Examining the evidence behind chocolate's healthy reputation
Valentine’s Day conjures images of boxes filled with chocolates.
And those boxes usually contain candies that consist of a thin chocolate shell packed with stuff that's practically pure sugar.
Of course, not everything we eat needs to be highly healthful — but it’s important to distinguish chocolate that’s actually good for you from the kind that’s not.
Advertising images typically position chocolate as a devilish indulgence — but the real, dark stuff is powerfully healthful for your heart and brain.
Let’s take a closer look at the benefits of “good” cocoa and chocolate, and the nutritional distinctions between different kinds of each.
Antioxidant power: Natural cocoa and dark chocolate rule the roost
The antioxidant power of natural cocoa and dark chocolate beats that of blueberries, red wine, green tea, or black tea.
We know this because natural cocoa and dark chocolate score higher than those foods on the ORAC (oxygen radical absorbance capacity) scale and on the more reliable cellular antioxidant activity (CAA) test.
As we’ve noted many times before, foodborne antioxidants typically work indirectly, by influencing our “working” genes: see Aging Theory Gets a Radical Makeover.
Nonetheless, foods or nutrients that rank high on the ORAC and CAA scales typically deliver clinically verified health benefits.
The cocoa in chocolate is chockfull of diverse antioxidants called flavonoids (such as quercetin), most of which are found in many other plant foods.
But cocoa and dark chocolate boast extraordinarily high levels of epicatechin and proanthocyanidins, which deliver uniquely powerful health benefits.
Their unusual mix and high levels of antioxidants give cocoa and dark chocolate exceptional power to fight free radicals and inflammation and explain many (though not all) of their health benefits.
Natural cocoa and dark chocolate are also significant sources of magnesium, with 65mg per ounce of dark chocolate, or about 20% of the average adult daily requirement (see Mighty Magnesium for Bones, Hearts, Mood, & More and its links to related reports).
Just be sure to choose your cocoa and chocolate wisely — as we'll explain before we delve more deeply into their health benefits.
Choosing chocolate or cocoa: Darkness and “Dutching” matter a lot
The proven health benefits of cocoa and dark chocolate depend heavily on how they’re made and processed.
Cocoa — which typically accounts for 30% (milk chocolate) to 99% (baker’s chocolate) of a chocolate bar — is responsible for virtually all of chocolate's heart and brain benefits.
So, it’s much healthier to choose a chocolate that contains at least 65% cocoa, and best to choose an extra-dark chocolate, with 80% or more cocoa.
You can only expect health benefits from raw, unsweetened cocoa that has not been subjected to treatment with alkali — a process also called “Dutching”, which destroys about 90% of its antioxidants.
Dark chocolate is usually made with non-alkalized cocoa, but very few brands disclose whether or not that’s the case. (Vital Choice Organic Extra-Dark Fair-Trade Chocolate is made with natural, non-alkalized cocoa, and our antioxidant-content tests verify that.)
You can tell whether a cocoa has been alkalized by looking either at the front label — avoid brands labeled “Dutch Cocoa”. Likewise, avoid brands that include “alkali” in the ingredient list, because they contain only about 10% of the antioxidants found in non-alkalized cocoa.
Extra-dark chocolate contains relatively small proportions of sugar, and its dominant fat (stearic acid) is generally harmless.
But unsweetened cocoa powder is an even better source of antioxidants, because it has no sugar, and many fewer calories per gram of antioxidants.
If you prefer a bit of sweetness with your hot cocoa, try adding a little stevia or xylitol to cocoa made with unsweetened, non-alkalized cocoa powder, for a sweet, highly healthful but sugar-free treat.
When it comes to chocolate bars, choose one that consists of 80 percent or more cocoa solids, and less than 7 grams of sugar per ounce (the official FDA serving size for chocolate). And limit yourself to 1-1.5 ounces a day.
Chocolate and cardiovascular health
Lab and clinical evidence that cocoa benefits cardiovascular health has been accumulating for more than 30 years.
Specifically, chocolate can reduce oxidation of LDL cholesterol — a key promoter of dangerous arterial plaque — lower blood pressure, reduce blood “stickiness”, enhance artery performance, and help prevent harmful blood clotting.
Some of these benefits may flow from the fact that cocoa in dark chocolate inhibits angiotensin-converting enzyme (ACE) activity both in human epithelial cells and in human volunteers. (ACE inhibitors are some of the most widely used pharmaceutical drugs for treatment of cardiovascular diseases.)
Chocolate as mood-booster
In addition to antioxidants, chocolate also features mood elevators.
These include serotonin — a neurotransmitter associated with mood elevation — and amino acids called phenylethylamine and tryptophan, which is a precursor to serotonin.
Phenylethylamine prompts your brain cells to release another, more powerful mood-elevating neurotransmitter called dopamine. Chocolate also contains tyramine, which serves as a minor precursor to dopamine (tyrosine is its major precursor).
Surprisingly, white chocolate has higher levels of these neurotransmitter-boosting compounds, and appears to raise dopamine levels significantly more than dark chocolate.
That’s probably because manufacturers use the fatty, white-hued portion of cocoa to make white chocolate — leaving out the brown, antoxidant-rich carbohydrate fraction — this raises the per-ounce proportions of mood elevators.
Interestingly, people’s brains tend to produce dopamine when they eat chocolate — and even when they just think about eating chocolate.
Finally, cocoa contains a caffeine-like compund called theobromine, which exerts stimulating effects much milder than those of caffeine, and lowers blood pressure slightly by dilating blood vessels.
Its unusual content and confluence of compounds that directly or indirectly boost mood explain chocolate's reputation as a food that can make some people feel happier — even a little giddy.
Chocolate as brain-performance booster
Some of most exciting research into chocolate involves its effects on brain performance.
Natural, non-alkalized cocoa and dark chocolate are both clinically proven to enhance various aspects of brain performance.
That’s probably due to their high antioxidant content, and — less likely — because of the ability of chocolate to boost levels of key neurotransmitters.
For more on this topic, see Cocoa's Brain Anti-Aging Benefits Affirmed, Chocolate Sparks a Key Brain Protector, Extra-Dark Chocolate Eased Memory Tasks, Dark Chocolate Affirmed as Brain-Booster, Cocoa Bolstered Seniors' Brains, and Cocoa Boosted Fuzzy Brains.
Chocolate as an energy-supporting “tonic”
Scientists refer to herbs that support energy and fight fatigue as adaptogens.
And for centuries before clinical research began to affirm their effects, ancient herbalists referred to such substances as “tonics”.
Tonics and adaptogens include herbs like ginseng, rhodiola, schisandra, and ashwagandha — but it seems that dark chocolate should be added to the list.
For example, see Extra-Dark Chocolate Seen to Fight Chronic Fatigue and Can Dark Chocolate Boost Workouts?.
Chocolate for weight control?
The cocoa in chocolate may even support healthy weight loss — as long as you choose a truly dark chocolate and don’t overdo the amount.
In addition to the links above, you’ll find more in the Cocoa, Tea & Coffee section of our news archive.
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