Title: Mood and Chocolate

Key words: cocoa, hysteroid dysphoria, compulsive eating, craving, depression, chocoholic, chocolate addiction

Date: Sept 2000

Category: The Mind

Type: Article

Author: Dr Van Rhijn

Mood And Chocolate.

Introduction

Chocolate, a processed food made from cocoa (Theobroma cacao) seeds and sugar (sucrose) is a significant source of several nutrients, enhanced by its preparation with milk. The average UK annual intake per capita approximates 9 Kg (12 bars/week) and the relation with its consumption and mood will be further discussed.

Chocolate and Mood

The foods and moods inventory (FMI) questionnaire, used to investigate appetite for sweets and chocolate and its relationship to dysphoric mood, revealed that those who reported "self-medicating" with sweets or chocolate were more likely to have personality traits associated with hysteroid dysphoria, and atypical depressive syndrome. Women were significantly more inclined to eat compulsively and had a greater appetite for sweets and chocolate¹. Other surveys confirmed the finding that chocolate was highly liked and probably the most craved food (49%)² especially by females in the peri-menstrual period, suggesting a link between magnesium as well as a link between negative³ or dysphoric⁴ moods.

An interview and completed battery of questionnaires on food cravings, eating, weight, dieting and depression on individuals who identified themselves as "chocoholics", found the amount of chocolate consumed correlated significantly with disinhibition (lack of control) around chocolate. The "addictive" factor and craving motivation of chocolate was regarded primarily as orosensory⁵ pleasure (hedonic appeal of fat, sugar, taste, texture, and aroma⁶) and cognitive experiences or mood states associated with post-ingestional effects of chocolate. Dieters and secret chocolate eaters experienced negative effects, 'addicts' reported guilt⁷ feelings without mood improvement and also reported a higher degree of aberrant eating⁸. A study, using music-induced states (happiness or sadness), found that chocolate craving and intake (rather than substitute carob) increased in those who heard sad music⁹. Another study found that arousal was rated higher when candidates were exposed to chocolate scent¹⁰.

Possible Physiological Mechanisms

Chocolate provides numerous amino acids, which may have modulatory effects on several mood-modifying neurotransmitters. For example tyrosine, a precursor for endogenous catecholamine (norepinephrine) production. Its concentration is associated with several mood disorders, and it is also required for melanin production for prevention of seasonal affective disorder. Tryptophan, a serotonin precursor and major neurotransmitter associated with depression, alleviates bipolar affective disorders, mania, anxiety, and reduces aggressiveness. Chocolate also contains anandomides (cannabinoid)¹¹, phenylalanine and phenylethylamine (metabolised by MAO-B), a stimulatory neurotransmitter (like amphetamine) responsible for emotions associated with infatuation and love.

Chocolate contains the stimulants caffeine and theobromine, a methylxanthine (like caffeine but weaker) that activates the CNS. It also contains toxic pressor amines, such as tyramine, that cause hypertension (norepinephrine) and result in depression, mood swings and anxiety. Thus prohibiting chocolate (daily consumed by 30% of psychiatric patients) from the diet is essential in patients who are potential candidates for antidepressant treatment with monoamine oxidase inhibitors (MAOIs) in order to prevent tyramine induced hypertensive reactions¹².

It has been suggested that ingestion of excessive carbohydrates increases the ratio of tryptophan:large neutral amino acids¹³, thereby enhancing serotonin^14,15 production and subsequent mood modulation. This reflects self-medication by depressive patients, temporarily relieving vegetative symptoms¹⁶. These theories are disputed, however, as chocolate contains 13% protein that would decrease rather than increase tryptophan uptake¹⁷ and a single chocolate bar does not contain enough ‘drug-like’ substances to produce pharmacological effects¹⁸. Benton concluded the ‘chocolate effect’ is probably due to a release of endorphins, which modulate the intake of sweets and other palpable foods^19,20.

Conclusion

Chocolate has great effects on mood and is craved by those who feel emotionally low. The most likely psychopharmacological mechanism accounting for mood elevation is stimulation and endorphin release, the latter quality shared with all palatable foods. The chemosensory effects suggest that oral gratification is as important as mood elevating nutrients to satisfy chocolate craving.

References

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