What you need to know and how to detox
This is the kind of health news nightmares are made of. Like a lot of you, I am a ‘snack on a few pieces of an organic dark chocolate bar for dessert’ kind of girl. I typically recommend dark chocolate for magnesium, brain health, heart health, mood support, and other benefits! So, with the recent news about dark chocolate containing dangerous levels of heavy metal, I was heartbroken. Have all the extra squares eaten with antioxidant-rich promises caused more harm than good?
A 2022 Consumer Report tested both well-known and niche chocolate brands and found that 23 of them contained heavy metal levels above the allowed amounts by the most protective standard, and could thus be considered dangerous to health. There are no federal limits on cacao and heavy metals, so California’s trusted Maximum Allowable Dose methodology was used. Consistent, long-term exposure to even small amounts of heavy metals can lead to a variety of health problems, discussed more in-depth below.
This being said, I want to let you know that THERE IS HOPE! Keep reading for the latest research on how dark chocolate is made, why the process can cause exposure to heavy metals, the health problems caused by the heavy metals: lead and cadmium, and how to choose a dark chocolate that doesn’t contain heavy metals.
HOW DARK CHOCOLATE IS PROCESSED
Ripened pods from the Theobroma Cacao plants are harvested and then go into a natural fermentation phase. Cacao beans are then separated from the pods to ferment. This process takes about seven days. The natural sugars, yeast, and bacteria ferment the beans into a less bitter tasting bean. To prevent mold growth, they have to go into the drying process immediately. Cacao beans are dried in the sun for about a week. After the drying period, the beans are roasted and processed into fine powders, solid pieces, and butter for our enjoyment.
WHY IS THERE LEAD IN DARK CHOCOLATE?
The heavy metal, lead, infiltrates cacao beans as they are drying. Traditionally, fermented cacao beans are dried in the sun for days after being picked, and dust and dirt containing lead layers onto the beans.
California’s Maximum Allowable Dose of lead is 0.5 micrograms. Ingesting high amounts of lead in a short period of time can cause one or more of the following symptoms: headaches, irritability, memory loss, constipation, fatigue, tingling sensations, and loss of appetite. Long-term exposure symptoms become more serious. The CDC states that the symptoms of lead poisoning include anemia, physical weakness, kidney damage, and brain damage. High levels of lead exposure for pregnant women is associated with damage to a fetus’ developing nervous system as well as lower levels of intelligence and behavioral issues. Lead targets neural stem cells and causes long-lasting cognitive dysfunction.
Research shows that lead is most readily absorbed by breathing it in, which happens in situations like the inhalation of fossil fuel combustion products or lead-based paints. Lead is also consumed through water from lead pipes. However, no matter how it ends up in your body, the negative effects are the same. So maybe you’re not eating dark chocolate every day, but the cumulation from other sources may be causing the health issues you’re experiencing.
Lead has been used by humans since prehistoric times, and levels of exposure and absorption have increased widely around the planet. Did you know that lead is absorbed and stored in your tissues, bones, and blood? It is typically cleared slowly from the body, and that rate of clearance slows with age and health decline.
WHY IS THERE CADMIUM IN DARK CHOCOLATE?
The heavy metal, cadmium, was discovered in every one of the 28 brands tested in the study. Cadmium is found heavily in the soil where cacao is grown, and it gets absorbed by the cacao plants because of the acidic pH value of the soil. This is alarming, given that cacao is now the highest, tested dietary source of cadmium, alongside cigarettes.
High levels of cadmium in the body can result in issues such as kidney disease, bone disease, lung-damage, cancer, and more. Cadmium is regarded as a carcinogen by four major US and international health organizations.
Cadmium is referred to as a 20th century metal. Commercial production really began in the 1900’s. However, in the last two decades, over 65% of the total world production has taken place. Cadmium is used for protective plating on steel; stabilizers for PVC pipe production; pigmentation of plastics and glasses; as an electrode material in certain batteries; and as an alloy component. Cadmium gets into the environment through mining and various waste that is contaminated with cadmium, and eventually ends up in the soil via fertilizers and sewage. It is also used as a stabilizer in plastics. The CDC regulates cadmium levels in bottled drinking water to be below 0.005 mg/L.
