Is MSM Stable in Water? A Comprehensive Chemical Breakdown

November 26, 2025 •

4 min read

MSM, or methylsulfonylmethane, is a naturally occurring organosulfur compound that is highly water-soluble, dissolving readily in aqueous solutions. This innate property is crucial for understanding the answer to the question, is MSM stable in water, for use in various applications, from industrial solvents to dietary supplements.

Quick Summary

Methylsulfonylmethane (MSM) is both chemically stable and highly soluble in water, forming a reliable and inert solution. It does not significantly degrade in water under normal conditions but can volatilize at high temperatures.

Key Points

High Solubility: MSM is highly soluble in water due to its polar sulfonyl group, which easily forms hydrogen bonds with water molecules.
Chemical Inertness: The molecule is chemically stable and inert because its sulfur atom is in a fully oxidized state, making it resistant to further chemical change.
Thermal Stability: While MSM can volatilize during high-heat cooking, it does not chemically break down or degrade in water at normal or elevated temperatures.
Vulnerability to Strong Agents: MSM's stability can be compromised by strong oxidizing agents, though this is not a concern under normal supplement preparation.
Natural Origin: MSM is a naturally occurring compound that cycles through the environment via water, demonstrating its inherent stability in aqueous environments.
Supplement Reliability: For supplements, MSM's high water stability and solubility ensure consistent and effective delivery when dissolved in liquid.

Understanding the Chemical Nature of MSM

Methylsulfonylmethane (MSM), also known as dimethyl sulfone or DMSO2, is a small, organic, sulfur-containing molecule. Its chemical formula, $C_2H_6O_2S$, and its structure—two methyl groups attached to a central sulfonyl group—are key to its properties. The sulfur atom in the sulfonyl group is already in its highest oxidation state, making the molecule resistant to further oxidation and inherently stable. This structural feature is a primary reason for its high chemical inertness and reliability.

The High Solubility of MSM in Water

MSM is known to be a white, crystalline powder that is odorless and highly soluble in water. The high polarity of the sulfonyl group allows it to form strong hydrogen bonds with water molecules, facilitating its dissolution. A solubility of 150 g/L at 20°C highlights its excellent ability to mix thoroughly with water. This high solubility is important for several reasons:

Easy Absorption: When consumed as a dietary supplement, its high solubility ensures it dissolves effectively in the body's aqueous environment for rapid absorption.
Consistent Dosing: For supplement manufacturers, high solubility ensures a uniform and consistent concentration when mixed into liquid products.
Industrial Applications: It makes MSM a useful solvent for various substances in industrial processes, especially at high temperatures.

Is MSM Stable in Water Under Normal Conditions?

Under normal conditions, such as standard room temperature and typical pH levels, MSM is extremely stable in water and will not degrade. The integrity of the molecule is preserved, and it remains a reliable source of organic sulfur. This stability is a significant advantage for users of dietary supplements, as they can be confident that the MSM dissolved in their drink or food will remain effective over time.

However, it is crucial to understand that while the compound is chemically stable, its physical state can change with temperature. Some sources mention that MSM can volatilize (turn to gas) during high-temperature cooking, which can reduce its concentration in food. This is a physical process of evaporation, not a chemical breakdown, and it is most relevant to cooking rather than simple dissolution in water for consumption. For example, if you add MSM powder to a hot beverage, some may be lost in the steam, but the dissolved portion remains stable.

Factors That Could Affect MSM Stability

While MSM is largely stable, there are a few conditions under which its stability could be compromised:

Strong Oxidizing Agents: As a sulfone, MSM is generally resistant to oxidation, but it can react with very strong oxidizing agents. However, this is not a concern for normal tap or bottled water.
Extreme Freezing and Concentration: As shown in some cooling agent experiments, very high concentrations of MSM in water can affect the freezing and thawing processes, and the solution may not fully re-dissolve or homogenize.
Long-term Storage in Incompatible Containers: The stability of any chemical can be affected by long-term storage in improper containers or in the presence of incompatible materials.

MSM vs. DMSO: Stability in Aqueous Solutions

Understanding the relationship between MSM and its precursor, dimethyl sulfoxide (DMSO), helps clarify its robust stability. While DMSO is a potent solvent, MSM is a more oxidized and chemically inert derivative with different properties.


Feature	Methylsulfonylmethane (MSM)	Dimethyl Sulfoxide (DMSO)
Chemical State	More oxidized form.	Less oxidized precursor.
Chemical Stability	Highly stable and chemically inert.	Generally less stable, can be further oxidized to MSM.
Solubility in Water	Highly water-soluble.	Highly water-soluble.
Physical Properties	Odorless crystalline powder.	Oily liquid with a characteristic garlic-like odor.
Reactivity	Less reactive than DMSO.	More reactive; potent solvent.

The Natural Water Cycle and MSM

Interestingly, MSM is a natural part of the Earth's sulfur cycle. It originates from marine phytoplankton, which release dimethyl sulfide (DMS) into the atmosphere. DMS is then oxidized by ozone and UV light to form DMSO and MSM. These compounds are highly water-soluble and return to the Earth's surface in rain, where they are absorbed by plants. This natural process underscores MSM's inherent stability in water, as it has been part of the global hydrological cycle for millennia.

Conclusion: The Final Verdict on MSM Stability in Water

Based on its chemical structure, high polarity, and observed properties, MSM is exceptionally stable in water under typical conditions. Its high solubility ensures it dissolves readily, forming an inert solution that remains consistent over time. While temperature extremes can cause physical volatilization, the chemical integrity of the MSM molecule in an aqueous environment is very strong. This makes MSM a reliable and safe compound for use in dietary supplements and various industrial applications. For more on MSM, see the comprehensive overview provided by the NIH.

Frequently Asked Questions

MSM is thermally stable, so it will not degrade chemically in a hot drink. However, some of the MSM can physically volatilize (evaporate) with the steam, slightly reducing the amount of the compound in the liquid.

Yes, you can pre-mix MSM with water for later use. The compound is very stable in aqueous solutions and will not break down over a short period. It is still best to store it in a cool, dark place.

MSM (dimethyl sulfone) is the more oxidized and chemically inert derivative of DMSO (dimethyl sulfoxide). A key difference is that DMSO has a characteristic garlic-like smell, while MSM is odorless.

MSM is stable over a wide range of pH levels, including both acidic and alkaline environments, making it reliably stable in most types of water.

Pure MSM is an odorless, white crystalline powder. If your supplement has a noticeable, pungent odor (often described as garlic-like), it could be contaminated with unoxidized DMSO.

Freezing does not degrade MSM chemically. However, in experiments using high concentrations of MSM, the frozen mixture may not fully re-dissolve upon thawing.

No, MSM does not lose its potency in water under normal conditions over a reasonable period. Its chemical stability ensures that the dissolved compound remains intact and effective.