# Motivation and emotion/Book/2014/Chocolate and mood

* Multimedia presentation (5 min)
* Overview
* This chapter focuses on the relationship that exists between the consumption of chocolate and its emotional consequences; in particular, whether it can make us happy. The chapter begins with an introduction into the composition of chocolate, and which components of chocolate have been researched to have an implication on one's emotions and mood. Following this, an exploration of various theories of happiness is presented along with a discussion in regards to physiological and biological components and processes that underlie behaviour, and how chocolate interacts with these to induce particular moods and emotions, including happiness. Finally, this chapter focuses on the present day literature into chocolate consumption, and whether it can make people happy, as well as opposing arguments and studies that disprove this notion. This chapter is accompanied by specially drawn diagrams to assist in the understanding of potentially difficult topics, along with useful concept checks to highlight the most important aspects of each section to assist with interactive learning.

## Chocolate
### Composition

Chocolate is a product that is made from cocoa beans, the fruit from a species of tree known as Theobroma cacao L., native to particular regions of the Americas (Rusconi & Conti, 2010). Chocolate is made up from a large variety of ingredients, in addition to products extracted from cocoa beans, such as sugar, lecithin, milk, nuts and fruits (Torres-Moreno, Torrescasana, Salas-Salvado & Blanch, 2015). Additionally, varying amounts of cocoa product in chocolate produces different varieties, such as dark and milk chocolate types, being why dark chocolate has been found to be beneficial for the cardiovascular system, given the variation of fats and chemical composition resulting from the amount of cocoa product that is present (Torres-Moreno et al., 2015).

### Chocolate composition and its relationship with mood

In regards to the composition of chocolate, a number of ingredients and chemical arrangements have been found to have an impact on mood and affective behaviours in humans, and this is summarised nicely in a research paper by Parker, Parker and Brotchie (2013), who seek to assess the current literature and findings in physiology in terms of chocolate consumption and mood (Torres-Moreno et al., 2015). Chocolate is high in energy, carbohydrates and fat, with some products consisting of up to 45% carbohydrates (Torres-Moreno et al., 2015). Carbohydrates in chocolate have been linked to depressive disorders, in that one craves chocolate and its high carbohydrate load in order to increase serotonin levels and, therefore, improve one’s mood (Parker et al., 2006). Flavonols, a type of antioxidant, which are found in high concentrations in dark chocolate, have also been linked to human emotion in that they are attracted to particular receptor sites which results in a relaxed state, just as when benzodiazepines bind to these same sites (Medine as cited in Pase et al., 2013). This indicates the potential for alterations in mood as a result of the consumption of flavanols (Sokolov et al., 2013). Dopamine, a neurotransmitter associated with reward and pleasure, has also been linked to chocolate consumption in that one looks forward to eating chocolate, and receiving the positive consequences which are reinforcing and rewarding, thereby leading to an increase in dopamine levels and a successive positive mood (Parker et al., 2006). This relationship between chocolate and reward fits in with hedonism and desire theories of happiness.

## Happiness

In psychology, there are three primary theories of happiness. Hedonism, desire and objective list theories, and a fourth, authentic happiness theory, that combines the other three. In regards to the topic of chocolate consumption having an influence on one’s happiness, research almost always uses measures based on the hedonism theory of happiness as an indicator for change after chocolate consumption.

