Review Chocolate-divine food, fattening junk or nutritious supplementation?
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European Journal of Clinical Nutrition (1997) 51, 341±345
ß 1997 Stockton Press. All rights reserved 0954±3007/97 $12.00
Review
ChocolateÐdivine food, fattening junk or nutritious
supplementation?
S RoÈssner
Obesity Unit, Karolinska Hospital S-171 76 Stockholm, Sweden
Descriptors: body weight; chocolate; cocoa bean; craving; sugar
Introduction designated to plant these beans were kept away from their
women several days before the work. Their opportunity to
Chocolate is an interesting food for numerous reasons. Its
meet again with their partners immediately after the beans
historical background and mystical nimbus, its hedonic
had been planted would ensure that their sexual activity
potential and its nutritious properties have all contributed
was also transferred into the growth of the beans.
to make chocolate a fascinating and controversial food
component. This review will describe brie¯y the historical
background and the development of modern chocolate
products, the sensory and hedonic properties of chocolate, Cocoa beans to Europe
the medical risks and bene®ts associated with chocolate The beverage which Christobal Colon and later Hernando
consumption and some of the modern myths surrounding Cortez encountered in America was something quite dif-
chocolate. ferent from what we today regard as chocolate. `Xocoatl',
meaning `noisy water' (Mueller, 1957), was made of
roasted ground beans resembling cocoa mass. Spices were
Historical background (Nielsen, 1995) added which made the drink either red or black. It was said
The cocoa bean has a complex historical background. that Montezume consumed more than 50 golden cups of
Besides being an important ingredient in a drink only this drink daily. Christobal Colon returned in the beginning
available for the highest in the Aztec society, the cocoa of the 16th century with some cocoa bean samples, but in
beans were as close as one could get to a uni®ed monetary Europe nobody showed great interest at that time. Twenty
system in the middle Americas of the Aztecs and the years later the interest had grown and it became suddenly a
Mayas. Tax was paid in cocoa beans and it is possible to habit, con®ned to the Spanish nobility to consume the
reconstruct price lists from that time. A large pumpkin or a chocolate drink. The secret was kept with the help of
turkey was 4 beans, a prostitute over night 10 beans. For monks and the harvest from the colonies was strictly
100 beans a healthy slave could be bought. The role of the reserved for the high class of the Habsburg empire. As
cocoa bean as a combined nutrient and monetary system with any other food or drink which is available in restricted
was obviously unique. In a letter to the pope Clemens VII amounts, chocolate was immediately given special proper-
Peter the Martyr writes about the cocoa beans and describes ties. Both Madame DuBarry (later called Madame Pompa-
them as `blessed money which prevent the owner from dour) and the venetian Casanova argued that chocolate
greed, since they cannot be stored or hidden in the earth'. functioned as an aphrodisiac. In the middle of the 17th
The fact that the cocoa tree was the basis for a monitory century Dr Henry Stubbs wrote a thesis about chocolate,
system gave it its ®rst Latin name Amygdalae pecuniariae, called `The Indian nectar' stating that `chocolate
literally `money almond'. However, Linne later exchanged . . . provokes lust like nothing else'. Statements of this
the term and rather underscored the divine and culinaric kind could only have one effect: The interest in chocolate
aspects of the tree products, calling it Theobroma cacao. rose dramatically.
Plantation of the cocoa tree was a holy ritual and the Since chocolate had become so popular in 16th century
farm workers of the Maya people had a god of their own Spain it also came under the scrutiny of the pope. In 1569
who was worshipped to ensure a rich crop. This god Pius V was served a cup of chocolate and found it so
Ekchuah was thoroughly celebrated in a happy ceremony disgusting that he was convinced that nobody would make
which did not require any human sacri®ce, only the killing drinking chocolate a habit. For this reason it was not even
of a dog, provided it had a cocoa coloured patch in its skin. considered necessary to ban the decoction. However, other
When the beans were planted this had to take place during pure catholics were unhappy with this decision and numer-
optimised circumstances. The beans were exposed for ous dissertations were written to establish whether choco-
moonlight for four nights and the farm workers who were late was a food or a drink and whether it would be allowed
to consume it on holidays and during fast. In 1662 the
Received 10 November 1996; accepted 30 January 1997 cardinal Brancaccio declared that `liquidum non frangitChocolateÐdivine food
S RoÈssner
342
jejunum', that is drink does not break the fast, but the which results in temperatures above 50 C, the beans lose
controversy lasted into the next century. Drinking chocolate their adhering pulp and after 4±6 d are ready to be dried.
