Research reveals ways lead and cadmium in chocolate may be reduced | Hacker News Reader

Research reveals ways lead and cadmium in chocolate may be reduced

candyusa.com

121 pointsmaerF0x082 comments

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here's the actual brands and products:

https://www.consumerreports.org/health/food-safety/lead-and-...

or better:

https://www.asyousow.org/environmental-health/toxic-enforcem...

I go through the Equal Exchange 80% dark product about one bar every few weeks so I will be researching cadmium a bit

(later)

So after some research on cadmium and the specific data California has on it (https://oehha.ca.gov/proposition-65/chemicals/cadmium), I think my general take on the Equal Exchange chocolate I eat quite a lot of is that the saturated fat (15g) is still orders of magnitude more dangerous than the cadmium.

Interestingly, the product itself seems much less appealing to me knowing it has this trace level of cadmium that will likely not affect me in any way, vs. the saturated fat that I already knew contributes towards directly life-threatening LDL cholesterol.

Saturated fat increases LDL by increasing the particle size, whereas it seems to be increases in particle number that are associated with increased cardiovascular risk. This is likely why studies fail to find any real world increase in risk, and the saturated fat heart disease theory, while still under debate, is mostly out of favor nowadays.

Yes, saturated fat is unjustly maligned. And from an evolutionary perspective, it doesn't make sense that it would be so harmful; pre-agricultural diets had lots of saturated fat so human metabolisms should have evolved to handle it well.

Also, when our bodies store calories (de novo lipogenesis), other forms of calories are converted to saturated fats. It doesn't make sense that our bodies main calorie store would be basically 'poison.' Is starch poisonous to a potato?

Evolutionary arguments here don't make much sense - the vast majority of human history we had average lifespans on the order of 25 or 30 years. If the negative effects of something (like heart disease) typically fail to manifest within that window there is no selection mechanism by which this kind of eating has an effect on long-term evolution of the species.

As others have mentioned, this is true, but is a great illustration of how averages are extremely misleading when representing non-normally distributed data, and are used excessively in popular culture and media. Modal (most common single digit) lifespan of hunter gatherers is usually in the 70s, despite low averages (mean) due to high infant mortality [1]. Modern health care massively reduced infant mortality, but doesn't change mortality much in middle years, when most people don't actually need any healthcare.

[1] https://link.springer.com/referenceworkentry/10.1007/978-3-3...

You are off by a factor of 2. If you exclude deaths in early childhood people regularly made it to their 60s

But if everyone is done having kids by their mid 30's, the increase in heart disease risk in their 50's still wouldn't show up as an evolutionary pressure. Especially when you consider humans are tribal animals and parental survival is not critical to offspring survival as long as the tribe keeps going.

One interesting hypothesis I've heard is that there is actually a huge selection pressure for long human lifespans, to preserve cultural knowledge and skills necessary for survival, as well as to help with child care. The parenting age adults can't exactly hunt and gather if they have to watch babies all day long- yet human children are pretty helpless and need almost constant care for years.

As a dad, even in modern times I couldn't work at all without someone to help with parenting... however if I can work, I could bring in enough resources to support an entire family.

>The parenting age adults can't exactly hunt and gather if they have to watch babies all day long- yet human children are pretty helpless and need almost constant care for years.

Gathering food or light manual work? You just stick 'em in a papoose (we used a shoulder sling). Heavier work, hang the papoose in a tree. Once they can walk they can gather food and do light work.

I'm not saying grandparents wouldn't make it easier, but babies/toddlers are quite adaptable.

I think for hunting (with weapons) you'd want them to be at least 5.

I would imagine having pepaw & memaw around to watch the kiddos while mom and dad were out gathering food would be a huge boon as far as keeping your progeny alive to reproduce again.

Hmm, good call. Your comment about longer lifespans having an indirect impact on the spread of personal genetic material is also insightful. Glad to be corrected!

I thought that was only true if you included infant deaths. I haven’t researched it but that’s what I as a layman thought.

That's also incomplete knowledge. If you made it to adult hood your chances of living to 50 or 60 are way underestimated by "pop culture ancient humans" knowledge. Kids are kind of weak compared to adults immune system wise (in most cases!).