### Hedonism theory

According to hedonism theory, perhaps the most favoured of happiness theories amongst psychologists, happiness is an emotion that comprises of two parts: eudaimonia and hedonia (Kringelbach & Berridge, 2009). Hedonia is defined as the feelings of well-being and pleasure that we are consciously aware of; essentially, it is the affective component of happiness or the feelings of pleasure at a given moment (Kringelbach & Berridge, 2009). Eudaimonia, on the other hand, is an individual’s sense of life satisfaction in terms of their sense of life meaning and engagement as a whole (Kringelbach & Berridge, 2009). When assessing an individual’s hedonic and eudaimonic components through self-report techniques, it is often found that scores are generally equal to one another (Kringelbach & Berridge, 2008). In adopting this structure of happiness, happiness can therefore be defined as an elevated composite score of hedonic and eudaimonic ratings. On another take on this theory of happiness, Seligman & Royzman (2003) agree that happiness is marked by a subjective feeling, but go forth to state that in order to have a happy life and be a happy person, maximising pleasurable feelings and minimising negative feelings are defining needs for happiness. While they do not mention eudaimism explicitly, experiencing more positive than negative life events paves the way to feeling a sense of life meaning and fulfilment (Seligman & Royzman, 2003). In all, happiness as according to hedonism theory, is the experience of more positive feelings than negative ones (Kringelbach & Berridge, 2008; Seligman & Royzman, 2003).

### Desire, objective-list and authentic happiness theories

Desire theory states that a state of happiness is a result of getting what you want or desire, in which case these wants and desires are fully subjective (Seligman & Royzman, 2003). This theory also assumes, unlike hedonism theory, that happiness does not depend on one’s desires being positive (Seligman & Royzman, 2003). For example, one may experience a negative affect, but still be considered happy, according to this theory, if s/he is often able to fulfil their desires. Objective list theory assumes that happiness results from achieving items on a list of lifetime goals and accomplishments, such as having love and education, receiving promotions and having children (Seligman & Royzman, 2003). Finally, authentic happiness theory, suggests that there are three types of happiness which incorporates hedonism, desire and objective list theories: pleasant life (hedonism), good life (desire) and meaningful life (objective list) (Seligman & Royzman, 2003). Seligman & Royzman (2003) state that authentic happiness results in satisfying a full life through satisfying all types of happiness.
* Concept check
* Hedonism theory of happiness is the most favoured theory to define what it is. It emphasises that more positive experiences than negative are evident in a happy person.
* Desire theory of happiness suggests that getting what you want leads to happiness; such wants are subjective.
* Objective list theory is broader in that happiness is experienced when an individual achieves experiences and goals in their life that are generally viewed as being a good experience, such as falling in love.
* Authentic happiness incorporates these three theories.

## Chocolate consumption leads to positive affect
### Chocolate consumption and serotonin
#### Serotonin and the chemical imbalance theory

Serotonin, also known as 5-hydroxytruptamine or 5-HT, is a type of neurotransmitter that is found in a number of parts of the body, and in particular, the central nervous system, which includes the brain and spinal cord (Jonassen & Landro, 2014). The serotonin pathway has been implicated in the emotional and motivational aspects of behaviour (Menses & Liy-Salmeron, 2012). Such a relationship became apparent after various theories uncovered correlations between abnormally functioning pathways with psychological disorders such as depression, anxiety and schizophrenia (Jonassen & Landro, 2014; Meneses & Liy-Salmeron, 2012). Additionally, medications such as SSRIs that work on the serotonin pathway imply a relationship between serotonin and emotional behaviours because of the change in emotion and behaviour following administration (Cherek & Lane, 2001).
Chemical imbalance theory is popular in the field of psychopathology, which suggests that disorders such as anxiety, depression and schizophrenia are caused by an imbalance of chemicals and neurotransmitters such as serotonin, in the brain (Deacon & Baird, 2009). Chemical imbalance theory suggests that serotonin is directly related with mood; this is why depressive disorders may develop when serotonin levels become too low(Deacon & Baird, 2009).

