Easter is traditionally the time of the year when most chocolate is consumed – usually guiltily because we think of chocolate as an unhealthy food and something your doctor certainly wouldn’t approve of.
But now new research from the University of Helsinki in Finland has found that mothers who consumed more chocolate during pregnancy (i.e. they ate chocolate every day as opposed to those mothers who just had some weekly or hardly ever) produced babies who at their six month follow-up were rated by the mothers themselves as having considerably more pleasant temperaments.

Dr Katri Raiddonen and colleagues, who published the study in the journal Early Human Development, suggest one explanation for the intriguing finding is that the chocolate mothers consume during their pregnancy is having a profound effect on the brain development of their babies while in the womb.
It was notable that the mothers in their study who were most stressed during their pregnancy tended to produce babies who at six months were also more stressed and fearful. However, those mothers who were stressed during pregnancy, but ate a lot of chocolate, seemed to produce babies who had significantly less negative temperaments at six month follow up. It was almost as if the chocolate was acting as some kind of “treatment” for the future stress of the babies, or a stress buffer between mother and child.

That a mother’s eating habits and her biology during pregnancy could have profound future effects on her child is an idea gathering pace in medicine. So the notion that maternal chocolate consumption could influence the biological future of children is not as far-fetched as it sounds.

For example, we now know that babies born with lower birth weights – but not abnormally low weights – are more prone to higher blood pressure as adults and even to higher death rates from coronary heart disease. This is known as the foetal origins hypothesis in medicine: the idea that what happens to us as adults in terms of our health was actually pre-programmed astonishingly long ago by our experiences in the womb.

Women who are very thin during pregnancy are known to produce babies who are more prone to raised blood pressure later in life. Taller women produce babies who, when measures 70 years later, tend to have lower bone mass, even after adjustment for adult height.

We don’t know why what happens to you in the womb should have such profound effects many decades later. But one theory comes from the observation that in nature generally there appears to be biological mechanisms at work whereby embryos are sent information via the womb as to conditions in the outside world, in order to prepare them for the environment outside. If the foetal origins hypothesis is correct, then women should look after themselves particularly carefully during pregnancy.

The African armyworm moth (Spodoptera exempta) is a good example. If the caterpillars are undernourished as a result of overcrowding, they develop into moths with a metabolism that is primarily dependent upon fatty acids. Fatty acids are the fuel required for long-distance flights and in this way the adults are better adapted to migrate to other, less-crowded, places.

Chocolate has several pharmacologically active ingredients which are believed to alter mood and behaviour. These include cannabis-like substances and phenylethylamine (PEA), a chemical structurally and pharmacologically similar to amphetamine. Both of these substances profoundly affects the brain’s mood centres.
PEA is produced naturally by the brain, stimulating and elevating mood. It has also been found to be reduced in the tissues and fluids of the depressed – while administering PEA has been found to ameliorate some types of depression.

PEA is structurally related to MDMA, otherwise known as ecstasy, an increasingly common drug of abuse in Britain today, which can produce psychotic breakdowns. A recent study found that seven regular abusers of ecstasy also suffered intense cravings for and had episodic binges on chocolate. The authors of that study concluded that the link with drug-induced psychosis suggests chocolate’s pharmacology deserved more attention than it currently receives from doctors.

Indeed, chocolate has such profound effects on the brain (look around you during Easter) that some doctors have begun to question whether chocolate should not be reclassified as a drug. The case for this was argued in a recent paper in the journal of the American Dietetic Association, Chocolate: Food or Drug?, by Kristen Bruinsma and Douglas Taren of the University of Arizona College of Medicine.
Chocolate is by far the food item that is most commonly the subject of severe cravings – terms like chocoholic and chocoholism reflect this.

Chocolate cravings appear to exist in 40 per cent of women, but only 15 per cent of men. Three quarters of both sexes claim that no other substance will appease their desire.
The strong attraction of the female brain to chocolate has been exploited by advertisers – the mysterious man in black delivers chocolate because the lady loves…. This actually appears to have a real neuroscientific basis which could be explained by another recent finding: that women tend to crave chocolate at certain specific points in the menstrual cycle, usually around the time of or just before a period starts. Research has established that chocolate is the only high carbohydrate food that is craved more at menstruation than at other times during the menstrual cycle.

Premenstrual syndrome is strongly linked with magnesium deficiency in some women. Chocolate and cocoa powder contain exceptionally high concentrations of magnesium. Indeed, in some studies, taking magnesium supplements has subdued chocolate cravings, suggesting that some chocolate consumption may be the body’s attempt to top up its magnesium.

But before you all rush out and stock up on chocolate, it’s important to add the caveat that we still understand very little about the complex pharmacology of chocolate. We know that chocolate contains many other chemicals yet to be properly analysed and understood, for example stimulants like caffeine and related substances, as well as other constituents known to increase serotonin release in the brain. Serotonin is one of the chemicals anti-depressants act on. It also appears to increase when chocolate is consumed.
So the true story of chocolate and its complex effects on our brain is far from being finally elucidated. There are several problems with current theories, for example sausages also contain a lot of PEA, but are not normally associated with the same kinds of cravings as chocolate. Similarly, nuts contain high concentrations of magnesium and are not as sought after as chocolate.

Also, if you give chocoholics chocolate in the form of capsules to swallow, rather than as a nice tasting bar, they are still theoretically getting the same levels of PEA and magnesium, but the capsules don’t seem to ameliorate their cravings as much as they should do if mere biochemistry were the key.
Perhaps the key factor is what food experts refer to as the “mouth-feel” of chocolate – the sensation of the substance in your mouth that is strongly linked to its pleasure. We know that intense pleasures like this are linked to the release of the brain’s own endogenous heroin-like substances, so perhaps it’s the combination of taste plus complex biochemistry which underlies the enigma of chocolate.

Indeed, the pleasure associated with chocolate consumption is so intense, that it is also linked to strong feelings of guilt in many studies – an emotional construct which means chocolate probably comes closest psychologically to the two most intense experiences of all: sex and drugs. Perhaps the real reason the mothers who freely indulged in chocolate from University of Helsinki study were less stressed and produced less stressed babies is actually psychological.

They simply were not the subjects of self-imposed restraint concerning chocolate and other guilty pleasures the stressed mothers were suffering from, and this in turn reduced their stress.
The mystery of chocolate is that although other foods are clearly desired and therefore expensive, such as caviar, people still don’t declare their love with a heart-shaped box of it – and no-one, but no-one, makes a 3 am run to the 24-hour supermarket for nuts.