Colloidal gold in the body: absorption, evidence and risks

August 28, 2026

Neutrale Darstellung von Goldpartikeln und möglichen Wegen im Körper

At a glance: There is no single effect of gold in the body. Metallic gold, gold salts and engineered nanoparticles differ, and evidence about one form cannot be assumed to apply to a retail colloidal dispersion.

What a product description leaves unanswered

A PPM value expresses a proportion whose basis must be specified. It does not reveal particle size, the dissolved fraction, surface chemistry, aggregation or impurities. Nor does it by itself state the total quantity in a bottle or the amount associated with a particular use.

Colour and clarity are not reliable substitutes for analytical characterisation. Similar-looking dispersions can contain different materials. Without suitable product data, confident claims about absorption or distribution are not justified.

Absorption and distribution depend on the material

Cell, animal and material studies show that gold's behaviour depends on its chemical form, particle characteristics and route of exposure. Material passing through the digestive tract is not equivalent to material reaching tissues. Particle size alone does not provide a reliable rule for predicting how much will be absorbed.

Research on functionalised nanoparticles often uses controlled coatings and specialised measurement methods. Changes in surface properties, aggregation or formulation can alter biological interactions. Those findings cannot simply be transferred to a homemade dispersion or a poorly characterised consumer product.

What the EFSA assessment of E 175 establishes

In its 2016 re-evaluation of gold as the food additive E 175, the European Food Safety Authority considered the available data insufficient for a full risk assessment and for establishing an acceptable daily intake.

This conclusion concerns the assessed food additive and the available evidence. It is neither proof that every gold product causes harm nor reassurance that colloidal gold can be swallowed safely. A food-additive assessment also does not demonstrate a therapeutic benefit.

Separate uptake from a health benefit

Even if a material is absorbed, that does not show that it improves health. A useful product claim needs evidence of a meaningful outcome as well as information on adverse effects. Retail colloidal gold does not have an established general health benefit or adequately demonstrated long-term safety.

Practical conclusion

The responsible assessment is product-specific: identify the material, its intended use and the relevant evidence. A PPM label, a nanoparticle research paper or the word pure cannot fill gaps in clinical knowledge. Persistent symptoms deserve appropriate assessment rather than an assumption that gold will correct an underlying problem.