I've heard that, for the most part, small dense LDL is what is mostly found in cardiovascular disease.

well chocolate is high in calories and much more so when you buy a product that adds a bunch of sugar. this is relevant because people who eat a lot of chocolate have bad health but still probably dont have any lead problems aside from subtle, low dose related ones, which will be hard to distinguish from having unhealthy calory intake

Most "chocolate" products really have little, if any chocolate. Google says Hershey's milk chocolate is only 11% actual cacao. Still, plenty of people eat 85-100% cacao dark chocolate, or even savory chocolate foods like Mole in Mexican food, which I think should be considered separately from, e.g. chocolate flavored candy. Interestingly, cacao is one of the best dietary sources of copper, and it seems plausible that getting more copper this way would overall reduce risk of cardiovascular disease [1-3].

  [1] https://perfecthealthdiet.com/2012/11/chocolate-what-is-the-optimal-dose/ 
  [2] https://perfecthealthdiet.com/recommended-supplements/
  [3] https://newsinfo.inquirer.net/204871/dark-chocolate-cuts-heart-deaths-australian-study

you get enough copper (to meet national recommendations) just by eating anything, no need to seek it out.

what i want to know is how to correctly interpret all these studies that claim some food substantially increases health outlooks.

while those are spam websites (buy this, buy that, amazonamazonamazonamazonamazon), its still possible for them to be correct

If you follow those links deeper, there is substantial reduction in cardiovascular disease risk with higher copper intake from supplementation, if it is balanced with zinc intake. National recommendations just prevent acute deficiency symptoms and don't address chronic illness risk.

The perfect health diet website isn't trying to sell you supplements but just make it easier to find what they buy for themselves personally, it's a orphaned health blog by a scientist couple I know personally that make their money elsewhere as researchers- they haven't even updated the blog in ~4 years. They wrote a very detailed nutrition book where they evaluate the risk/benefits of each common nutrient backed up by a deep literature review- basically redoing what the FDA did for the recommendations you cite, but with newer data. The other one is just a pop news summary of an actual journal article.

You might want to look up more recent research on saturated fat. there's still no doubt that hydrolyzed fats are horrible for you though.

my cholesterol goes up proportionally to saturated fat intake, the link between saturated fat and LDL cholesterol (and LDL cholesterol and heart disease) is quite clear despite a huge desire from the public for there to be other "studies" that somehow make it OK to down any amount of dairy. I spent many years hoping for such studies all the while my 300-level cholesterol was lining my arteries with plaque until I finally had to get on statins (not a vegan here).

I guess if it's anecdote vs anecdote, then my cholesterol numbers were bad, as well as other indicators for prediabetes until I switched to a keto diet and dropped 60lbs. Now everything is perfectly normal in my labs and pretty much only watch hydrolyzed/trans fats in my diet, which has moved from keto to "lower carb" and not as strict as strict keto. Saturated fats are fine for me. So, congrats on your health and on mine.

I could have just become vegan which for me would have been easier than keto. I reduced carbs enough to lose 15 pounds (I am only 165) and the numbers didn't budge at all, so that wasn't going to work. Living under a keto regime is not realistic for me.

Great thanks for the link, I wonder if it would be possible to filter by provenance. I imagine some places produce cacao containing more Cd and Pb than other places?

What actual dose are we talking about?

Like, if I'm an average chocolate eater, what proportion of my total lead intake will come from chocolate, vs other sources?

If it's under 0.1%, it isn't worth talking about. If it's 1%, it's worth a passing thought. If it's 10% it's worth some effort to avoid/fix. If it's 50%, I'd probably give up chocolate.

I once read something and I don't remember if it was from a good source. It said that one of the ways they can identify bones from the last 100 year is that older bones have something like 400x less lead traces in them. Basically everyone alive has a degree of lead poisoning thanks to leaded gasoline.

if you take the product they tested with the highest lead concentration (2.4µg per serving), and ate 10 servings, you would have 1/20th of the harmful concentration of lead, according to my calculations: https://news.ycombinator.com/item?id=34018344

It's cumulative, so you can't just take spot concentrations.

How could one test for heavy metals in foods at home? Supposedly Indian spices and other plant products coming from there contain non-trivial amounts of lead [0] [1].

[0] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5415259/

[1] https://www.consumerlab.com/reviews/psyllium-supplements/psy...

First you need to burn the food product for a while to make sure that most of what is left is heavy metals in the ashes. (you typically need a flask for that, and an apparatus to get all the fumes from the burning process safely out).

then from the ashes you need to dissolve them in water (easier said that done), and use reagents based on the type of metal you want to detect from the sample (titration). If you measure accurately the volume of water used to dissolve and the amount of ashes coming from the food product, you can determine a concentration for a specific heavy metal.

