By Dr. Mercola
Chocolate is a favorite treat for many people, and it can even be healthy if you choose high-quality dark chocolate that's rich in antioxidants and low in sugar.
Your chocolate treat may be exposing you to an undesirable ingredient, however, as a California-based consumer advocacy group has detected lead in some chocolate brands.
The group, As You Sow, tested 50 cocoa products. More than half contained lead and cadmium levels above California's state limit (cadmium is a metal with dangerous properties similar to lead).
While manufacturers say the lead is found only in trace amounts and comes from naturally occurring sources, As You Sow believes the levels may be unnecessarily high.
Is Lead in Chocolate Dangerous?
Whether eating chocolate will expose your child (or you) to lead at levels high enough to cause health problems remains to be seen.
Thirty-five of the 50 chocolate brands tested were found to contain lead and/or cadmium, many at levels that exceeded California's limit. The U.S. Food and Drug Administration (FDA) states that children should not consume more than 6 micrograms of lead a day from candy. No levels are set for cadmium in food.
California's limit is stricter and limits lead exposure to 5 micrograms a day from all sources. The limit applies to everyone (not just children, as is the case with the FDA's 6-microgram limit).
For chocolate, in particular, the FDA limits lead to 0.1 parts per million (ppm), which is the level they believe causes no observable effects. California takes that limit and divides it by 1,000 to ensure no harm.1
Separate research published in the journal Talanta found that children who consume a lot of chocolate could be particularly at risk. The study concluded:2
"Children, who are big consumers of chocolates, may be at risk of exceeding the daily limit of lead; whereas one 10 g cube of dark chocolate may contain as much as 20% of the daily lead oral limit.
Moreover chocolate may not be the only source of lead in their nutrition. For adults there is almost no risk of exceeding daily limits for trace metals ingestion because their digestive absorption of metals is very poor."
Should Chocolate Sold in California Carry Warning Labels?
While As You Sow has not released exactly how much lead was detected in the chocolate they tested, they said many were contaminated above the safety threshold of California's Safe Drinking Water and Toxic Enforcement Act of 1986 (Proposition 65).
Some of the samples contained up to nine and seven times the daily amount that California considers safe for lead and cadmium, respectively. Proposition 65requires consumer products with potential reproductive toxins or cancer-causing ingredients to bear warning labels.
The labels do not apply to foods that contain low levels of naturally occurring toxins, but As You Sow believes consumers still deserve warning about lead and cadmium in chocolate. The group stated:3
"California law ensures consumers receive warnings before they are harmed. To protect consumers, companies should take immediate steps to remove these toxic heavy metals from their products or, at a minimum, to warn according to Proposition 65.
If the heavy metals are not removed, people need to be informed so they can protect themselves and their families. Consumers' input is important to food manufacturers and we, as consumers, should make companies aware that we take this issue seriously.
If your favorite manufacturer is on the warning-required list,4 call, tweet, or otherwise ask them to remove or reduce the heavy metals from their products. Investors should also consider potential risk if they own shares of these companies."
Where Does the Lead in Chocolate Come From?
The origin of the lead and cadmium in the chocolate samples is unclear. Some of the manufacturers stated the metals were the result of naturally occurring elements in the soil that were absorbed by the cocoa plants.
However, some research suggests processed chocolate products may have higher lead levels than the harvested cocoa beans, which suggests the lead contamination may be coming from another source. In 2005, researchers suggested the use of leaded gasoline could be to blame.
"Because of the high capacity of cocoa bean shells to adsorb lead, contamination from leaded gasoline emissions may occur during the fermentation and sun-drying of unshelled beans at cocoa farms," they wrote.5
Now that leaded gasoline has been phased out, this is probably less of an issue, but industrial sources of lead may still be responsible for some of the contamination.
Is Industry Responsible for Lead in Chocolate?
According to research published in Environmental Health Perspectives:6
" … industrial activities dominate the global flux of lead in the environment and have become the predominant sources of contaminant lead in many food items, including candies.
