, poor sleep, diet, or overexertion. It has gained popularity in wellness routines as a natural remedy for muscle aches, tension, and sleep difficulties offering support that bypasses the digestive system entirely.
You’ll often find magnesium chloride in balms, sprays, foot soaks, and lotions, especially those designed to ease sore muscles, cramps, or nervous system overload. It’s become a favourite among athletes, parents, shift workers, and anyone needing gentle body support at the end of the day.
This mineral compound is generally well-tolerated, but it can cause a mild tingling, itching, or stinging sensation for some people particularly if applied to shaved skin, broken skin, or areas that are already irritated. This is not an allergic reaction, but more of a natural response to the salt concentration. Many formulas, including my own, blend magnesium chloride with nourishing oils, herbs, or butters to cushion the intensity and provide a more comfortable experience.
What sets magnesium chloride apart is its bioavailability; its ability to be used by the body once absorbed. Unlike some topical ingredients that simply sit on the surface, magnesium chloride works a little deeper, helping support the nervous system, muscles, and overall mineral balance.
2. Benefits of Magnesium Chloride in Skincare
Magnesium chloride is more than just a mineral. When used topically, it offers a range of body-supporting benefits that go beyond the surface.
1. Muscle Recovery and Relaxation
Magnesium plays a role in muscle function, nerve signals, and stress response. Applying it directly to the skin can help relax tight or overworked muscles, making it a favourite among people with tension, cramps, or soreness.
2. Sleep Support
Because of its calming effect on the nervous system, many people use magnesium chloride in evening skincare routines to promote better sleep. A magnesium balm applied to the feet, legs, or shoulders can become a simple wind-down ritual.
You can find magnesium chloride in our handcrafted Arnica & Magnesium Recovery Balm. It’s designed to soothe tired muscles and support deep rest, using a thoughtful blend of magnesium and arnica.
3. Headache and Tension Relief
Some find relief from headaches or stress tension by applying magnesium chloride to the back of the neck or temples. Though not a cure-all, its calming action can help ease the edge of daily overwhelm.
4. Skin-Friendly Absorption
Unlike oral magnesium, topical magnesium chloride doesn’t have to go through the digestive system. For people with sensitive stomachs or poor absorption, it offers a more direct route to increasing magnesium levels.
3. What is Magnesium Hydroxide?
Magnesium hydroxide is a white, odorless powder that is most often found in natural deodorants. It has a very different purpose from magnesium chloride. Rather than being absorbed into the body, magnesium hydroxide works on the surface of the skin by neutralising bacteria that cause odor.
It’s a gentle alternative to baking soda, which is often used in DIY or natural deodorants but can cause irritation for some. Magnesium hydroxide helps maintain a healthy pH level under the arms while still allowing the skin to breathe.
It’s not used for muscle relief, tension, or magnesium absorption; it’s all about keeping the skin clean and odor-free in a non-disruptive way.
Magnesium Hydroxide powder
4. Benefits of Magnesium Hydroxide in Skincare
Magnesium hydroxide is best known as a natural deodorant active, but it also has a few bonus qualities that make it a quiet hero in simple skincare formulas.
1. Gentle Odor Control
Magnesium hydroxide helps to prevent the growth of odor-causing bacteria without blocking sweat. This means your body can still cool itself naturally, while staying fresher for longer.
2. Ideal for Sensitive Skin
Unlike baking soda, which can be harsh and pH-disruptive, magnesium hydroxide is much less irritating, even for those with reactive or allergy-prone skin. It’s often recommended for people switching from conventional deodorants.
3. Surface-Level Action
Magnesium hydroxide doesn’t absorb into the bloodstream. Instead, it acts on the top layer of skin, making it a good choice for products where long-term mineral absorption isn’t the goal.
4. May Help Calm Minor Irritation
Its mild alkalinity can help soothe inflammation in some skin types, which is why it’s sometimes used in creams for acne-prone skin or in toothpaste for sensitive gums.
5. Key Differences Between Magnesium Chloride and Hydroxide
Here’s a quick side-by-side comparison to highlight how different these two ingredients really are:
| Feature | Magnesium Chloride | Magnesium Hydroxide |
|---|---|---|
| Source | Salt lakes or sea water | Mineral powder |
| Solubility | Dissolves in water | Does not dissolve in water |
| Main Purpose | Transdermal absorption | Surface-level deodorant action |
| Skin Benefits | Eases tension, supports sleep | Neutralizes odor, gentle pH balance |
| Common Uses | Balms, sprays, magnesium oil | Deodorants, acne treatments |
| Absorption | Absorbs into bloodstream | Stays on the surface |
| Risk of Irritation | Can sting on broken skin | Generally well tolerated |
6. Which One Belongs in Your Skincare Routine?
Choosing between magnesium chloride and magnesium hydroxide comes down to what you’re hoping to support.
- If your goal is to relax tight muscles, sleep more deeply, or ease daily tension, magnesium chloride is the better choice. It’s meant to be absorbed and work with your body from the inside out.
- If you want gentle odor protection that respects your skin’s balance, magnesium hydroxide is ideal. It’s mild, effective, and doesn’t interfere with how your body sweats naturally.
They’re not interchangeable but they’re both valuable, depending on the role they play.
7. Why I Use Magnesium Chloride in My Balm
When I began making my Arnica & Magnesium Recovery Salve, I wanted it to do more than coat the skin. I wanted it to be soothing, functional, and supportive, especially for tired muscles, restless nights, and post-exercise recovery.
Magnesium chloride gave me exactly that. It blends beautifully with arnica, which helps with tension and minor aches, and it absorbs into the skin to offer deeper support than a surface balm alone.
I didn’t choose magnesium hydroxide because my goal wasn’t odor control it was rest and relief. Magnesium chloride makes the balm more than skin deep. It makes it part of a routine that supports how you feel, not just how you look.
Final Thoughts: Choosing the Right Form for Your Skin
Magnesium is one of those ingredients that quietly supports your body in big ways. But like most things in skincare, the form matters.
Magnesium chloride is absorbed through the skin, making it great for recovery and relaxation. Magnesium hydroxide sits on the skin’s surface, making it excellent for keeping you fresh and balanced.
Whether you’re crafting your own product or shopping for one that suits your needs, understanding the difference helps you make choices that are more aligned with your body.
Choose what your skin—and your routine—actually need. And if you're ever unsure, start small. Test gently. Listen to how your body responds. That’s where the real self-care begins.
Want to dive deeper into clean skincare? Browse more ingredient guides here or explore our Substack, The Unfiltered Way, where we share honest insights into non-toxic living, product-making, and what it means to care for your skin naturally.
