Cacao trees are very good at pulling minerals out of soil. That is part of why cacao is rich in magnesium and iron. It is also why cocoa products keep showing up in heavy metal testing with lead and cadmium levels that make headlines. Here is what the testing actually found, where the metals come from, and what we do about it.
What the testing found
Consumer Reports, December 2022. CR tested 28 dark chocolate bars from 21 brands for lead and cadmium. Every bar had measurable amounts of both. Twenty-three of the 28 exceeded California's Proposition 65 maximum allowable dose level for at least one metal in a single one-ounce serving. Those Prop 65 thresholds are 0.5 micrograms per day for lead and 4.1 micrograms per day for cadmium.
George Washington University, July 2024. Researchers published a multi-year analysis of 72 dark chocolate and cocoa products bought in the US between 2014 and 2022 in Frontiers in Nutrition. Forty-three percent exceeded the Prop 65 level for lead, and 35 percent exceeded it for cadmium. One detail surprised a lot of people: products labeled organic tested higher for both metals than non-organic products, not lower.
Two things worth saying honestly. Prop 65 levels are deliberately conservative; they are set far below the levels where harm has been documented, and a bar that exceeds them is not a poisoning. And the industry's response, that these metals are naturally present in cacao and levels have been falling, is also true. But "naturally present" is not the same as "unavoidable," and the range between brands is enormous. That range is the whole point.
Where lead and cadmium come from (they are different)
Cadmium gets into the bean while it is growing. Cacao roots take it up from soil, and some soils, especially volcanic and certain South American soils, carry more of it. Cadmium is inside the bean, so it cannot be washed off. It varies by origin, by farm, and even by harvest.
Lead is mostly a post-harvest problem. Fresh beans have very little of it. Lead accumulates during fermentation and drying, when beans sit outdoors on the ground or on tarps and pick up lead-bearing dust and soil. Drying beans on raised beds, away from roads, and washing them changes the number dramatically. In other words, lead is largely a handling decision, not a fate.
The practical consequence: a brand cannot promise low metals by picking a fancy origin. It has to test the batch it is actually selling you.
What "tested for heavy metals" should mean
A lot of labels say "third-party tested." Ask three questions:
- Tested per batch, or once? Cadmium changes with every harvest. A test from two years ago describes a different bag of beans.
- Which metals? The full panel is lead, cadmium, arsenic, and mercury. Lead and cadmium are the ones that matter most in cacao, but a serious lab report shows all four.
- Can you see the numbers? "Tested" without results is a vibe. A certificate of analysis with micrograms per serving is data.
What we do
Every batch of Actual Superfoods cacao is tested by an independent lab for lead, cadmium, arsenic, and mercury before it goes into a tin. The batch number is printed on the base of every tin, and the per-batch results are published on our lab results page as each batch is released. If you want the current certificate directly, email support@actualsuperfoods.shop and we will send it.
We do this because the cacao category has a real problem, and the only credible answer is receipts. It costs money, it slows down production when a batch fails, and it is the reason we can put "heavy-metal tested" on the front of the tin without flinching.
Should you stop eating chocolate?
No. The dose makes the difference, and a daily serving of a tested, low-metal cacao is a very different thing from a daily bar of untested dark chocolate. If you are pregnant, feeding small children, or eating cacao every single day, it is reasonable to insist on batch results. That is what we would do. It is what we did.
Sources
- Consumer Reports. "Lead and Cadmium Could Be in Your Dark Chocolate." December 2022.
- Hands JM et al. "A multi-year heavy metal analysis of 72 dark chocolate and cocoa products in the USA." Frontiers in Nutrition, July 31, 2024.
- California OEHHA, Proposition 65 Maximum Allowable Dose Levels for lead (0.5 mcg/day) and cadmium (4.1 mcg/day).