Specific crops take up more cadmium from the ground than others, including rice, durum wheat, flax, sunflower, and potatoes, cereal grains, barley, and other vegetables. It is possible for these crops to accumulate amounts of cadmium over the proposed acceptable amounts. Latin America was actually found to have higher levels of cadmium in the soil than accepted by the European Union in 2019. The heavy metal is also found in liver and kidney meat. Sea creatures such as shellfish, crustaceans, and fungi naturally accumulate cadmium.
Research on creating low-cultivar crops may help lower cadmium levels in our food supply. There is also a protein called CAL1, that can help rice from accumulating these dangerous metals. In the meantime, sticking to the dark chocolate brands that are deemed safe from consumer reports may be your best bet.
HEAVY METALS AND FERTILITY
There is a strong association between reduced fertility and lead exposure. In 2018 an interesting study from researchers at Carnegie Mellon University showed lowered fertility rates for women between the ages of 15 and 44 correlating with increased lead exposure. For men, it was found in a separate study that exposure to inorganic lead is detrimental to semen quality.
Looking a little farther back, in 1978-88, the Clean Air act regulations reduced airborne lead levels and fertility rates increased. Unfortunately, in the 2000’s higher levels of lead on topsoil decreased fertility rates. These results are thought to be due to the link found between lead exposure and smaller ovaries, lower number of potential eggs, and an increased rate of follicle death.
When it comes to shielding pregnant women (and children) from the harmful effects of lead and cadmium, researchers found a logical connection between detoxifying and protecting the organs and supplementing with zinc, iron, and calcium.
WHAT KIND OF CHOCOLATE IS SAFE?
For the dark chocolate bars tested in the 2022 Consumer Report, it was noted that having a serving once a week was considered minimally harmful. There were also five dark chocolate brands that fully passed the lead and cadmium test, listed here. Additionally, chocolate bars containing less than 65% cacao have less heavy metal concentrations. Thus, milk chocolate could be a safer alternative. Most importantly, do some research on your favorite chocolate brands. Understand the process from the location it was sourced to the minute it reaches your shopping cart. We suggest a healthy and safe hot cocoa recipe that you can try and see the benefits from it.
DETOXING FROM HARMFUL DARK CHOCOLATE METALS
If you choose dark chocolate for the polyphenol content, there are other whole foods you might look to as substitutions. These include grapes, green apples, and green tea.
Certain nutrients (calcium, iron, zinc, selenium, and vitamin C) can also help to detox heavy metals from your bones, tissues, and blood by binding to the metals and removing them through excretion. Because zinc has a similar make up physically and chemically to both cadmium and lead, it competes for the binding sites on protein enzymes, relieves oxidative stress from these specific harmful metals, and also boosts the synthesizing of metallothionein, which binds to cadmium and removes it from the body. Selenium was also shown to fight the oxidative stress from these two heavy metals, enhance the detoxification processes, and protect the brain, lungs, liver, kidneys and blood from toxicity. Having vitamin E in the body before ingesting cadmium was shown to have protective effects as well.
A deficiency in vitamin B, B-6, and vitamin C is linked to worsened symptoms of heavy metal toxicity. Vitamin C’s antioxidant effects are helpful in fighting damage, and it is also a chelating agent with lead, meaning it decreases its levels in the blood. Supplementing with vitamin B-1 was shown to decrease levels of lead in the liver, kidneys, bone and blood.
Add these foods to your diet to help detox the build up of lead and cadmium (aim for organic):
- blueberries (wild is best)
- Atlantic dulse
- broccoli sprouts
- green tea
- leafy greens (like spinach, kale, moringa)
These phytonutrients have also been found to be protective against lead and cadmium:
Sometimes unfortunate realities are revealed, such as the reality that there may be heavy metals in your dark chocolate. However, I’m grateful that the research is being done as evidence to the importance of understanding what’s actually going into your body. Let’s continue to learn and improve our health and our world together.