Sigma-Aldritch probably sells the reagents you need for heavy metal testing.

Many spices apparently have high levels of heavy metals, I don't know that it's specific to India. There was a study, I think maybe on HN, where they analyzed a bunch of grocery store spice brands and found heavy metals in many.

I know it's not helpful but i get the impression it's not something easy to analyze at home.

With all this stuff (mercury in salmon, toxins in liver, radioactive potassium in bananas), my take is that too much of anything is probably bad an everything is probably fine as part of a varied diet

Consumer Reports did a widely reported survey last year but it was almost random which spice would be contaminated - one source of herb x would be fine but from a different source it was contaminated. https://www.consumerreports.org/food-safety/your-herbs-and-s... Spices that are colored (i.e. turmeric) are particularly vulnerable. https://pubs.acs.org/doi/full/10.1021/acs.est.9b00744

At least with spices you also need very little, so exposure to heavy metal contaminants through that route would be relatively lower.

An XRF spectrometer might work on food.

Looks like chocolate is a known source of heavy metals. Here's just one study I found in Google Scholar:

https://www.sciencedirect.com/science/article/abs/pii/S08891...

So the raw beans have heavy metals? Or does the processing introduce them?

From the OP article, some metals are exclusively from the beans (cadmium), others are introduced later (lead).

But yeah, every time you're eating plant material, there will be some trace level of heavy metal. And it just increases up the food chain.

Bioaccumulation is pretty cool as a phenomenon

The article says that cadmium is in the beans (because it is in the soil). But lead is likely introduced in processing.

I swear this site will make you a nervous wreck about eating or bringing anything into your home if you took it too seriously.

I’ve had to throw out all my non stick pans and plastic containers, stop eating sea food, avoiding seed oils, and now chocolate??

I try not to stress too much. One has to die of something after all.

Cad(mium )buri(ed in it)

Avoidance seems increasingly difficult. Mercury, lead, microplastics, herbicide, whatever. We're living in the toxic soup.

I hope someone(s) are working on detox solutions. Hopefully safer than the current chelation therapies used for life threatening cases.

Interesting that two different Lindt bars fall into different categories. Do they really use different beans for those? It feels like a sampling effect.

Right, I get the impression that their sample sizes were very small.

And that's in the food supply which is supposedly regulation and monitored (not).

You should see what they ALWAYS find in supplements which are not at all regulated and definitely not monitored no matter what anyone thinks or claims.

https://www.consumerreports.org/food-safety/your-herbs-and-s...

Those are spices but it's in every vitamin, mineral, etc. supplement you've ever taken. There are allowed limits but they blow right through them because there's no testing and no oversight and no penalty for doing so.

And yes lead is a forever chemical and yes it is making everyone stupid, this is well proven science beyond all argument, average IQ went way up when leaded car gas was finally banned but lead still sprayed everywhere around airports from aviation fuel.

Directly related and possibly of interest, the 381-page "As You Sow" report "Expert Investigation Related to Cocoa and Chocolate Products" [0] that "Details Simple, Safe, and Low-Cost Solutions to Reduce Levels of Lead and Cadmium in Chocolate" Requires an email address to download though.

[0]: https://www.asyousow.org/blog/2022/8/17/new-report-explains-...

One thing that's apparent from that report is the year effect. Older, pre-2022 tests were much more likely to have very low levels of heavy metals; more recent, 2022 tests are more likely to have high levels. This is true within brand as well. At least it strongly looked that way with many of the brands I saw.

I don't know if that's due to testing effects, or agricultural or processing changes, or shifts in regional supply (maybe due to the pandemic?), or something else. But some of those results make it look like it's a relatively recent, and sharply growing problem.

I find it hard to believe that much lead sticks to the sticky coco beans while they're being dried just out in the open air.

I go outside too - is the same amount of lead sticking to me and my lungs?

Either we're talking super low lead levels here, or it's something else about the processing that causes this - like for example the fleet of leaded fuel powered tools being used to cut the beans down.

Many countries permitted leaded gasoline for a long time, and many of the countries that kept it around the longest are also places that grow a lot of chocolate. Lead from car exhaust tends to stick around in the environment for a long time - as part of the soil and the dust in the air.

In South America [1]:

> The first country in South America initiating the phase-out of leaded gasoline was Brazil, moving toward alcohol fuels and unleaded gasoline from AD 1975 on, and achieving a total phase-out in 1991. On the contrary, unleaded gasoline in Bolivia, Chile, and Peru was not introduced before AD 1990–1991, and leaded gasoline was still in use until 1995 (Bolivia), 2004 (Peru), and 2005 (Chile).

