Under duress, most of us can be impulsive, giving in to urges that we wouldn’t otherwise consider. I know this feeling. As I neared the end of writing my PhD thesis, I began craving dark chocolate. “But I never get cravings”, I told myself. What was up? Was I pregnant? As a man, this seemed unlikely. Eventually, I succumbed to the allure of dark chocolate, and a huge bar of the stuff later I was satisfied. I began tapping at the keypad again. Several hours later, I looked up. Only then did I realize how focused I’d been. And for once I liked what I’d written. My experience since suggests this was not a one-off, and I sincerely think that cocoa is one of the better brain boosters I’ve tried.
But is it just me?
Are there actually compounds in chocolate known to benefit brain function?
Cocoa and Chocolate
Cocoa beans come from the Theobroma cacao tree, the paste (liquor) of which can be separated into butter (fat) and solids (non-fat). Get rid of some of the butter from the paste and you get cocoa powder. Alternatively, add some cocoa butter and sugar to the paste and you get chocolate.
Cocoa Nutrient Composition
Cocoa beans (“nibs”) are more than half fat by weight, most of which is saturated or monounsaturated. The most abundant monounsaturated fat is oleic acid, the same heart health-friendly stuff that’s in olive oil. Starch and sugar make up roughly a quarter of cocoa by weight, and it’s high in fiber too. It’s also rich in many micronutrients, among which magnesium generally gets the most attention, especially since magnesium deficiency is so pervasive.
Glance at the above nutrient profile and cocoa seems quite nutritious. Yet it is the phytonutrients in the plant that have garnered the most scientific interest. And for good reason. Cocoa contains many phytonutrients, most of which are flavonoid and non-flavonoid phenols, as well as methylxanthines (1). We needn’t dwell on intricate details of phytonutrients, but I’ll glean some highlights for you.
Of the flavonoids in cocoa, flavan-3-ols such as catechin and epicatechin are highly concentrated. Catechin and epicatechin are condensed tannins, which form complexes with salivary proteins, resulting in the plant’s bitter taste. These flavonoids have many health-promoting properties that we’ll come back to.
Cocoa is also packed with the methylxanthines caffeine and its metabolite theobromine (1). Caffeine blocks the interaction of adenosine with its receptors in the brain. As adenosine disinhibits sleep-promoting neurons in the brain and reduces activity in wake-promoting ones, caffeine stimulates alertness. Theobromine is another stimulant, although it’s a weaker one than caffeine.
There is marked variation in the bioavailability of these chemicals (the methylxanthines are far more effectively taken up by your body than epicatechin, for example), but most are metabolized quite quickly, reaching peak concentrations in the blood within three hours or so. The genetics and processing of the cocoa strongly influence the concentrations of these compounds too: As you probably expect, nibs generally contain the highest concentration of phytonutrients by weight, followed by cocoa powder, then chocolate.
Cocoa and Brain Function: Mechanisms
Phytonutrients need to cross the blood-brain barrier to directly affect brain function, and it seems that catechin, epicatechin, and the methylxanthines all do so (2). This is an encouraging start. We don’t really understand how the flavonoids are then distributed within the brain, but it does seem that they accumulate in the brain with repeated ingestion (1). Because of this accrual, if researchers find that repeated cocoa consumption has cumulative effects on brain function, we can probably infer that the phytonutrients are contributing to changes in cognition.
Cocoa and Oxidative Stress
Many phytonutrients in cocoa are potent antioxidants (partly explaining why chocolate has a long shelf-life). This is one way by which cocoa seems to protect the central nervous system from noxious stimuli. As just one example of this, the vagus nerves of mice that consumed dark chocolate were less inflamed after 16 months of exposure to the polluted air of Mexico City (3).
Flavanols in cocoa protect against the death of brain cells that results from excessive inflammation. Many mechanisms contribute to this defense, a commonality of which is actions of flavonoids in lipid and protein kinase signaling pathways (4). Don’t worry, I won’t bore you with nuances of these. I’ll add that the methylxanthines also appear to be somewhat neuroprotective (5).
Cocoa, Brain Blood Flow, and Brain Communication
Adequate blood flow is critical to supplying brain cells with oxygen and nutrients while also removing neurotoxic metabolic wastes. Cocoa flavonoids increase brain blood flow in healthy young adults (6). Studies of other animals have shown that this may facilitate the formation of new blood vessels (angiogenesis) in the hippocampus (7), a seahorse-shaped structure in the medial temporal lobe of the brain that is a critical short-term memory storage depot. Cocoa flavonoids may also promote changes in communication within this brain region, which appears to be pivotal to strengthening memory traces (8).
Cocoa and Cognition
It should therefore be no surprise that consuming items rich in cocoa flavonoids has generally been shown to improve memory. Not only that, several studies have reported dose-dependent improvements in measures of brain function in humans, including attention, mental and visual processing speed, and the ability to plan, initiate, and monitor behaviors directed at achieving goals (9). Not all studies have reported improvements, but most have. Recent work has also shown that cocoa-rich chocolate helps maintain short-term memory after sleep deprivation, an effect that may be related to enhanced blood flow (10).
Why People Crave Chocolate
The foods we eat are inextricably intertwined with how we feel. Chocolate lovers tend to gravitate more to their beloved confectionary when they are down or strung out. An amusing example of this is the finding that people eat more chocolate when listening to sad music than when tuning in to uplifting songs (11). I apologize for my schadenfreude.
