Does cocoa naturally have cadmium? A look at soil, sourcing, and health

December 27, 2025 •

4 min read

Cadmium, a naturally occurring heavy metal, can be found in the Earth's crust, especially in volcanic and sedimentary soils. Because of this, it is true that cocoa trees, which absorb minerals from the soil, will also naturally have cadmium present in their beans.

Quick Summary

Cadmium is naturally absorbed by cocoa plants from the soil, with concentrations varying by geography. Dark chocolate and cocoa powder often have higher levels due to greater cocoa solids. Mitigation efforts focus on soil management and sourcing.

Key Points

Natural Origin: Cadmium is absorbed by cocoa plants from the soil, especially in regions with volcanic and mineral-rich earth, making its presence natural.
Regional Differences: Cocoa from Latin American countries like Peru and Ecuador often has higher cadmium levels than that from West Africa due to soil composition.
Concentration and Dilution: Dark chocolate and cocoa powder, with more cocoa solids, contain higher concentrations of cadmium compared to milk chocolate, where the cadmium is diluted by milk and sugar.
Active Mitigation: The industry uses several techniques, including soil amendment with lime, post-harvest blending, and genetic selection of low-cadmium varieties, to minimize levels.
Regulation Exists: Regulatory bodies, such as the European Union and Codex Alimentarius Commission, have set maximum permissible cadmium levels for cocoa products to protect consumer health.
Safe in Moderation: While high, prolonged exposure can be harmful, consuming high-quality chocolate in moderation as part of a balanced diet poses a very low risk for most people.

The Natural Origin of Cadmium in Cocoa

Cadmium is a heavy metal that is a natural component of certain soils, primarily those formed by volcanic activity or containing high mineral deposits. While the presence of cadmium in food products can be concerning, it is not a recent phenomenon. Cacao trees, like many other plants, absorb minerals and elements from the soil through their root systems. This means that the amount of cadmium a cocoa bean contains is directly linked to the cadmium content of the soil where the tree grew. Unlike lead, which can contaminate beans after harvest, cadmium is already present inside the beans before they are picked. This geogenic (natural) source is a primary reason why some cocoa is more affected than others, but human activities also play a role.

Factors Influencing Cadmium Levels

Several factors influence how much cadmium ends up in the cocoa bean:

Geographic Origin: This is one of the most significant factors. Cocoa from Latin American countries, like Peru, Ecuador, and Colombia, often has higher cadmium levels due to their young, volcanic soils. In contrast, cocoa from West Africa tends to have lower levels.
Soil pH: Cadmium is more available for plant uptake in acidic soils (pH ≤ 6.5). Farmers can mitigate this by raising the soil's pH with lime, though this practice has limitations.
Soil Organic Matter: Soils with higher organic matter content tend to bind more cadmium, making it less available for absorption by the plant's roots.
Genetic Variation: Different cacao genotypes (cultivars) have varying capacities for absorbing and translocating cadmium to their beans. Research is underway to identify and breed varieties that naturally accumulate less cadmium.

The Role of Processing

How cocoa is processed into chocolate also affects the final cadmium concentration. The heavy metal is concentrated in the cocoa solids, not the fat (cocoa butter). This has important implications for different types of chocolate products.

Concentration: Since cadmium binds to cocoa solids, products with a higher percentage of cocoa, such as dark chocolate and cocoa powder, will have a higher concentration of cadmium per kilogram.
Dilution: Milk chocolate, which contains significant amounts of sugar and milk, has a lower concentration of cocoa solids and thus a diluted cadmium level.
Fermentation: Recent research has explored using controlled fermentation to reduce cadmium levels in the bean's nibs by prompting the cadmium to migrate to the outer tissues (testa), which are removed during processing.

Cadmium Concentration by Product Type


Product Type	Cocoa Solids Content	Relative Cadmium Level	Rationale
Cocoa Powder	Very High (Often >90%)	Highest	Cadmium remains in the solids after the pressing process removes cocoa butter.
Dark Chocolate	High (Often >50%)	High	Contains a large percentage of cocoa mass, concentrating the heavy metal.
Milk Chocolate	Lower (Often <50%)	Lower	Cadmium is diluted by the addition of milk and sugar, which contain no cocoa solids.
Cocoa Butter	None	Extremely Low	The fat pressed from the bean, which carries virtually no cadmium.

Mitigation and Regulation

To address the issue, the cocoa industry and regulatory bodies are implementing and researching various mitigation strategies. These efforts range from farm-level agronomic practices to advanced genetic research.

Agronomic Management: Farmers can amend the soil by adding lime to increase the pH and make cadmium less soluble and available for plant uptake. However, this is only effective in the topsoil, and deeper roots can still absorb cadmium.
Genetic Selection: Scientists are evaluating existing and developing new cacao genotypes that are low-cadmium accumulators, focusing on varieties with higher resilience to uptake.
Post-Harvest Practices: Techniques like blending beans from high-cadmium regions with those from low-cadmium regions can help bring the overall cadmium concentration of the final product within safe limits. Improving fermentation and drying procedures can also play a role.
Regulations and Testing: Regulatory bodies like the European Union and the Codex Alimentarius Commission have set maximum permissible levels for cadmium in chocolate and cocoa products. These regulations incentivize manufacturers to carefully source and test their beans, ensuring consumer safety. The state of California also has specific regulations under Proposition 65.

For more detailed information on international food safety standards, you can refer to the FAO Codex Alimentarius Commission's guidelines regarding contaminants.

Conclusion

In summary, it is a fact that cadmium is naturally present in cocoa beans, originating primarily from the soil where cacao trees grow. The concentration can vary significantly based on geographic location, soil chemistry, and the specific variety of cacao tree. While this presents a challenge, it's not a cause for alarm, as the industry has been aware of this for decades and has developed multiple strategies to manage and reduce cadmium levels in the final products. Consumers can make informed choices by understanding that dark chocolate and cocoa powder generally contain more cadmium than milk chocolate and that responsible manufacturers test their products to ensure they meet strict international safety standards. By continuing to innovate in soil management, genetics, and processing, the industry can ensure we all continue to enjoy cocoa safely for years to come.

Frequently Asked Questions

While industrial pollution can contribute, the primary source of cadmium in cocoa is geogenic, meaning it occurs naturally in certain types of soil, especially volcanic soils.

Most, if not all, cocoa grown will contain some level of cadmium, as the plant absorbs it from the soil. The amount varies widely depending on the region and growing conditions.

Cadmium binds to the cocoa solids. Dark chocolate contains a much higher percentage of these solids compared to milk chocolate, where the cadmium content is diluted by other ingredients like milk and sugar.

Consistent, long-term exposure to high doses of heavy metals like cadmium can pose health risks, particularly affecting the kidneys. However, regulatory standards ensure that most consumer products are safe when consumed in moderation.

Farmers and researchers are employing strategies like amending soil with lime to raise pH, selecting low-cadmium accumulating tree varieties, and refining post-harvest processing methods.

You can reduce your intake by moderating consumption of high-cocoa products like dark chocolate and cocoa powder. Choosing products from regions known for lower cadmium soil, such as West Africa, can also help.

Yes, some studies suggest that optimizing the fermentation process can help mobilize cadmium from the cocoa bean nibs to the outer shell (testa), which is later discarded. However, this depends on careful process control.