Dark chocolate comes from the seed of the cocoa tree; it is known to be one of the best sources of antioxidants on the planet.
1. Dark Chocolate contains many essential nutrients
It contains a decent amount of soluble fiber and is loaded with minerals.
A 100 gram bar of dark chocolate with 70-85% cocoa contains (1):
- 11 grams of fiber.
- 67% of the RDA for Iron.
- 58% of the RDA for Magnesium.
- 89% of the RDA for Copper.
- 98% of the RDA for Manganese.
It also has plenty of potassium, phosphorus, zinc and selenium.
Of course, 100 grams (3.5 ounces) is a fairly large amount and not something you should be consuming daily. All these nutrients also come with 600 calories and moderate amounts of sugar.
For this reason, dark chocolate is best consumed in moderation.
2. Dark Chocolate is source of Powerful Antioxidants
Dark chocolate is loaded with organic compounds that are biologically active and function as antioxidants. These include polyphenols, flavanols, catechins, among others.
One study showed that cocoa and dark chocolate contained more antioxidant activity, polyphenols and flavanols than other fruits they tested, which included blueberries and Acai berries (2).
3. Studies have shown Dark Chocolate can Improve Blood Flow and Lower Blood Pressure
The flavanols in dark chocolate can stimulate the endothelium, the lining of arteries, to produce Nitric Oxide (NO), which is a gas (3).
One of the functions of NO is to send signals to the arteries to relax, which lowers resistance to blood flow and therefore reduces blood pressure.
There are many controlled trials showing that cocoa and dark chocolate can improve blood flow and lower blood pressure, but the effects are usually mild (4, 5, 6, 7).
The bioactive compounds in cocoa can improve blood flow in the arteries and cause a small but statistically significant decrease in blood pressure.
4. Dark Chocolate Raises HDL and Protects LDL Against Oxidation
Consuming dark chocolate can improve several important risk factors for heart disease.
In a controlled trial, cocoa powder was found to significantly decrease oxidized LDL cholesterol in men.
It also increased HDL and lowered total LDL in men with elevated cholesterol (8).
Oxidized LDL means that the LDL (“bad” cholesterol) has reacted with free radicals.
This makes the LDL particle itself reactive and capable of damaging other tissues… such as the lining of the arteries in your heart.
It makes perfect sense that cocoa lowers oxidized LDL. It contains an abundance of powerful antioxidants that do make it into the bloodstream and protect lipoproteins against oxidative damage (9, 10, 11, 13).
Dark chocolate can also reduce insulin resistance, which is another common risk factor for many diseases like heart disease and diabetes (13, 14).
5. Dark Chocolate May Lower The Risk of Cardiovascular Disease
The compounds in dark chocolate appear to be highly protective against the oxidation of LDL.
In the long term, this should cause much less cholesterol to lodge in the arteries and we should see a lower risk of heart disease over the long term.
It turns out that we have several long-term observational studies that show a fairly drastic improvement.
In a study of 470 elderly men, cocoa was found to reduce the risk of cardiovascular death by a whopping 50% over a 15 year period (15).
Another study revealed that eating chocolate 2 or more times per week lowered the risk of having calcified plaque in the arteries by 32%. Eating chocolate less frequently had no effect (16).
Yet another study showed that chocolate 5+ times per week lowered the risk of cardiovascular disease by 57% (17).
Of course, these 3 studies are so-called observational studies that can not prove that it was the chocolate that caused the reduction in risk.
However, given that we have a biological mechanism (lower blood pressure and oxidized LDL) then I find it plausible that regular consumption of dark chocolate can in fact reduce the risk of heart disease.
Bottom Line: Observational studies show a drastic reduction in heart disease risk for the people who consume the most chocolate.
6. Dark Chocolate May Protect Your Skin Against The Sun
The flavonols can protect against sun-induced damage, improve blood flow to the skin and increase skin density and hydration (18).
The minimal erythemal dose (MED) is the minimum amount of UVB rays required to cause redness in the skin, 24 hours after exposure.
In one study of 30 people, the MED more than doubled after consuming dark chocolate high in flavanols for 12 weeks (19).
Studies show that the flavanols from cocoa can improve blood flow to the skin and protect it against sun-induced damage.
7. Dark Chocolate May Improve Brain Function
One study of healthy volunteers showed that 5 days of consuming high-flavanol cocoa improved blood flow to the brain (20).
Cocoa may also significantly improve cognitive function in elderly people with mental impairment. It also improves verbal fluency and several risk factors for disease (21).
Cocoa also contains stimulant substances like caffeine and theobromine, which may be a key reason cocoa can improve brain function in the short term (22).
To obtain these benefits be sure to eat organic, dark chocolate with 70% or higher cocoa content.
Dark chocolates often contain some sugar, but the amounts are usually small and the darker the chocolate, the less sugar it will contain.
References:
1. http://nutritiondata.self.com/facts/sweets/10638/2
2. http://journal.chemistrycentral.com/content/5/1/5
3. http://www.ncbi.nlm.nih.gov/pubmed/18358827
4. http://jama.jamanetwork.com/article.aspx?articleid=207783
5. http://ajcn.nutrition.org/content/95/3/740.long
6. http://archinte.jamanetwork.com/article.aspx?articleid=412211
7. http://journals.lww.com/jhypertension/Abstract/2003/12000/Flavanol_rich_cocoa_induces_nitric_oxide_dependent.16.aspx
8. http://www.ncbi.nlm.nih.gov/pubmed/17513403
9. http://www.ncbi.nlm.nih.gov/pubmed/11684527
11. http://jn.nutrition.org/content/130/8/2109S.short
12. http://informahealthcare.com/doi/abs/10.1080/10715760100300091?journalCode=fra&
13. http://jn.nutrition.org/content/138/9/1671.long
14. http://hyper.ahajournals.org/content/46/2/398.long
15. http://www.ncbi.nlm.nih.gov/pubmed/16505260/
16. http://www.sacredchocolate.com/docs/sacredpdf/chocolate-consumption-reverse-atherosclerotic-plaque.pdf
17. http://www.ncbi.nlm.nih.gov/pubmed/20858571
18. http://www.ncbi.nlm.nih.gov/pubmed/16702322
19. http://www.ncbi.nlm.nih.gov/pubmed/19735513
20. http://www.ncbi.nlm.nih.gov/pubmed/16794461
21. http://hyper.ahajournals.org/content/60/3/794.short
22. http://link.springer.com/article/10.1007/s00213-004-1898-3