became so popular that high society ladies even had cups of After one week of drying in good sunshine a stable product
the drink brought into church during mass. When Anne of is obtained which can be stored and transported. However,
Austria, daughter of the king of Spain, married Louis XIII not even at this point has the distinctive chocolate ¯avour
of France in the year of 1615 she brought with her not only yet been developed. In spite of considerable work it has not
her own chocolate but also a servant named LaMolina been possible to identify the characteristic chemical com-
whose main chore it was to prepare the chocolate. Choco- pounds which constitute the chocolate ¯avour. More than
late became immediately very fancy and in several Eur- 400 identi®ed compounds in the end product seem to be
opean countries the sovereigns in vain tried to prevent the responsible for the ¯avour and aroma we refer to as
consumption. After some years it was realised however that chocolate.
chocolate houses might be a better alternative to the coffee During roasting the moisture of the bean is further
shops, which in turn had developed as alternatives to the reduced to below 2% which also makes it easier to
pubs. The hope of the authorities was that there would be remove the adhering shell. After milling to a particle size
less gambling, intrigue making and conspirations in the < 100 m a suspension of solid cocoa particles within a
chocolate houses than in the preceeding coffee houses, a matrix of liquid cocoa butter is obtained. This material
hope that certainly was not ful®lled. Chocolate spread all named `cocoa mass' or `cocoa liquor' is the starting
over Europe and when it could not be prohibited, the material for the further manufacture of chocolate. The
governments at least tried to tax the produce exactly as cocoa press invented by van Houten made it possible to
had been done with liquor, coffee and tobacco. separate the cocoa butter from the fat free cocoa solids,
During these years the product had developed and was which contains far the main part of the characteristic cocoa
now served as a sweet drink containing the entire compo- ¯avour. The cocoa butter is unique due to its composition
nents from the dried and roasted cocoa bean but with sugar of 35% stearic acid, 35% oleic acid and 25%
and vanilla added. Sometimes starch was added as initially palmitic acid, which, along with a considerable amount
in Mexico to provide a more homogenous soup. Still the of a-tocopherol, determines its natural stability against
preparation of a cup of chocolate was a tidious and hard oxidation.
work requiring 30 min of whipping of the hot mixture in a In the production of chocolate products particle size
bowl. reduction is necessary to give chocolate the creamy texture
and hedonic properties that chocolate consumers expect.
With smaller particle sizes of ingredients such as dried
Modern chocolate products milk, sugar and cocoa solids higher quality follows. An
In 1828 a technical breakthrough came. The Dutch Coen- important property of chocolate is that the melting curve
raad van Houten separated the cocoa butter and milled the for cocoa butter shows a transition from a hard material to
remains to cocoa powder. Peter Vevey in Switzerland liquid oil at mouth temperature.
added milk to the product in 1878 basically creating the Chocolate has a strong and complex ¯avour. This is one
modern chocolate of today. reason why chocolate can be used to mask undesirable
Chocolate has a ¯avour and a texture unlike any other ¯avours and thus help to convey acceptability to foods and
(Morgan, 1994). The tree and the ¯ower from which it beverages which are nutritionally superior or to drugs
grows, the pod and its seed and the treatment of the product which might be more easily consumed by children if a
are different from those of any food ingredient. Cocoa disagreeable taste is masked by the more attractive choco-
beans are a tree crop from small trees, generally planted late (Hoskin, 1994).
under larger trees providing shade and protection from the
wind. Most cocoa beans are harvested in geographical areas
Chocolate consumption patterns
close to the equator ( 10 north and south).
Cocoa beans were originally cultivated by the Aztecs The per capital chocolate candy consumption shows an
and the Mayans from Central and South America. After the interesting distribution pattern which only to a small extent
discovery of this part of the world the cocoa trees gradually agrees with data for overweight and obesity distribution
spread over other tropical parts of the world and today (Seligson et al, 1994). The highest consumption is reported
almost 50% of the entire cocoa production comes from from Switzerland (9.9 kg/y). In the United States, which
West Africa. A considerable part is also grown in South has the highest mean body mass index in the western world,
East Asia (Indonesia and Malaysia). the chocolate consumption is less than half of the Swiss
The cocoa tree is peculiar in several respects (Hoskin, ®gures (4.6 kg/y). Interestingly, Denmark, Norway and
1994). In contrast to most fruit or nut trees which have a Sweden are among the top ten states with Norway second
distinct time for pollination followed by a well-de®ned in the world (7.9 kg/y). The Finnish annual consumption is
harvest time, cocoa trees continuously produce ¯owers and only 3.5 kg/y in a country known for a high prevalence of
mature fruits at the same time. In some parts of the world obesity, coronary artery disease and premature athero-
cocoa pods can be harvested during nine months of the sclerotic complications. Of the countries in South East
year. The pods are cut from the tree by hand and the beans Asia only Japan is found with 1.7 kg/y.