#### Chocolate's influence on serotonin pathways

Research has determined that it is not the chocolate itself that results in changes in serotonin levels in the body, but the carbohydrates in the chocolate, and chocolate is particularly high in its carbohydrate load (Benton, 2002; Toress-Moreno et al., 2015) Therefore, when discussing the implications on serotonin levels, the use of the wording chocolate consumption can be used interchangeably with carbohydrate consumption. Benton (2002) notes that carbohydrates are able to increase levels of serotonin because its consumption results in an increased amount of an amino acid called tryptophan also entering the body, an essential ingredient in order to synthesise serotonin (Figure 1). Therefore, when more tryptophan is available to an organism, more serotonin can be produced (Benton, 2002).
In a study on the influence of chocolate on serotonin release, Kim, Lien, Sun, McDermott and Owyang (2000) hypothesised that eating chocolate would help to ease gastrointestinal symptoms, such as heartburn. Researchers found that consuming chocolate lead to a release of serotonin from a specialised cell in the epithelial tissue of the intestines, which lead to activation of serotonin receptors and relaxation of muscles in the gastric system (Figure 1) (Kim et al., 2000). While this is not a demonstration of serotonin and emotion specifically, the study highlights biological mechanisms behind chocolate and serotonin, and that chocolate, and its carbohydrate load, indeed has a role in the release of serotonin (Kim et al., 2000).

#### Serotonergic hypothesis

The basis upon which the serotonergic hypothesis was built acts as further evidence that suggests that carbohydrates elevate serotonin levels. The serotonergic hypothesis is popular amongst researchers today, which circles around the notion that it describes why one self-medicates with chocolate (Parker et al., 2006). The serotonergic hypothesis proposes that those with a serotonin deficiency use chocolate and other high in carbohydrate foods as a means of self-medication, hence a craving for these foods (Parker et al., 2006). The serotonergic hypothesis is behaviourally evident in individuals during a symptomatic experience of their disorder; for example, an individual with generalised anxiety disorder will experience a craving for carbohydrates during an anxiety attack, and then experience an elevation in serotonin following this episode as evident in relevant studies (Ventura, Santander, Torres & Contreras, 2014).
Given serotonin’s relationship with positive and negative affect as according to chemical imbalance theory and other findings from SSRI administration and experimental studies, if chocolate could be a key to increasing serotonin levels, it is essentially also key to increasing the occurrences of positive affect, and therefore happiness in terms of the hedonism theory of happiness.

### Chocolate consumption and dopamine

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#### Dopamine

Dopamine is a neurotransmitter that is primarily involved in maintaining moods and playing a role in cognition and cognitive skills (Zhao et al., 2015). Like serotonin, dopamine is also discussed in the chemical imbalance theory in that excess and depletions of dopamine may lead to mental illness such as schizophrenia and depression (Deacon & Baird, 2009; Zhao et al., 2015). Such occurrence is also supported by research studies and administration of medications on the dopamine pathway (Zhao et al., 2015). Research has not found a direct relationship between chocolate or carbohydrate consumption with altering dopamine levels, but it has instead been implicated in playing a significant role in the reward system of the brain (Wise & Rompre, 1989). Studies have shown that there is a link between consuming pleasant and desired foods and alterations in mood (Wise & Rompre, 1989) (see Figure 2).

#### Chocolate's influence on dopamine pathways

Brain structures involved in emotional and reward expectancies such as the prefrontal cortex and nucleus accumbens are structures that work to anticipate and expect a reward when they consume a pleasurable meal, especially when it is high in carbohydrates and fat, such as chocolate (Angeles-Castellanos, Salgado-Delgado, Rodriguez, Buijs & Escobar, 2008). As a result of this activation of particular brain structures, a change of dopamine release is often experienced; for example, an increase in dopamine will occur when an individual has been rewarded with a delicious piece of chocolate and their experience towards the food has been positive (Angeles-Castellanos et al., 2008). This hypothesis is assumed to be generalised to foods that are preferred by the individual, rather than an experience that is only met when consuming chocolate (Parker et al., 2006). This relationship between food, dopamine and elevated mood takes the desire theory of happiness on board, in that, positive experience and an elevated mood as a result of reward and dopamine release is very subjective, and may not illicit the same responses in those who see consuming chocolate as a negative experience (Seligman & Royzman, 2003). This effectively means that happiness levels, in terms of dopamine effects, will only rise in those who like chocolate, and not because there is a particular substrate in chocolate that induces happiness. Following the experience of reward from consuming a desired food, as described, dopamine levels will increase. This is expected as according to the chemical imbalance theory; an increased level of dopamine, as a result of reward from chocolate consumption, elevates mood, evident from studies that demonstrate that schizophrenia is related to high dopamine, while depression to low dopamine (Deacon & Baird, 2009; Zhao et al., 2015).
Essentially, when speaking about the effects on dopamine in the brain, if one was to find eating chocolate a positive experience, the reward of consuming the chocolate and the successive increase in dopamine levels is presumed to lead to an increase in positive affect, and an increase in happiness levels as according to both the hedonic and desire theories of happiness (Seligman & Royzman, 2003; Zhao et al., 2015).

