Dark chocolate, does eating it provide health benefits? Are there risks beyond the added sugar and fat to your diet?
History
Since around 1900-1500 BC, dark chocolate has been cultivated in Mexico and South America. Initially it was served as a drink for ceremonial and medicinal purposes, and also as a luxury for Mayan and Aztec elites.
In the 1600s, it was argued that “chocolate” should be considered a medicine because it changed a patient’s health. At that time, physicians also stated that all that was necessary for breakfast was chocolate, because it yielded good nourishment for the body.
In 2021, the global premium chocolate market size was valued at USD 75.32 billion in 2021. It is estimated to grow about 10% each year.
Dark Chocolate Health Benefits
In clinical studies, daily consumption of high flavanol dark chocolate (~200-1000 mg flavanols/day) provided:
- modest improvements in blood vessel function, lower blood pressure, and a lower risk of heart disease.
- a significant 27% reduction in cardiovascular death and greater cardiovascular benefits among those taking it regularly.
- “good” cholesterol increases and “bad” cholesterol reductions, each by over 10%.
- moderate to large memory and executive function improvements.
- production of serotonin and endorphins, helping you feel good in part because of how it lubricates your mouth.
- endogenous photoprotection for the maintenance of skin health, reducing UV light damage and wrinkles while maintaining skin elasticity.
Which Dark Chocolate Brand for Health Benefits?
Consumer Lab and Consumer Reports discovered that some brands of dark chocolate contain levels of cadmium and lead. The lead levels found range from 1 to 1.9 mcg per serving, well below the FDA guidelines of under 12.5 mcg per day. Cadmium is a kidney toxin with a safe daily limit of 4.1 mcg for adults and 3 mcg for children. It has a half-life in the body of 10-35 years, so it accumulates over time. Many brands exceed this limit per serving size. See the Consumer Reports article so you can avoid them.
Consumer Lab has run tests to identify dark chocolate brands with the highest levels of flavonoids and lowest levels of cadmium. They recommend CocoaVia’s Cardio Health or Brain Health Memory+, each with over 500 mg per gram of flavanols.
Consumer Reports recommends Mast, Taza, Ghirardelli and Valrhona as safe for those who prefer chocolate bars, albeit with significantly lower levels of flavanols. Ghirardelli 72% Intense Dark has 12.7mg/g of flavanols or 318 mg per two piece serving, the second highest concentration of flavanols among chocolate bars tested by Consumer Labs. Ghirardelli 86% contains one of the lowest levels of cadmium reported.
Dark Chocolate Health Benefits Dosage
Either consume two tablets of CocoaVia or enjoy a couple ounces of 70%+ high flavonoid dark chocolate after breakfast. Why after breakfast? Caffeine ingestion later in the day can impact high quality sleep as it takes 11 hours to leave your system.
Dark Chocolate Clinical Trials
There are 78 clinical trials testing dark chocolate on a variety of health indications. Dosages range from 200 mg to 1064 mg of flavonoids. Although funded by a chocolate manufacturer, the most comprehensive recent result is the following:
The Cocoa Supplement and Multivitamin Outcomes Study (COSMOS), funded by Mars Edge, was a randomized, double-blind, placebo-controlled trial testing a cocoa extract supplement (containing 500 mg/d flavanols), and a multivitamin supplement in the maintenance of cardiovascular health and cancer risk in a total of 21,442 participants, including 12,666 women aged ≥65 years and 8,776 men aged ≥60 years with an average of 3.6 years of treatment and follow-up.
COSMOS provides suggestive evidence that long-term cocoa extract supplementation may impact clinical cardiovascular outcomes, including a significant 27% reduction in cardiovascular death and greater cardiovascular benefits among those taking the study pills regularly.
Dark Chocolate Side Effects
Most brands of dark chocolate also contain sugars and unhealthy saturated fat. Eating large amounts can cause caffeine-related side effects such as nervousness, increased urination, sleeplessness, and a fast heartbeat. Additionally, from RXList:
- Anxiety: There is a concern that the caffeine in large amounts of cocoa might make anxiety disorders worse.
- Bleeding disorders: Cocoa can slow blood clotting. Consuming a lot of cocoa might increase the risk of bleeding and bruising in people with bleeding disorders.
- Heart conditions: Cocoa contains caffeine. The caffeine in cocoa might cause irregular heartbeat in some people and should be used cautiously in people with heart conditions.
- Diabetes: Cocoa seems to be able to raise blood sugar levels and might interfere with blood sugar control in people with diabetes.
- Diarrhea. Cocoa contains caffeine. The caffeine in cocoa, especially when taken in large amounts, can worsen diarrhea.
- Gastroesophageal Reflux Disease (GERD): Cocoa seems to hinder the effectiveness of the valve in the food tube (esophagus) that keeps the contents of the stomach from coming back into the food tube or the airway. This could make the symptoms of GERD worse.
- Glaucoma: Cocoa contains caffeine. The caffeine in cocoa increases pressure in the eye and should be used cautiously in people with glaucoma.
- High blood pressure: Cocoa contains caffeine. The caffeine in cocoa might increase blood pressure in people with high blood pressure. However, for people who already consume a lot of caffeine, it might not cause a big increase.
- Irritable bowel syndrome (IBS): Cocoa contains caffeine. The caffeine in cocoa, especially when taken in large amounts, can worsen diarrhea and might worsen symptoms of IBS.
- Migraine headaches: Cocoa might trigger migraines in sensitive people.
- Osteoporosis: Cocoa contains caffeine. The caffeine in cocoa might increase how much calcium is released in the urine. Cocoa should be used cautiously in people with osteoporosis.
- Surgery: Cocoa might interfere with blood sugar control during and after surgical procedures. Stop eating cocoa at least 2 weeks before a scheduled surgery.
- Rapid, irregular heartbeat (tachyarrhythmia): Cocoa from dark chocolate can increase heart rate. Cocoa products might also make irregular heartbeat worse.
Dark Chocolate Drug Interactions
Because dark chocolate lowers blood pressure and is a stimulant, there are many medications which can have adverse interactions. Please see the full list. Here are a few.
Dark chocolate consumption should not be mixed with medications that:
- slow blood clotting such as anticoagulant or antiplatelet drugs.
- provide treatment for diabetes or depression.
- impact blood pressure or are stimulants
- interact with caffeine (there are many. See list…)
Conclusion
We hope you found this article on dark chocolate helpful. Your reward for reading this article and focusing on your health is to enjoy a daily dosage of dark chocolate with your next breakfast, but only if it is safe for you. If not, then perhaps another option from the list of tasty and healthy foods such as cherries, blueberries, strawberries, peaches, nectarines or almonds.
Data Sources
Dall-E (digital art)