are removed from the pod by a manual procedure. The American studies have described the chocolate candy
cocoa butter and the cocoa solids are isolated within the eating pattern during the day in the 1987±1988 National
cotyledons of the bean and surrounded by water which Food Consumption Survey which demonstrates that only
must be removed. The cocoa taste develops during the 34% of all chocolate is consumed at breakfast, lunch and
ensuing two processes of fermentation followed by drying. dinner (Table 1). The rest of the chocolate consumption can
During fermentation pulp sugars are converted to alcohol be observed as snack foods generally starting in the early
and from alcohol to acetic or other organic acids in addition afternoon. During the time period 20.00±24.00, 22% of all
with several other biproducts. During this active process chocolate consumption takes place. More chocolate isChocolateÐdivine food
S RoÈssner
343
Table 1 Chocolate consumption pattern over the day. Data from US
National Food Consumption 1990
their patients to avoid chocolate products and in many
cases this approach seems to be founded more on moral
Chocolate time % than on scienti®c grounds. Some recent studies have
demonstrated that chocolate in the diet may not have the
Breakfast 2
Lunch 18 adverse effects anticipated. Kris-Etherton et al (1993)
Dinner 14 studied the effects of whole food diets high in stearic
acids where one of the experiments included cocoa
34% butter. They study demonstrated that this diet elicited a
Snacks
00±04 h 2
neutral cholesterolemic response in comparison with a
04±08 h 1 corresponding diet where the fat source included dairy
08±12 h 7 butter. In a later study (Kris-Etherton et al, 1994) it was
12±16 h 21 demonstrated that when a milk chocolate bar was con-
16±20 h 13 sumed instead of a high-carbohydrate snack HDL-concen-
20±24 h 22 66%
tration increased and plasma triglycerides fell signi®cantly.
100% The authors speculate that the relative hypocholesterolemic
effect of the cocoa butter diet can be attributed to the high
proportion of stearic acid.
In treatment of diabetic teenagers the need for three
consumed in the winter than in any other seasons. Overall main meals and two snacks is generally underscored as a
chocolate candy seems to be a minor contributor (0.7± cornerstone of the dietetic treatment. For historical reasons
3.4%) to the dietary intake of total energy, fat, saturated milk chocolate bars and potato chips, which obviously are
fatty acids and stearic acids. This of course does not popular snacks among teenagers, have been considered
exclude the fact, that for individuals, chocolate might be inappropriate for these patients. Cedermark et al (1993)
even the main source of energy intake. decided to evaluate the glycemic response of these popular
snack foods compared to a more regular reference diabetes
Nutritious properties of chocolate snack (sandwich and apple). The study demonstrated that
an occasional exchange of such regular diabetes afternoon
The major component of cocoa mass (cocoa liquor) are: snack for an isocaloric amount of a milk chocolate bar or
54% cocoa butter, 11.5% protein, 9% cellulose, 6% tannic potato chips did not have any negative effect on the
acids and colour, 5% water, 2.6% mineral salts, 1.2% postprandial blood glucose curve and thus is helpful in
theobromin, 1.0% sugars, 0.2% caffeine and 9.5% organic providing these children with a wider and more acceptable
acids and aromas (Nielsen, 1995). Depending on the alternative of snack supplementation.
individual chocolate manufacturers recipies the amount of
cocoa mass will be present from 7±15% in milk chocolates
and from 30 > 70% in dark chocolates. Chocolate craving
In addition to these well known ingredients it has A patient coming to an appointment in our obesity unit
recently been discovered that chocolate is a major source describes her reason to choose chocolate as her main source
of dietary copper (Joo & Betts, 1996). In a study of of nourishment in the following way: `I hate cooking, I live
American dietary habits using 3 d dietary records it was on my own, I love chocolate, chocolate makes it quick to
demonstrated that dark chocolate and candy made the prepare a meal, I enjoy this meal thoroughly, eating
highest contribution to the mean daily copper intake chocolate requires little work in the kitchen, no cleaning,
(22% of the estimated safe and adequate daily dietary chocolate eating is satisfying, affordable and gives plea-
intake). The other major contributors were various sure, so why should I not live on chocolate?'