### Flavonols and emotion

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#### Flavonols

Flavonols are a type of polyphenols, which are essentially a group of compounds that are necessary in the human diet and are found in plants (Pase et al., 2013). Cocoa has a large amount of polyphenols, including flavanols, in it, with dark chocolate having a higher amount of cocoa than other varities of chocolate, thus the notion that dark chocolate is good for you (Pase et al., 2013; Sokolov et al., 2013)

#### Flavonol's influence on emotion

Evidence suggests that chocolate consumption has been implicated in emotional modification because of the presence of flavanols in the chocolate (Pase et al., 2013; Sokolov et al., 2013). Medina (as cited in Pase et al., 2013) stated that a number of studies have found that polyphenols such as flavonols are attracted to GABAa receptors (adenosine and benzodiazepine receptors), and just like when benzodiazepines bind with these receptors, flavonols induce a calming effect and reduced anxiety when they bind with GABAa receptors, improving the emotional state of the individual (Medine as cited in Pase et al., 2013). Research into the interaction between flavonols and emotion is seldom researched, so few pieces of literature pertaining to the topic exist.
* Concept check
* Serotonin is a neurotransmitter that plays a role in emotion and cognition evident from correlation studies and SSRI treatment.
* Chemical imbalance theory suggests that depressed moods and psychiatric conditions result from imbalances in neurotransmitter levels; low serotonin and dopamine for sad and depressed mood.
* Carbohydrates in chocolate help the synthesis of serotonin, and therefore an elevated mood occurs. Happiness according to hedonic theory.
* Dopamine plays a role in the reward system of the brain. On receipt of award, dopamine levels increase and positive affect results (too much dopamine leads to feelings of a high such as in schizophrenia).
* Dopamine impacts mood subjectively; that is, one must find eating chocolate a positive experience in order to feel the elevated mood.
* Cocoa contains a type of compound called flavonols, which have been researched to bind to the same receptor sites that benzodiazepines bind to, leading to the same relaxing feelings.
* In this section, the chapter introduced three ways in which chocolate and its components have been researched to be involved in the alteration in mood, specifically as a positive affect. This gives a sense of understanding behind why in a physiological sense, chocolate has been researched to make a person happy, as we will discuss in the next section.

## Can chocolate make us happy?

Knowing the impact that components of chocolate have on physiological processes such as on serotonin pathway and mood, studies have been performed to support these biological theories and findings in that chocolate consumption can make us feel hedonically happy, in addition to causing positive affect as described above. All of the studies that are discussed in this section, measure happiness in terms of the hedonic theory of happiness.

