Xanthan Gum

Overview

Xanthan gum is a high-molecular-weight polysaccharide produced by fermentation. A bacterium called Xanthomonas campestris eats sugar (usually glucose from corn) and excretes long, branched sugar chains that, when purified and dried, become a pale cream-colored powder. It is one of the most-used thickeners in food, cosmetics, and pharmaceuticals — you have eaten it many times this week.

In water it forms thick, viscous gels at remarkably low percentages. As little as 0.2% will noticeably thicken a 100 ml water-based formula. It is anionic (negatively charged) at typical use levels, which is worth noting because it can interact with cationic ingredients like polyquats and BTMS in certain ratios.

Xanthan gum comes in three main DIY-relevant grades that give meaningfully different results:

• Standard / Regular xanthan gum — slightly grey-cream powder, produces slightly cloudy gels with a noticeable slippery, slimy slip. The cheapest option and the most thickening power per gram.
• Xanthan gum Clear (Soft, Pristine) — refined to produce crystal-clear gels and a softer, less slimy skin feel. Slightly more expensive, slightly less thickening power.
• Xanthan gum NF — pharmaceutical-grade, very pure, used in tablets and medical products. Functionally similar to standard for skincare purposes.

For most DIY cosmetic use, the difference between Standard and Clear/Soft is what matters most — the latter is worth the small price increase for face products.

What it does in a formula

Primary role: thickener of water-based formulas — toners, mists, serums, shampoos, cleansing gels. It thickens fast, holds its thickness, and is shelf-stable for years.

Secondary roles: emulsion stabilizer (a tiny 0.1-0.2% in a lotion helps prevent separation by thickening the water phase), particle suspender (keeps exfoliating beads, clays, or pigments evenly distributed), and a film-former that gives a subtle hold to styling gels.

How to use

Use it at 0.1-1% of the total formula. Typical ranges:

• 0.1-0.2%: emulsion stabilizer, light film-former
• 0.2-0.4%: thickener for serums, toners, hair mists
• 0.5-1%: hair gel, styling gel, thick suspending gel for clay or exfoliants

The way you disperse xanthan gum matters more than the percentage. Never sprinkle dry xanthan straight into water — it instantly forms a gummy clump (called “fish eyes”) that takes hours to dissolve. Instead:

1. Pre-disperse in glycerin, propanediol, or another humectant: stir the xanthan into 5-10 times its weight of glycerin until smooth, then add this slurry to your water phase while stirring.
2. Or pre-disperse in oil: xanthan does not dissolve in oil but it cannot clump in it, so you can mix it into your oil phase first and then add the water phase.
3. Or sprinkle very slowly while running a stick blender at low speed.

Fully hydrated gel forms within a few minutes of contact with water at room temperature, but reaches full viscosity after sitting for 12-24 hours. Stable across a very wide pH range (roughly 3-12).

It is shear-stable — you can mix and blend without losing viscosity (unlike carbomer, which thins under high shear).

It is electrolyte-tolerant up to a point — it handles small amounts of salt fine, but high electrolyte loads (above 1-2% salts) can reduce thickening.

For the Clear/Transparent grade specifically, working ranges run slightly tighter: up to 1% in shower gels and shampoos, capped at 0.5% in emulsions, with 0.2-0.5% for light body in lotions, 0.5-1% for light gels, and 1-2% for clear medium-density gels.

Best for / Worst for

Best for: water-based serums, hair gels, suspending gels for clays and exfoliants, emulsion stabilization, mist-style toners, aloe-vera gels, cleansing gels, shampoos.

Worst for: ultra-clear gel products (use Clear-grade or HEC instead — standard xanthan is slightly cloudy), gels that need a perfectly silky, non-slimy feel (sclerotium gum is better), and high-electrolyte formulas like deodorant sprays.

Common pitfalls

The biggest pitfall by far is clumping (fish eyes). Dump dry xanthan into water and you get little gummy beads that stay forever. The fix is always pre-dispersion in glycerin or oil.

Second pitfall: the slimy feel. Standard xanthan, especially above 0.5%, has a noticeably slippery, slightly stringy slip that some people dislike. Switch to Clear or Soft grade for a softer feel, or pair with HEC or sclerotium for a smoother gel.

Third: using too much. 1% xanthan in a water-based product is thick — sometimes too thick to flow. Start low (0.3%) and add more if needed.

Fourth: assuming all grades are identical. They are not. The Clear/Soft grades cost about 30-40% less thickening power per gram than standard, so a recipe written for one grade will not behave the same with the other.

Fifth: pH extremes outside 3-12. Within that range it is rock-solid. Outside it, the gel breaks down.

Substitutes

• Sclerotium Gum — smoother, less slimy, more elegant skin feel. Slightly more expensive.
• Hydroxyethylcellulose (HEC) — crystal-clear gels, completely non-slimy, used at higher percentages (0.5-2%).
• Carbomer / Sepimax ZEN — synthetic, crystal clear, very different gel feel, more expensive.
• Acacia / Gum Arabic — gentler thickening, more skin-feel-friendly, but much less thickening power.
• Konjac Gum, Cellulose Gum — niche alternatives, food-grade, similar broad behavior.