chocolate-containing foods and drinks. Although craving is a common occurrence the literature
Recently Waterhouse et al (1996) quanti®ed the exploring the basis for such cravings is scarce. Chocolate is
amounts of antioxidants in chocolate. Flavonoid phenolics the most commonly craved substance in the United States
in chocolates prevent the randi®cation of the fat in choco- (Weingarten & Elston, 1991). It is not clear whether the
late (a quality which actually made it possible to use craving can be attributed to a pharmacological effect of
chocolate as an important source of energy for soldiers chocolate compounds such as phenylethylamine or magne-
during heavy combat). Cocoa powder was found to contain sium, or whether sensory properties are more important.
20 mg of total phenol gallic acid equivalent per gram. In Since a pre-menstrual desire for chocolate has been
terms of consumption patterns this means that a 40 g demonstrated (Tomelleri & Grunewals, 1987; Rozin et al,
chocolate bar contains the same amount total phenol as a 1991; Buffenstein et al, 1995) it seems reasonable to
glass of red wine. The authors conclude that if dietary believe that there is a physiological or hormonal basis for
phenolics are active also in vivo as antioxidants chocolate this craving. Michener & Rozin (1994) speculate along
provides a signi®cant portion of such dietary antioxidants. these lines and have set up a clinical research protocol
based on the predictions shown in Table 2. By breaking
down chocolate into its components it was possible to
Clinical observations
isolate the sensory, nutritive and pharmacological compo-
There is no doubt that chocolate products are high in nents from each other together with a placebo. This study
energy, most of which comes from saturated fats and suggested that there was no role for the pharmacological
sugar. However, since a signi®cant proportion of the effects in the satisfaction of chocolate craving but a certain
triglycerides in chocolate originates from stearic acid, it role for aroma independent of sweetness, texture and
has been questioned whether chocolate consumption has energy.
any negative metabolic effects apart from the energy Chocolate craving is a strange phenomenon which is
contribution. Most dieticians will tend to recommend still poorly understood. It has previously been confusedChocolateÐdivine food
S RoÈssner
344
Table 2 Theories of chocolate craving and their predictions (Michener and Rozin, 1994)
Theory Milk choc. White choc. Cocoa caps. Placebo White choc. Empty
cocoa caps.
Sensory 0 0 0
Nutritive
Calories 0 0 0
Magnesium 0 0 0
Pharmacological 0 0 0
Result 0 0 0
full effect; partial effect; 0 no effect.
with the term carbohydrate craving (Wurtman, 1987) but it feelings of guilt or relaxation. These authors conclude that
is obvious that when subjects reporting craving are inter- although chocolate provides initial pleasure such pleasure
viewed about what they crave for, it is chocolate rather than is short-lived and soon accompanied by feelings of guilt.
pure sugar that may cause them to leave home at midnight
in search of this desirable food. The association of choco-
Other clinical complications
late craving has ben compared with that of certain drugs
induced psychotic situations, suggesting that pharmacolo- Chocolate has been said to provoke various allergic reac-
gically active substances could be involved. Schifano & tions (Fries, 1978). However, in a critical analysis, Fries
Magni (1994) have described seven subjects with a history concludes that the evidence is generally weak. Other
of drug abuse of MDMA (`ecstasy'). These six young men medical problems attributed to chocolate include pruritus,
and one woman describe a distinct pattern: after having rashes, rhinorrea and asthma (Ghosh, 1977; Fries, 1978;
given up the MDMA, a craving for chocolate developed Wilson, 1985). Further medical complications include acne,
with an intake of up to 2000 calories of chocolate candy per childhood hyperactivity, migraine and irritable bowel
eating episode. Sometimes these were described as binges, symptoms (Kaplan et al, 1989; Grant, 1979; Friedman,
sometimes not. The typical pattern was an episode of 1989). Since the methylxanthines in cocoa can relax the
chocolate craving about once a week with an intake of lower esophageal sphincter re¯ux esophagitis has been
about 1000±1500 calories per episode. In most cases a reported (Murphy & Castel, 1988).
weight loss was observed of up to 14 kg before the On the other hand chocolate has been described as an
development of the craving. The authors conclude that all interesting functional food by Kurihara, who reported that
seven MDMA abusers exhibit striking changes in appetite chocolate products, preventing dental decay, have been
and food preferences which could be explained by a developed in Japan (Kurihara, 1991).
