Just like the caffeine in coffee, the cocoa in chocolate is a chemical powerhouse, rich in active compounds that are quickly absorbed, affecting everything from our energy levels to mood. Nutritionally, cocoa in chocolate contains many biologically active substances that have positive effects on human health, including flavonoids, theobromine and magnesium.
Of course, much depends on the kind of chocolate you scoff – the healthy compounds are in the cocoa, so the darker the chocolate the better it is for you.
Dark chocolate that contains at least 70 per cent cocoa is a much cheerier option than milk chocolate. Within one to two hours, the active compounds in the cocoa are absorbed into the blood stream, and give us pleasure. Chocolate contains phenylethylamine, which has some aphrodisiac-like properties. However, the body gets rid of it very quickly, so the actual effect of this is very small and more likely to be psychosomatic. But chocolate does increase serotonin and endorphin levels in the brain to give that short post-eating high. In fact, the elation really is momentary. According to a 2007 study published in the journal Appetite – chocolate soothes a bad mood for just three minutes.
There is some evidence that chocolate has a natural calming effect one to two hours after eating it. A Swiss study in 2009 found that subjects who ate 40g of dark chocolate a day over two weeks had reduced cortisol levels, our natural stress hormone.
THE FIRST BITE
Chocolate gives us immediate sensory pleasure from the taste on our tongues, and within 15 minutes sugar is converted to blood glucose that gives us an energy burst. But after an hour or so our blood glucose levels fall and “crash” – this is most severe with milk chocolate, the most sugary kind. A spike in insulin causes a lower blood sugar level than you started with, causing headaches, fatigue and lethargy.
Chocolate has appetite-suppressing properties that can help you lose weight. Not only is it high in fat, which makes you feel full for longer, researchers in Italy have found the flavonol in dark chocolate improves insulin sensitivity, which improves our ability to absorb sugars rather than store them as fat. Another study in the Netherlands showed that even smelling dark chocolate resulted in a decrease in the hunger hormone, ghrelin. This only applies to dark chocolate, as milk chocolate can often have the opposite effect. Tests in animals suggest that the flavonols in chocolate could potentially play a part in preventing obesity and type 2 diabetes.
Chocolate contains caffeine, a bowel stimulant that can trigger symptoms of irritable bowel syndrome (IBS) as it transits through the small and large intestine 4-5 hours after eating it. Caffeine also raises acid levels in our stomach, which facilitate digestion, but can also result in heartburn, acid reflux or inflammation of an existing stomach ulcer. If you struggle with acid reflux or other gut problems, you might find that chocolate tastes great going down but not so good once it hits the stomach.
An Easter egg won’t make you an immediate genius, but regular doses of dark chocolate can improve our brainpower and memory, according to a number of studies. Moreover, a report published in the New England Journal of Medicine in 2012 found a “surprisingly powerful” correlation between chocolate intake per capita and the number of Nobel laureates in various countries.
A 2012 Cochrane Group report into dark chocolate found that a couple of squares each day – about 100g – can lead to a small reduction in blood pressure. The report said flavonols in cocoa produce nitric oxide, which 'relaxes' blood vessels and makes it easier for blood to pass through them, lowering blood pressure.
Heart health and cholesterol
Several long-term studies have linked eating dark chocolate to a small decrease in “bad” LDL cholesterol, which can occur as little as two hours after eating chocolate. One study also suggests that bacteria in the stomach ferment chocolate into useful anti-inflammatory compounds that are also good for the heart health and reduce the death rate in heart attack survivors.
But any health benefits from chocolate are based on moderation and cocoa content. Most of the studies say the beneficial effects of chocolate are in the range of 80g a week. And although both milk and dark chocolate both contain cocoa, milk chocolate contains a much higher amount of dairy product and sugars. Go for dark.