In Africa [2]:

> But lead was still common in fuel in Africa and the Middle East. In 2002, UNEP organized a coalition of African governments and oil companies to promote the phaseout of leaded gas, the supposed vehicular benefits of which have been found to apply only to very old cars driven in extreme conditions. Lead was history in sub-Saharan Africa by 2006, and by 2014 was found only in Algeria, Iraq, Yemen, Myanmar, North Korea, and Afghanistan.

[1] - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4643815/ [2] - https://qz.com/africa/2053227/leaded-gasoline-is-now-banned-...

> Many countries permitted leaded gasoline

Avgas is still leaded in the US.

And if I were the president, I would ban avgas tomorrow.

The planes can all stay grounded till a replacement is available. The damage caused far outweighs the benefits of using it.

Yes, I know ambulance planes probably use it... Yes I know farmers use it for crop dusting. Yes I know some remote alaskan communities rely on flights for supplies. But spreading lead dust throughout the whole nation is worse than not having those things.

> Yes I know farmers use it for crop dusting.

In this context that takes on a very different meaning. I wonder how much lead is directly from crop dusting. Avgas is ~1g/liter of lead and 100LL is 0.5g/liter. A small plane burns ~50 liters per hour.

Are the beans cut down with chainsaws? very confused

Chopped open with machete usually. It's a rather delicate process, as you must chop through the outer shell, but not into the beans, as it would make them extremely bitter.

Cannabis has this problem as well, processing it with certain types of stainless steel can cause chromium to be absorbed into the cannabis.

Source: https://www.analyticalcannabis.com/articles/what-the-cannabi...

Well shoot, now I'm concerned. Me and my pregnant wife both drink Crio Bru[1] which is roasted, ground 100% cacao and brewed similar to coffee. This has me thinking twice about it. It sounds like heavy metals may be present in this stuff too

[1]: https://criobru.com/

If you're brewing it in a drip coffee maker, the paper filter should filter out the majority of the lead.

That is incredibly wrong and dangerous advice. There were studies that showed coffee grounds could be used to filter substantial but not all lead, is that what you misremembered?

I was remembering this: https://www.wired.com/2000/02/coffee-is-your-friend/

"A group of international scientists found that coffee filters can remove from 78 to 90 percent of dissolved heavy metals such as lead and copper from tap water."

It looks like the quote is incorrect though, and it is actually the the ground coffee and not the paper filter that's removing the lead.

Regardless, brewing ground cacao in the same way would likely also filter out some of the lead by the same mechanism, even if not as much. (Since the source of lead is embedded throughout the ground beans, rather than coming from the water which enters at the top of the column.)

Paper coffee filters do not effectively remove lead. Distillation and reverse osmosis remove lead.

You shouldn't say things confidently that you don't know anything about, someone might believe you.

Via news article : https://www.cbsnews.com/news/dark-chocolate-metals-lead-cons...

We must go deeper: https://www.consumerreports.org/health/food-safety/lead-and-...

This source article contains the key information that the heavy metals are not contaminants introduced by the processors, they are present in the beans.

> metals are not contaminants introduced by the processors, they are present in the beans.

That’s true of the cadmium, but not the lead:

> … [L]ead seems to get into cacao after beans are harvested. The researchers found that the metal was typically on the outer shell of the cocoa bean, not in the bean itself. Moreover, lead levels were low soon after beans were picked and removed from pods but increased as beans dried in the sun for days. During that time, lead-filled dust and dirt accumulated on the beans. “We collected beans on the ground that were heavily loaded with lead on the outer shell,” DiBartolomeis says.

That's what I was expecting.

Calling out for botanists to weigh in here - is there something that makes chocolate uniquely susceptible to this and if so, is it part of a class of other plants we typically eat? And lastly, this is for food chemists, is there a reliable way to remove such things in the manufacturing that can be added?

Cacao grows in rainforests, so perhaps they’re adapted to rich soils that over time have become net accumulators of heavy metals.

There’s examples of other plants that thrive in the presence of heavy metals, such as this one that “bleeds” nickel rich sap:

https://www.bbc.com/news/science-environment-45398434.amp

Ah, so Tiberium is technically possible...

Bioaccumulation? It does happen with heavy metals and plants.