decreased central 5-hydroxytryptamin functioning. They
speculate that chocolate which contains phenylethylamine
Miscellaneous about chocolate
with amphetamine-like properties and the caffeine-like
substance teobromin could be useful in counteracting the Deeply entrenched in obstetric and midwifery folklore is
effects o MDMA withdrawal. the hypothesis that the weight of candy gifts is proportional
These observations are brought forward by the DiMarzo to the birth weight of the newborn. So far this hypothesis
et al (1996) and DiTomaso et al (1996), demonstrating a has never been scienti®cally tested until Nordin (1993)
novel group of pharmacological constituents of chocolate. conducted a prospective study of postpartum candy gift net
Anandamide is a brain lipid which binds to cannabinoid weight and its correlation with birth weight. Thirty-nine
receptors with high af®nity and resembles the psychoactive chocolate gifts were recorded during the study period
effects of cannabinoid drugs. The authors sampled cocoa during a time period when 1491 infants were delivered.
powder or chocolate and demonstrated that these products The box candy net weights ranged from 200±1200 g, the
contain three unsaturated N-acylethanolamines that could birth weights from 2260±4926 g. However, the coef®cient
act as cannabinoid mimics either directly by activating the of correlation between candy and birth weights was only
corresponding receptors or indirectly by increasing the 0.15 (P 0.2). The author assumes that socioeconomic and
anandamide levels. Thus it is possible that the euphoria prematurity-related factors were responsible for the poor
described by many chocolate cravers could be attributed to candy giving. Possibly parents of high birth weight infants
the fact that chocolate products contain substances which are themselves overweight or obese and ®nd it impossible
resemble brain cannabinoids in their action. to express their gratitude with a chocolate box of corre-
Hetherington & Macdiarmid (1995) have analysed the sponding signi®cant proportions. The design of this study
response of chocolate overeaters to different presentations could have been ¯awed by the fact that rumours spread in
of chocolate and found that these subjects exhibit repro- the hospital that weight data would be used retrospectively
ducible changes in appetite associated variables, when to test the separate hypothesis that midwife waist measure-
exposed to chocolate in different forms. These authors ment would be directly proportional to the net weight of the
suggest that chocolate overeating individuals can provide boxed candy. This was expected to result in severe under-
information also about other aberrant eating behaviours. reporting.
In a further study of chocolate addicts Macdiarmid & Rakatansky (1995), disturbed by the report that choco-
Hetherington (1995) studied twenty self-identi®ed addicts late craving could be cured by bupropion (Michell et al,
together with matched controls. As expected, the addicts 1989), suggests that such a drug might be detrimental to
reported a larger amount of chocolate consumption that health and happiness. If chocolate craving is cured, what
controls but also that eating chocolate did not improve would the consequences be? Deep depression, a baby boomChocolateÐdivine food
S RoÈssner
345
when sex replaces chocolate craving or other unwanted dairy butter, and milk chocolate on the plasma lipids of young men.
consequences of approaches to compensate for the choco- Metabolism 42, 121±129.
Kris-Etherton PM, Derr JA, Mustad VA, Seligson FH & Pearson TA
late loss? (1994). Effects of milk chocolate bar per day substituted for a high-
Chocolate addiction is a documented problem (Max, carbohydrate snack in young men on an NCEP/AHA Step 1 Diet. Am. J.
1989). A very personal testimony came from Doctor Clin. Nutr. 60 (suppl 6), 1037S±1042S.
Patterson (1993) who eloquently has described his life as Kurihara K (1991). In functional foods. Nutek Report 1992 68, 42.
Macdiarmid JI & Hetherington MM (1995). Mood modulation by food: An
a chocoholic and revealed that chocolate made it possible exploration of affect and cravings in `chocolate addicts'. Br. J. Clin.
for him to pass his exams or overcome low spirits. His Psychol. 34, 129±138.
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chocolate milk eventually served as a form of aversion netics of aspargus eaters, and the arithmetic of freedom. Trends
therapy and changing his addiction from chocolate to . . . Pharmacol. Sci. 10, 390±393.
Michell GE, Mebane AH & Billings CD (1994). Pharmacological versus
hot buttered popcorn. sensory factors in the satiation of chocolate craving. Physiol. Behav. 56,
419±422.
Morgan J (1994). Chocolate: a ¯avor and texture unlike any other. Am. J.
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