For the Love of Chocolate. When Organic isn't Actually 'Best'

While there are many health benefits to dark chocolate, most chocolate contains cadmium which is a toxic heavy metal. Outlined below highlights the benefits and the chocolates that should be avoided due to the cadmium content.

With the arrival of holidays and cooler weather, we start to envision chocolate drinks and treats. There are very few things that produce a sense of delight like chocolate.

To paraphrase from Michael Pollen's book, when given the word chocolate cake, Americans said ‘guilt’ but the French replied with ‘celebration’.

While chocolate is a high-calorie sweet it also has some health benefits. Eating a little bit here and there can be a wholesome indulgence. But for many it is addictive and hard to stop eating. This is because chocolate does contain a bit of phenylethylamine (PEA) which is linked to our brain’s pleasure centers and endorphins. PEA also potentiates dopamine, our reward center. Another neurotransmitter, serotonin is increased by cocoa, the primary ingredient in chocolate. Serotonin plays a major role in positive mood and emotional health.

Cocoa, the key ingredient in chocolate contains biologically active phenolic compounds. The higher the cocoa content, as in dark chocolate, the more benefits there are. Dark chocolate may also contain less fat and sugar, but it is important to check the label.

Dark chocolate contains 50-90% cocoa solids, cocoa butter, and sugar, whereas milk chocolate contains anywhere from 10-50% cocoa solids, cocoa butter, milk in some form, and sugar. Lower quality chocolates may also add butter fat, vegetable oils, or artificial colors or flavors.

Health Benefits

Dark chocolate contains up to 2-3 times more flavanol-rich cocoa solids than milk chocolate and the higher the cocoa solids the more antioxidants. Flavanols have been shown to reduce LDL cholesterol, support the production of nitric oxide (NO) in the endolethium (the inner cell lining of blood vessels) that helps to relax the blood vessels and improve blood flow, thereby lowering blood pressure. Flavanols in chocolate can increase insulin sensitivity in short term studies; in the long run this could reduce the risk of diabetes. Additionally, polyphenols inhibit blood platelets from clumping together, reducing the risk of atherosclerosis or hardening of the arteries.

Other observational studies suggest a link between high cocoa or chocolate intake of 6 grams daily (1-2 small squares) and a reduced risk of heart disease and mortality, possibly in part by reducing blood pressure and inflammation.

Choosing dark chocolate and eating modest quantities may offer the greatest health benefits.

Cadmium in Chocolate

But, many dark chocolate products are contaminated with high levels of cadmium which is a toxic heavy metal. Cadmium is an element that is not used by the body and is toxic. It is a probable carcinogen and can be toxic to the kidneys and soften bones. Cadmium is mainly produced as a by production of batteries and accumulates in the air, soil and water. The concentration of cadmium in cocoa is 10-20 times higher than other “high” plant-based foods such as peanuts and sunflower seeds.

The key is finding a chocolate that is high in flavonoids and low in cadmium. Consumer labs is a great testing service that has tested many different brands of chocolate in the amounts of cadmium and flavonoids.

Of interest, the studies by Consumer Labs found that organic products contained more cadmium than non-organic. This may be due to where the cocoa is grown. Chocolate from Central or South America were much higher in cadmium than chocolate from African sources.

See the graph below from Consumer Labs. The red line is the amount of Cadmium and the blue is the amount of flavonoids.

As you can see Montezuma’s Dark Chocolate Absolute Black, had the best ratio of Flavonoids to Cadmium. This product contains 14mg/g of flavanols and just 0.06 mcg of cadmium per/gm of chocolate. Trader Joe's The Dark Chocolate Lover's Chocolate Bar had the highest level of cadmium at 29mcg/gm

All cocoa powders had high concentrations of cadmium except for Ghirardelli Chocolate Premium Baking Powder. Healthworks Cocoa Powder and Hershey’s Cocoa Special Dark had the worst.

If you don’t see a chocolate bar or powder that you use on the chart, find one that sources the cocoa from Africa instead of Central or South America.