What Food Has the Most Cadmium and How to Limit Exposure

November 18, 2025 •

4 min read

According to the European Commission, major dietary sources of cadmium exposure include cereals, vegetables, and shellfish. While many foods contain trace amounts of this heavy metal, understanding which food has the most cadmium by concentration is key to managing your intake.

Quick Summary

This article examines which foods contain the highest concentrations of cadmium, such as organ meats and shellfish, and identifies other significant dietary contributors like grains and leafy vegetables. It also provides strategies for reducing overall cadmium exposure through your diet.

Key Points

High-Concentration Foods: Organ meats like kidney and liver, and certain shellfish such as oysters, contain the highest cadmium concentrations per unit of weight.
Major Dietary Contributors: Staple foods like cereals, grains, leafy greens, and root vegetables contribute most to a person's overall cadmium intake due to higher consumption volume.
Source of Contamination: Cadmium primarily enters the food chain through agricultural soil, often as a result of industrial pollution or fertilizers.
Accumulation: Cadmium accumulates in the body over time, with the kidneys being the primary storage site.
Mitigation Strategy: The most effective way to manage cadmium exposure is to eat a varied diet, ensuring you do not over-rely on a single food source.
Protecting Yourself: Maintaining sufficient iron and calcium levels in your diet can help reduce the body's absorption of cadmium.
Avoid Smoking: For smokers, tobacco is a more significant source of cadmium exposure than diet.

Understanding How Cadmium Enters the Food Supply

Cadmium is a naturally occurring heavy metal that also enters the environment through human activities like industrial pollution and agricultural practices, such as the use of phosphate fertilizers. From the soil, plants can absorb cadmium through their roots. For animals, exposure can occur by eating contaminated plants. For humans, diet is the primary source of cadmium exposure, especially for non-smokers. Once ingested, cadmium can accumulate in the body, primarily in the kidneys, over a long period.

Foods with the Highest Cadmium Concentration

When examining the cadmium content per unit of weight, some foods stand out for their particularly high concentrations. These include:

Organ Meats

Animal organs like kidney and liver are consistently reported to contain some of the highest cadmium concentrations. This is because cadmium accumulates in these filtration organs over the animal's lifetime. For instance, studies have shown remarkably high cadmium levels in pig kidneys and livers. Given the bioaccumulation, frequent consumption of offal can significantly increase a person's dietary exposure.

Shellfish and Crustaceans

Certain aquatic creatures, particularly bottom-feeders, accumulate heavy metals from the water and sediment in which they live. Bivalve molluscs, such as oysters and mussels, as well as crustaceans like crab and lobster, are known to contain elevated levels of cadmium. A study in Thailand found high levels in blood cockles. While the bioavailability of cadmium from shellfish may be lower than from other sources, according to some experts, their high concentration remains a factor.

Edible Fungi and Algae

Research in China has identified edible fungi and algae as having some of the highest average cadmium concentrations among all food types analyzed. Mushrooms, especially wild varieties, are noted for their ability to accumulate cadmium. This is attributed to their extensive mycelial network, which enhances absorption from the soil.

Major Contributors to Overall Dietary Cadmium

While the foods above may have the highest concentrations per serving, other foods contribute more to the average person's total cadmium intake simply because they are consumed far more frequently and in larger quantities. These include:

Grains and Cereal Products

Staple foods such as cereals, bread, pasta, and rice are major dietary contributors to cadmium exposure for most populations. For example, in the US, cereals and bread accounted for 34% of total cadmium intake in one study. This is less about high concentration in a single serving and more about the cumulative effect of frequent consumption. Rice, especially in certain geographical areas, can also be a major source due to soil contamination.

Leafy Green and Root Vegetables

Vegetables that are efficient at absorbing cadmium from the soil can contribute significantly to dietary intake. Leafy greens like spinach, kale, and lettuce are notable accumulators, as are root vegetables like potatoes, carrots, and sweet potatoes. An FDA study found mean concentrations of raw spinach to be particularly high. A varied diet is recommended to avoid over-reliance on any single high-absorbing vegetable.

