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Why chocolate really is the secret to happiness

Money may not buy happiness or grow on trees but when it comes to chocolate, it seems you can have both. Chocolate really does grow on trees and the chemical feel-good factor comes from the world’s most…

Chocolate heaven. Charlie Dave, CC BY

Money may not buy happiness or grow on trees but when it comes to chocolate, it seems you can have both. Chocolate really does grow on trees and the chemical feel-good factor comes from the world’s most widely consumed psychoactive drug.

The Theobroma cacao is an evergreen that is native to tropical regions of the American continent and its seeds or beans are the source of the 4m metric tonnes of chocolate produced each year, and much of it from countries like the Ivory Coast and Indonesia.

Chocolate consumption goes back at least 4,000 years, to the peoples of present day Mexico: the Mayans, Aztecs and their predecessors, the Olmec. Just as today, they roasted the fermented seeds from cocoa pods, grinding the roast to a powder which they used to make a chocolate beverage, a cold, foaming drink that was very different to the substance we consume today. Sometimes they added honey to sweeten it and the Aztecs also added chili-pepper to give the phrase “hot chocolate” a whole new meaning.

Two thousand years ago the Mayan people, of what is now known as Guatemala, even came up with the original “chocolate teapot”, a ceramic vessel used to pour the foaming drink and archaeologists have found evidence that chocolate drinks were served up at the celebrations after the interment of sacrificial victims (though I’m not sure that the condemned would have been made any happier with a bar of chocolate).

Montezuma’s secret

The last Aztec emperor Montezuma II consumed a lot of this drink every day, and it was hinted that this enhanced his virility. No wonder the Spaniards were interested. Of course, it was the Spaniards who brought this wonder drink back to Europe, but adding sugar and spices like cinnamon and vanilla, another import from the Americas, transformed it into the much sweeter drink we have now. Chocolate drinking became the thing to do in fashionable society.

Less than 200 years ago, the invention of the chocolate press by Casparus van Houten senior made it possible to separate roasted cocoa beans into cocoa butter and a solid that could be made into cocoa powder. This powder could be recombined with sugar and cocoa butter to produce an eating chocolate, and in 1847 the Bristol Quaker firm of Fry’s, closely followed by Cadbury’s in Birmingham, made the first chocolate bar. The Swiss came up with milk chocolate bars in the 1870s, and to this day Switzerland and Britain are two of the top nations for chocolate consumption. Chocolate Easter Eggs were invented in the 1870s, and we haven’t looked back since.

Chemical sensations

The taste of chocolate comes from a mixture of chemicals, many resulting from the roasting process, in which sugars and amino acids combine, forming members of a family of molecules called pyrazines, which contribute the nutty, roasted and chocolately sensations.

But what about the “feel-good” side of chocolate? For a start, there is the world’s most widely consumed psychoactive drug: 1, 3, 7-trimethylxanthine by name. You may have heard of it: we call it caffeine. It works by counteracting the natural neurotransmitter adenosine, resulting in an increase in heart-rate and muscle contraction. There is also a significant presence of theobromine in chocolate, a similar stimulant which also happens to be the molecule that makes chocolate poisonous to dogs. Then there is serotonin, a natural neurotransmitter which controls many functions in the brain, including mood and behaviour. The body makes it from the natural amino acid tryptophan and chocolate contains both serotonin and tryptophan.

Another chocolate molecule believed to be important was discovered less than 20 years ago: anandamide. This binds to receptors in the brain known as cannabinoid receptors. These receptors were originally found to be sensitive to the most important psychoactive molecule in cannabis, Δ9-THC. Likewise, anandamide and similar molecules found in chocolate are also thought to affect mood.

Phenylethylamine, another family of chemicals, is found in chocolate in very small amounts. It is a naturally occurring substance with a structure that is closely related to synthetic amphetamines, which of course, are also stimulants. It is often said that our brain produces phenylethylamine when we fall in love, and it acts by producing endorphins, the brain’s natural “feel-good” molecules. The bad news, however, is that eating chocolate is probably not the best way of getting our hands on phenylethylamine as enzymes in our liver degrade it before it can reach the brain.

There are yet more other molecules in chocolate – especially in dark chocolate – like flavonoids, which some scientists think may help improve cardiovascular health (but chocolate manufacturers have been known to remove bitter flavanols from dark chocolate).

There is one feel-good factor I’ve not mentioned, which isn’t a molecule – the melt-in-your mouth sensation. The fatty triglycerides in cocoa butter can stack together in six different ways, each resulting in a different melting point. Only one of these forms has the right melting point of about 34 degrees, so that it “melts in your mouth, not in your hand”. Getting the chocolate to crystallise to give this form is a very skillful process, the product of very careful chocolate engineering.

There is still much yet to know about chocolate and some are now even sequencing the genome of cultivated cacao. But the continuing intricacies in chocolate and cacao that we are discovering through science can only add to the very simple human pleasure of breaking off a piece and popping it in our mouths.

Join the conversation

7 Comments sorted by

  1. Peter Reynolds

    logged in via Facebook

    Please clarify the statement that anandamide is a 'chocolate molecule'?

    Anandamide is an endocannanbinoid, the equivalent of the phytocannabinoid THC. Do you mean that chocolate/cocoa contains a different phytocannabinoid related to THC/AEA? How can an endogenous cannabinoid be present in chocolate?

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    1. Simon Cotton

      Senior Lecturer in Chemistry at University of Birmingham

      In reply to Peter Reynolds

      Dear Peter

      In 1992, Mechoulam and co-workers characterised anandamide, a molecule found in porcine brain in a paper "Isolation and structure of a brain constituent that binds to the cannabinoid receptor" (Science, 1992, 258,1946-1949). They suggested that "anandamide may function as a natural ligand for the cannabinoid receptor." In 1996, di Tomaso, Beltramo and Piomelli published a paper "Brain cannabinoids in chocolate" (Nature, 1992, 382, 677–678) reporting they had detected anandamide and related molecules in commercial cocoa powder.
      Best wishes
      Simon

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    2. Peter Reynolds

      logged in via Facebook

      In reply to Simon Cotton

      Thanks Simon. I'm not sure that makes me any the wiser but I'll keep eating the chocolate and smoking the weed!

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  2. Sue Ieraci

    Public hospital clinician

    Since when was this a secret?

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  3. Comment removed by moderator.

  4. Fielding Dupuy

    logged in via email @comunicandes.com

    Simon,

    I enjoyed reading the article very much.

    I'd like to draw your attention to the a competing theory about the origins of chocolate. A recent French-Equadorean archeological study found vestiges of chocolate in pottery of the Mayo-Chinchipe people in southeastern Ecuador predating the earliest finds from Mexico. With all due respect to Mesoamerica, this idea that Ecuador is the original source of chocolate is bolstered by the fact that today Ecuador contains more genetic diversity in cacao than found in any other nation and is seen by industry experts as the source of the world's finest cacao beans.

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    1. Simon Cotton

      Senior Lecturer in Chemistry at University of Birmingham

      In reply to Fielding Dupuy

      Dear Fielding,

      Thank you for your kind words. I wasn't aware of the archaeology carried out in Ecuador. If you can post details of where the work has been published, I'll be interested to read more (as will other readers of this blog)

      Regards

      Simon

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