E314 - Guaiacum

At a glance

• What it is: a resin from the guaiac wood tree, used as an antioxidant.
• What it does: helps protect fats, oils, and flavors from oxidation.
• How common: rarely used today compared with other antioxidants.
• Label names: may appear as guaiacum, guaiac resin, or gum guaiac.
• Diets: not a source of calories; used in very small amounts.

Why is Guaiacum added to food?

Manufacturers add guaiacum to slow oxidation, the chemical reaction that causes fats to go rancid and flavors to fade. In the Codex system (global food standards), guaiacum is listed as an antioxidant allowed at good manufacturing practice (GMP) levels, meaning only the minimum needed is used.¹

What foods contain Guaiacum?

Guaiacum is uncommon on modern labels. Where used, it has historically appeared in fatty foods (like certain oils and shortenings) and flavor-rich products that are sensitive to air and heat. Codex lists it as an antioxidant for selected food categories under GMP, so actual use depends on a country’s rules and a brand’s recipe choices.¹

What can replace Guaiacum?

Food makers often choose other antioxidants that are easier to source or have clearer regulatory status. Common alternatives include:

• Natural options: ascorbic acid, tocopherol-rich extract, and extracts of rosemary.
• Synthetic options: butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), and propyl gallate.
• Helpers: acids like citric acid can boost antioxidant performance in some formulas.

How is Guaiacum made?

Guaiacum is obtained from the wood of the guaiac tree. The resin is collected and purified—often by solvent extraction and physical refining—to remove wood solids and concentrate the antioxidant components.² The finished material may be supplied as a brittle solid or powder for easy blending into foods.²

Is Guaiacum safe to eat?

An international expert committee (JECFA, run by FAO/WHO) evaluated guaiacum and assigned an “ADI not specified” when used according to good manufacturing practice. This phrase indicates low toxicity at the small amounts needed for its technical effect.² Codex also lists guaiacum as an antioxidant allowed at GMP levels, which limits use to the minimum effective amount.¹

Does Guaiacum have any benefits?

In foods, the benefit is simple: it helps keep fats tasting fresh and flavors stable during shelf life. By slowing oxidation, antioxidants can also help protect color and certain sensitive nutrients in some recipes.

Who should avoid Guaiacum?

• Anyone with a known sensitivity to botanical resins or balsams should check labels and consult a clinician if uncertain.
• If your healthcare provider has advised you to avoid specific plant resins, follow that guidance.
• As with any additive, people who prefer fewer additives can choose products that use alternatives listed above.

Myths & facts

• Myth: “Guaiacum” on a medical test means it’s in my food.
  Fact: Some stool tests (gFOBT) use guaiac as a reagent; this is separate from its occasional use as a food antioxidant.³
• Myth: Guaiacum is the same as every “guaia-” ingredient.
  Fact: Guaiacum (a resin) is different from similarly named compounds such as guaiacol; names that look alike may be unrelated.

Guaiacum in branded foods

You are unlikely to see guaiacum often on today’s labels. If present, look for “guaiacum,” “guaiac resin,” or “gum guaiac.” Because many companies now favor other antioxidants, guaiacum appears mainly in niche or legacy formulations. Availability and labeling can vary by country and brand.

References

Footnotes

1. Guaiac resin (INS 314) — Codex GSFA Online. https://www.fao.org/gsfaonline/additives/details.html?id=314 ↩ ↩² ↩³

2. Guaiac resin — WHO/FAO JECFA (Safety evaluation and specifications). https://www.inchem.org/documents/jecfa/jecmono/v35je05.htm ↩ ↩² ↩³

3. Fecal occult blood test (guaiac-based) — MedlinePlus, NIH. https://medlineplus.gov/lab-tests/fecal-occult-blood-test-fobt/ ↩