Soil quality is the next question.

https://en.wikipedia.org/wiki/Bioaccumulation

https://www.tandfonline.com/doi/full/10.1080/026520305003875...

Not a botanist, but this is not unique to cocoa. Rice, for example, is known to take up arsenic, cadmium, and other nasties from soils. But it varies significantly depending on the rice variety and where it is gown. Basmati rice grown in California, Pakistan, and India is known to have low levels of arsenic compared to most other types of rice.

Your second question is answered in the article:

> For lead, that will mean changes in harvesting and manufacturing practices, says Danielle Fugere, president of As You Sow. Such practices could include minimizing soil contact with beans as they lie in the sun, and drying beans on tables or clean tarps away from roads or with protective covers, so lead-contaminated dust won’t land on them. Another option is finding ways to remove metal contaminants when beans are cleaned at factories, Fugere says.

> Solving for cadmium is trickier, though it is possible, DiBartolomeis says. Carefully breeding or genetically engineering plants to take up less of the heavy metal could help, though that could take several years. Other potential options include replacing older cacao trees with younger ones, because cadmium levels tend to increase as the plants get older, and removing or treating soil known to be contaminated with cadmium.

Generally plants are excellent at removing metals from the environment and concentrating them in different tissues, depending on the species and metal. Poplar trees, for example, have often been used for remediation of Mercury contamination of souls

Not sure about the specifics of cocoa, but not beyond the pale to see cadmium, for example, be concentrated in the beans.

As for removal from food stuffs, it really depends on how the metals are bound to the plant material. Could be as simple as heating up in a vat with agitation, to requiring something so drastic it changes the nature of the chocolate.

Best way is to reduce the amount that can be integrated by the plant, but good luck with that. The farmers would probably have to import heavy-metals reduced soil

Link for Europeans: https://12ft.io/proxy?q=https%3A%2F%2Fwww.consumerreports.or...

The referenced study treats dark chocolate but, since cacao is cacao, wouldn't milk chocolate confected from these beans also have commensurately elevated levels of cadmium and lead?

And, if so, shouldn't this extrapolation be communicated to consumers?

Milk chocolate contains significantly less cacao than dark chocolate. Typically 20-25% cocoa solids, where as dark chocolate is in the 50-90% range. So it should have proportionately less cadmium etc per unit of weight.

As someone who eats about 1-2oz of dark chocolate (usually 85%) per day, this is concerning. However I have found the dark chocolate to be a great stimulant, giving me motivation without anxiety the way caffeine does. Now I’m unsure what to do.

Supposedly the stimulating effect of chocolate mostly comes from PEA (Phenylethylamine) which people just buy in pills to use as a nootropic. So you can just try that if it's only about the effect. Though you'd likely need maois and maybe something else to better recreate what you get from chocolate.

You could try caffeine with L-Theanine supplements. Though I guess those could have lead too. The site I get mine from (bulk supplements) does have a lead warning when you buy, but as I understand it, they do that because lead testing is so expensive its easier to just put up the warning (which they need to be able to sell in California). Of course it could also be laden with lead for all I know. You can get L-Theanine from lots of places though and its most true teas (black, green, white, matcha, etc).

Some brands source their cacao from less contaminated areas: https://www.consumerlab.com/news/best-dark-chocolate-and-coc...

initially this article read as a scam (lobbying corpo "non profit" that claims to care about health and enviro but just creates a worse net effect by wasting resources) and a bit of research concludes:

CDC says [1]:

> Until 2012, children were identified as having a blood lead “level of concern” if the test result was 10 or more micrograms per deciliter (µg/dL) of lead in blood.

the lobbying corpo's very own charts [2] show no lead concentration higher than 2.4µg per serving in any tested product. if you ate a serving of chocolate that contains 2.4µg of lead, you would have no more than 2.4µg/dL of lead, which is lower than the CDC's previously stated harmful level. if the lead was diluted through all the blood in your body (~5L = 50dL), your blood level of lead would be 2.4µg/50dL = 0.048µg/dL, far below the CDC's previously stated harmful level of 10µg/dL. with 10 servings, at which point you will have other issues, you will have 0.48µg/dL, still 1/20th of the harmful level.

1. https://www.cdc.gov/nceh/lead/data/blood-lead-reference-valu...

2. https://www.asyousow.org/environmental-health/toxic-enforcem...

disclaimer: i cant do science or math, maybe i calculated something wrong

I am yet to discover anything healthy produced at large-scale by profit earning companies.

Explains why only crazies like dark chocolate /s

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