### Short term happiness

Many studies report findings that suggest that the consequences of induced happiness are only short lived. Despite not referring to happiness specifically, but instead mood, a study by Macht & Mueller (2007) found that chocolate did indeed induce feelings of increased mood, but these elevations in positive affect were, on average, gone after three minutes post chocolate consumption. In another study, happiness was specifically considered by Macht and Dettmer (2006) who explored how mood changed as a result of eating chocolate as many would do on an everyday basis meaning that there were no specially induced conditions that one would not experience in their home life. Happiness was measured in terms of the hedonic theory to happiness; that is, subjective feelings of happiness after eating a chocolate bar (Macht & Dettmer, 2006). Amongst other foods that were tested, chocolate was the best food to have one feel happy.
Another study by Abdul-Aziz, Al-Mulwallad and Kader-Mansour (2011) assessed how the effects of chocolate consumption impacted non-clinical depressive symptoms in a sample of nearly 300 female university students. Greater consumption of chocolate, whether it be at once or over a period of time, was implicated as being better for mood improvement than smaller amounts of chocolate, given their findings that chocolate in general was able to have one feel happier (Abdul-Aziz et al., 2011). In other studies such as in Pase et al. (2013), similar results were uncovered despite it not being a direct report of happiness, but instead, a better mood as a result of chocolate consumption.
Finally, in a study by Radin, Hayssen & Walsh (2007), researchers aimed to find whether the belief that chocolate will help elevate mood, actually elevate mood. While researchers found that mood elevated in those consuming chocolate, it was elevated more so in those who believe it would make them feel happy (Radin et al., 2007). The take home message from this study, and evidence from the others, is that if one wishes to improve their happiness through chocolate, one must believe that it actually will make them happy, and perhaps should not read the final section in this chapter pertaining to confounding evidence that chocolate indeed does makes us happy.

### Long term happiness

At present, it was not evident that any studies exist that look into the long term effect of consuming chocolate on food, or consuming chocolate over an extended period of time. Studies by Pase et al. (2013) and Abdul-Aziz (2011) show that when chocolate and its polyphenols and flavonols are administered over an extended period of time (up to 30 days in one study), greater increases in positive affect were evident in the gained data; however, results were not explicitly in regards to happiness, but measures of hedonic mood were still performed. Despite the studies that exist only on extended administrations rather than long term effects of a single dosage, Rodrigues-Silva (2012) suggests that the results from studies that assess short term effects cannot be used to assume the long term effects, given antidepressants still work despite after about a month or so with no short term effects, and that antidepressants work only when administration occurs over an extended period of time. Rodrigues-Silva (2012) is essentially telling their readers that first appearances of a drug, or chocolate’s workings, can be deceiving, meaning experimental studies will need to be carried out to determine exact long-term effects, rather than relying on assumptions.

### When chocolate doesn't make us happy

Few studies have reported findings that confound many other studies in reporting that happiness does not improve happiness, or induce feelings of sadness. Despite the positive findings in Macht and Dettmer’s (2006) study that was described earlier, researchers also found that for some, feelings of guilt were present instead of positive affect, and suggested this resulted from negative cognitions about chocolate, versus reward effects in the other participants. As in Macht and Dettmer’s (2006) study, McDiarmid and Hetherington (1995) also suggested that when one experienced feelings of guilt in their study, positive affect is seldom experienced and instead, experiences of negative affect significantly increased. In both cases, chocolate resulted in a decrease in happiness in a number of participants, confounding the results from other studies that suggest chocolate causes happiness (Macht & Dettmer, 2006; McDiarmid & Hetherington, 1995).

## Conclusion

This chapter has discussed the relationship that is held between chocolate and the emotion that is happiness. Taking a physiological perspective, it is clear through research that chocolate has an impact on serotonin and dopamine pathways, and flavonols in chocolate on brain receptors, which leads to a change in mood; specifically, a more positive affect. There appears to be many studies that suggest that chocolate has the capacity to change one’s mood, and even make someone happy, particularly for the short-term. Future studies are required to determine the exact efficacy of improving happiness using chocolate, and to determine the longevity of its effects as they have been disregarded in many pieces of the literature available. Overall, however, it is evident that chocolate and its properties have an impact both on affect and happiness specifically, and is supported by numerous experiments and studies focusing on the physiological underpinnings of this relationship. So perhaps, yes, chocolate can indeed make us happy.