Cocoa has enjoyed a long history of human appreciation. Did you know that cacao beans were honored as valid currency in the Mexico City region until as recently as 1887? Perhaps its because of the amazing potential health benefits of this tasty bean.

In a previous post, I've outlined what to look for when purchasing chocolate for maximum health impact. (If you haven't already read that, click here.)

Now that you've got your chocolate bar in hand, these are the top 8 benefits you might expect.

1. Powerful antioxidant protection

Oxidation is a form of chemical damage against which which we have natural defenses. However, when the rate of damage surpasses our ability to repair, accelerated aging and increased disease risk can occur. This is where polyphenols come in.

Polyphenols are plant compounds known to have a positive effect on our health via a broad range of mechanisms. One is by stoking our own internal antioxidant systems. (R) Cocoa is one of the richest sources of polyphenols in the world. (R)

Among this class of plant compounds are flavanols (a subcategory of polyphenols) which are believed to be responsible for many of cocoa's observed health benefits. Other sources of flavanols include tea and grape skins.

2. Improved athletic performance

Dark chocolate increases nitric oxide in the body, which dilates blood vessels and reduces oxygen consumption. This may allow athletes to go further for longer. (R) It also may improve sexual performance through this "lever," but that's for another post.

In one small study, flavanol-rich dark chocolate consumption (40 grams—roughly half a bar—per day for 14 days) increased cycling endurance by 17% compared to eating flavanol-poor white chocolate. The dark chocolate also reduced the amount of oxygen used when cycling during a 2 minute sprint. (R)

3. Reduced cognitive aging

The hippocampus is the brain's memory center, and is among the most vulnerable structures in the brain. It is damaged by chronic stress and Alzheimer's disease.

One of the most important parts of the hippocampus is the dentate gyrus. It's this small region where adult neurogenesis—the creation of new neurons throughout life—is known to occur.

Dysfunction of the dentate gyrus typically accompanies "normal" aging, but dark chocolate seems to offer protection to this vulnerable structure. In a randomized control trial involving healthy, middle-aged adults, cocoa flavanols reversed age-related memory decline in healthy older adults by improving function of the dentate gyrus. (R)

4. Greater mental acuity

In the aforementioned study where cocoa flavanols improved functioning of the dentate gyrus, the human volunteers also showed significant improvement in tests of memory. (R) This has been borne out in long-term observational research where cognitively healthy people who ate chocolate at least once a week had stronger cognitive performance on visual-spatial memory, working memory, and abstract reasoning tests than those who consumed little to no chocolate. (R)

5. Better vascular function

Partly because of chocolate's ability to boost nitric oxide, consuming dark chocolate acutely improves endothelial function and can reduce blood pressure. (R, R) The endothelium is the dynamic, one-cell-thick lining of your blood vessels that constrict and expand according to metabolic needs, and dysfunction is thought to be a predictor of cardiovascular risk—and likely of dementia as well. (R, R)

The beneficial effects of chocolate on vascular function are blunted when the chocolate bar contains a lot of sugar, however. (R) (See my guide on how to buy the best chocolate, here.)

6. Healthier, better looking skin

The flavonols in cocoa might protect against sun damage. In one study, participants were instructed to eat 20 grams of flavanol-rich dark chocolate daily for 3 months. When subjected to UV light, the favanol-rich chocolate group (but not the control group) showed greater resilience to sunburn. (R)

Chocolate also helps increase blood flow to the skin, probably due to its positive effect on vasculature. (R) It seems to enhance hydration, skin texture, as well as subjective appearance of skin. One study even found that 6 weeks of flavanol-rich chocolate consumption was able to reduce wrinkles and the visible effects of sun damage on skin. (R

7. Improved blood lipids

Dark chocolate seems to be a potent HDL booster. (R) HDL is thought to be the "good" cholesterol. Though this is an oversimplification (HDL carries cholesterol), low HDL is thought to be a risk factor for cardiovascular disease (although recent research has challenged this idea (R)).

More importantly, cocoa flavanols might protect your lipoproteins (these include HDL and LDL) against oxidation. (R) Oxidized lipids are highly damaging to our blood vessels. 

8. Better metabolic health

In a placebo-controlled trail of 90 adults with mild cognitive impairment (often considered pre-dementia), those that were given moderate- to high-flavanol cocoa supplements showed an improvement of insulin sensitivity. (R) Insulin sensitivity is a marker of metabolic health (how well your body creates energy from food and oxygen) and insulin resistance is the hallmark of type 2 diabetes. Patients in this trial also showed improved cognitive function.

How often do you consume chocolate? How does it make you feel? Let me know in the comments below!