But why do many people find chocolate irresistible? Cocoa powder doesn’t have the same hold on them as chocolate, so they aren’t “self-medicating” a magnesium deficiency or simply seeking stimulation from methylxanthines. At the same time, white chocolate is less popular than the darker stuff, so Calories and sweetness aren’t the only variables that shape people’s preferences. Instead, the appeal of chocolate emerges from the delectable combination of great mouth feel, energy density, just the right sweetness, and the presence of phytonutrients that make us feel better.
Chocolate Affects Mood
In turn, the palatability of chocolate influences mood, for delicious chocolate improves mood more than less palatable chocolate (12). But even cocoa flavonoids alone may affect mood, for they have been shown to have antidepressant and anxiety-reducing effects in rats (13, 14).
Exactly how chocolate affects mood isn’t clear though. Some people have speculated that chocolate enhances mood because it contains two analogues of a chemical named anandamide (from the Sanskrit word ananda, meaning “joy”). Our bodies synthesize anandamide, which functions in part as a mood-lifting neuromodulator by acting on the same endocannabinoid receptors that cannabis targets. But there’s no evidence (to my knowledge) that cocoa consumption raises blood levels of anandamide.
Instead, other effects on neuromodulation may be at play (1). First, cocoa contains small quantities of endorphins and serotonin, neuromodulators that mostly improve mood. Cocoa contains other biogenic amines too such as tyrosine, an amino acid precursor to dopamine. Dopamine is a key neuromodulator in driving motivated wakefulness directed at goal achievement. The quantities of these compounds in chocolate are quite small though. And then there’s the fact that chocolate has other things in it beside cocoa that make it really tasty, and sweet, delicious foods tend to raise opioid levels (15).
Needless to say, some people indulge in too much of a good thing, and this may be a real risk with chocolate – I for one recall finding milk chocolate almost irresistible up to about the age of 15. However, the studies we’ve touched on here mostly looked at what happens when people consume cocoa, its flavonoids, or dark chocolate – not milk chocolate or white chocolate. The dark stuff contains the good stuff.
So, I recommend you opt for cocoa nibs, powders, or dark chocolate containing at least 70% cocoa (I admit that this number is arbitrary). An advantage of these choices is that most people seem to find them less moreish than sweeter alternatives – I don’t find dark chocolate quite as appetizing as milk chocolate, probably because of its astringent taste and stimulatory effects. If you opt for dark chocolate, I suggest you go for the best quality option you can afford. My favourite brand is Green & Black’s.
How much to consume depends on things like your Calorie requirements, body mass, methylxanthine tolerance, and dietary restraint – I can’t really offer a hard and fast rule. This said, I’ll reiterate the caffeine rule I used in a previous article on how to get more sleep: consume no more than about 1 mg caffeine per pound of bodyweight (2 mg per kilogram) no later than nine hours before your regular bedtime. The caffeine content of different cocoa products is quite variable, so you might want to search for the items you select. Note too that cocoa contains other stimulants, so you’ll probably experience a bigger buzz than you’d get from the amount of caffeine alone.
One important point to remember is that many of the positive effects of cocoa intake seem to accrue with repeated ingestion. So, to fully reap its benefits, you’ll also want to consume it on a relatively regular basis. You can achieve this in many ways, and you needn’t limit yourself to a single source of the stuff. You could, for example, have dark chocolate one day, cocoa nibs as a snack on another, and cocoa in your coffee on another. As a teenager, I routinely mixed cocoa powder with oats, milk, a banana, honey, creamed coconut, cinnamon, and a dash of salt at breakfast. (Potter’s Porridge – it’s the bomb.) Cocoa powder can be a great addition to smoothies, as Pro users who have tried the humanOS smoothies will know (check out smoothie #9)! You can unlock everything that humanOS has to offer by going Pro here.
Finally, think about when the best time is to leverage how cocoa influences you. It raises brain function, cardiovascular health, and mood, so I think it’s a great choice before things like public speaking, social events, sex, and exercise.
Other Benefits of Cocoa
Cocoa is probably good for the brain, so it’s no wonder that some scientists are interested in studying cocoa polyphenols in the prevention and treatment of neurodegenerative diseases such as Alzheimer’s and Parkinson’s. But it isn’t just great for your grey matter. Ginny discussed some other benefits of cocoa in a previous blog about its effects on exercise performance, and there’s also a strong body of evidence that it’s cardioprotective.
As I now reflect on the closing stages of writing my PhD thesis, I learned an important lesson: I should consume more cocoa. I’m pleased to report that this will not be a hard habit to engrain. If this blog isn’t my best work, I attribute my failure to the fact that I didn’t type it under the influence of cocoa. The good news is I have some for this afternoon.
Many of the beneficial effects of cocoa on brain function are mediated by phytonutrients, such as flavonoid and non-flavonoid phenols, as well as methylxanthines.
Cocoa flavonoids improve brain blood flow and support the integrity of neurons in brain regions important to memory.
Cocoa and chocolate have repeatedly been shown to enhance cognitive functions.
People gravitate to chocolate when stressed. In turn, consumption of chocolate tends to improve mood.
Did You Like this Blog?
If you found this blog helpful and interesting, you can fuel Greg’s capacity to crank out blogs by funding his dark chocolate consumption. If there ever was a cause to support, this is surely it. Just so you know, his favourite stuff (Green & Black’s) sets him back about $3.
Seriously though, we hope you benefit from our work and really appreciate any support.