This remains true despite recent measures taken to reduce environmental lead contamination and to minimize human exposure to lead that have lowered the concentrations of this metal in foods and human populations."
It's worth noting that the Talanta study that found children may be at risk of lead poisoning from consuming a lot of chocolate also found higher concentrations of lead (and other toxins like cadmium) in cocoa butter and powder than in the cocoa bean core.
"This indicates that most of the trace metal contaminations in these products are found after the beans are harvested, dried and shipped, namely during the manufacturing of cocoa and chocolate products," the researchers wrote.7
Dark Chocolate Is a Healthy Snack
Chocolate — specifically the dark unprocessed raw kind — reduces the risk of cardiometabolic disorders, such as coronary heart disease, stroke, diabetes, and metabolic syndrome along with related problems like hypertension, elevated fasting glucose and triglycerides, high cholesterol, and abdominal obesity.8
In one study, the highest levels of chocolate consumption were associated with a 37 percent reduction in cardiovascular disease and a 29 percent reduction in stroke compared with the lowest levels!9
Other research has also shown that the antioxidant and anti-inflammatory compounds in chocolate may lower your risk of heart attack and stroke considerably.
Antioxidant polyphenols in chocolate are so valuable because they have the ability to stop free-radical-mediated oxidation, thereby directly interfering with one of the major preventable causes of chronic degenerative diseases.
Chocolate also contains other potent plant chemicals, including anandamide, named after the Sanscrit word for "bliss," which is a neurotransmitter in the brain that temporarily blocks feelings of pain and anxiety.
The caffeine and theobromine in chocolate have been shown to produce higher levels of physical energy and mental alertness, and there are likely many more healthy chocolate compounds that have yet to be discovered. The following table highlights just some of the benefits conferred by the cocoa bean.
Anti-thrombotic, including improving endothelial function
Lowers Alzheimer's risk
Anti-diabetic and anti-obesity
Reduction in C-reactive protein
Cardioprotective, including lowering blood pressure, improving lipid profile, and helping prevent atrial fibrillation
Improved liver function for those with cirrhosis
Improves gastrointestinal flora
Reduces stress hormones
Reduces symptoms of glaucoma and cataracts
Slows progression of periodontitis
Improves exercise endurance
May help extend lifespan
Protects against preeclampsia in pregnant women
What's the Healthiest Type of Chocolate?
The closer your cocoa is to its natural raw state, the higher its nutritional value. If you're after health benefits, raw cacao nibs are what you're looking for. Cacao refers to the plant, a small evergreen tree of the species Theobroma cacao, and its dried seeds, also known as cacao beans or cocoa beans, prior to processing.
Ideally, buy them whole and grind them yourself (a coffee grinder can be used for this) when using in recipes. Alternatively, you can eat them whole, just like you'd eat conventional chocolate chips. A healthy amount would probably be around one-half to 1 ounce per day. I personally grind 1 tablespoon of raw cacao nibs twice a day and put them into my smoothies.
When selecting chocolate, look for higher cacao and lower sugar content. In general, the darker the chocolate, the higher the cacao content. However, since cacao is bitter, the higher the percentage cacao, the more bitter it is (the polyphenols are what make the chocolate bitter, so manufacturers often remove them. But, it's those polyphenols that are responsible for many of chocolate's health benefits).
To counteract the bitterness, most chocolate is sweetened, so it's a matter of balancing nutritional benefit with palatability. For health benefits, choose chocolate with a cacao percentage of about 70 or higher. Milk chocolate is not a good choice as it contains both pasteurized milk and large quantities of sugar, which will significantly dampen its health benefits. White chocolate is also high in sugar and contains none of the phytonutrients, so is not a good choice either.
Due to the potential for lead and cadmium contamination, I suggest also contacting your chocolate's manufacturer to find out whether their products are regularly tested for such contaminants.
Make Your Own Healthy Chocolate Snack
In the video above, I share my recipe for a delicious yet healthy chocolate treat, courtesy of the healthy fat from coconut oil. There are no specific measurements, making it easy to tweak to your own taste. Enjoy!