Nuts and Seeds

Some nuts and seeds can also be significant sources of cadmium. Sunflower seeds, in particular, have been found to contain high concentrations. Peanuts and certain other nuts can also contain elevated levels, as shown in studies of European markets.

Concentration vs. Contribution: A Comparative Look


Food Category	Cadmium Concentration (µg/kg)	Contribution to Overall Intake	Notes
Organ Meats	Very High (e.g., >50,000)*	Low-Moderate	High concentration, but low consumption for most people.
Bivalve Shellfish	Very High (e.g., >1,000)*	Low-Moderate	High concentration, but low consumption and potentially low bioavailability.
Edible Fungi/Algae	High (e.g., >300)*	Low	Significant accumulator, but not a dietary staple for most.
Sunflower Seeds	High (333)*	Low-Moderate	Can contribute noticeably depending on consumption levels.
Leafy Greens (Spinach)	Moderate-High (up to 400)*	High	Regularly consumed staple that accumulates cadmium.
Cereals/Grains	Lower per serving	Highest	Low concentration per serving, but a major dietary source due to consumption volume.
Potatoes	Lower per serving	Moderate-High	Regularly consumed root vegetable that can accumulate cadmium.

*Concentration values vary widely based on soil, region, and pollution levels. Values shown are illustrative examples from research studies.

Reducing Your Exposure to Cadmium

While it is impossible to eliminate cadmium completely, a few strategies can help mitigate exposure:

Eat a varied diet: Diversifying your food choices across different food groups is the most effective strategy. This prevents overconsumption of any single food that might contain higher levels of cadmium.
Maintain adequate iron and calcium levels: Studies suggest that deficiencies in these minerals can lead to higher absorption of cadmium by the body. A balanced diet rich in iron and calcium can offer protection.
Know your sources: If you regularly consume specific high-concentration foods like offal or shellfish, practice moderation. If you are concerned about contamination in staples like rice, consider varying your grain intake.
Avoid smoking: Tobacco smoke is a significant source of cadmium exposure, often surpassing dietary sources for smokers.

Conclusion

Identifying what food has the most cadmium reveals a distinction between foods with high concentration per serving and those that contribute the most to overall dietary intake due to consumption volume. Organ meats and certain shellfish often hold the highest concentrations, while staple foods like cereals and leafy greens contribute the most to an average person's total exposure. By eating a diverse diet and maintaining good nutrition, individuals can effectively manage their exposure to dietary cadmium.

For more detailed information on contaminants in food, consult the FDA's official resources.

Frequently Asked Questions

Cadmium is a naturally occurring heavy metal and environmental pollutant. It is a concern because chronic, low-level exposure primarily through diet can accumulate in the kidneys and lead to kidney damage and other health issues over time.

No, not all leafy greens contain high levels, but certain varieties like spinach and lettuce are known accumulators. The cadmium content is largely dependent on the soil composition where the vegetable was grown.

Cereals and grains absorb cadmium from the soil during growth, with factors like soil pH and contaminants influencing uptake. While the concentration per serving may be low, their high rate of consumption makes them a major contributor to overall dietary exposure.

Organ meats have a very high concentration of cadmium, so it is best to consume them in moderation. For most people, infrequent consumption poses a minimal risk, but regular intake could contribute to higher exposure.

Yes, some dark chocolate and cocoa products have been found to contain cadmium. Levels can vary by brand and origin. While typically not a primary source of exposure, regular, heavy consumption should be considered in the context of overall intake.

Yes, studies have found that adequate levels of certain minerals, particularly iron and calcium, can help protect the body from absorbing cadmium. Maintaining a balanced diet rich in these nutrients is a protective measure.

The most important action is to eat a varied and diverse diet. Relying too heavily on a single food group or product can increase your risk, so rotating your food choices is key to minimizing exposure.