C ARBOHYDRATE C RAVINGS

13.3.1 C ARBOHYDRATE C RAVINGS

Cravings, an intense desire or longing for a particular substance, 49 are hypothetical constructs that frequently appear in the addictions literature. This is a term that has also found its way into the literature on food and is typically used to describe in intense desire or urge to seek out and consume particular foods. 50,51 Up to 97% of

women and 68% of men have reported cravings for specific foods. 52 However, the prevalence of food cravings depends on the definition used, and as the definition becomes more stringent, the percentage of identified food cravers can decline to as

little as 4%. 53 Regardless of how stringent a definition is used, all studies revealed that some individuals experience food cravings. Several studies have investigated factors affecting food cravings, and these studies have identified that a variety of factors, such as age, gender, prior meal consumed, mood, and type of food, affect food cravings. Several studies 50,54 have revealed that food cravings decline with age and that food cravings can be triggered

by the repeated consumption of the same food. 55 Studies have also investigated the type of food craved and repeatedly revealed that sweet foods, such as chocolate, cake, and ice cream, are most frequently craved, followed by starch foods, such as pasta and breads. 53,56 Interestingly, it is women that not only demonstrate more food

cravings, 54 but also more frequently report cravings for sweet foods. 51,56 This craving for sweet foods or, more specifically, foods that are sweet and rich in carbohydrates

led to the origination of the term carbohydrate craving. 57 Since that time, the term carbohydrate craver has been used repeatedly in the literature to refer to individuals expressing an intense desire for sweet carbohydrate-rich foods. This may be an unfortunate use of the term because the foods that are desired by so-called carbo- hydrate cravers contain considerable amounts of fat, and the most frequently craved foods are not just any carbohydrate, but sweet carbohydrate-rich foods that are also fat rich. 40,58

Given that carbohydrate cravers have a desire for sweet carbohydrate- and fat- rich foods, one might assume that these individuals would consume more daily energy than noncarbohydrate cravers. There is some evidence to suggest that this is

not the case. Hill et al. 59 revealed that there was no significant difference in the daily energy consumed of food cravers and food noncravers. While this study focused on food cravers rather than carbohydrate cravers, the most commonly craved food is

sweet carbohydrate- and fat-rich foods, 57 so most of the participants in the study would probably have been carbohydrate cravers. The failure to find a difference

between the energy consumption of cravers and noncravers may be due to the fact

Dietary Carbohydrates as Mood and Performance Modulators

that food cravers consume most of the craved food as snacks 60 rather than at meals and typically in the afternoon or evening. 60 Why is it that the most frequently craved food is a sweet carbohydrate- and fat- rich food? One of the obvious answers is that this is the most pleasant tasting food, 40 so it would be the one that is most rewarding and, therefore, craved. However, carbohydrate cravings (I will continue to use this label to refer to the desire for sweet foods even though it is recognized that the food craved is sweet carbohydrate- and fat-rich foods) seem to occur most frequently during certain mood states, which would suggest that the desire or craving for the carbohydrate food is more than just its pleasant taste. This is not to imply that mood is the only factor contributing to

the experience of carbohydrate cravings, as research 61 has demonstrated that cravings are influenced by many factors, such as environmental cues and thoughts. Mood

seems to be a significant factor contributing to the experience of carbohydrate cravings and is the factor that has been most frequently investigated with respect to

carbohydrate cravings. There are several studies that have demonstrated that carbohydrate cravings are correlated with various indices of emotional distress. Hill et al. 59 has revealed that food cravings are correlated with emotional eating or with an increased appetite stimulated by the presence of a negative mood. This is consistent with studies revealing that many cravers, especially carbohydrate cravers, report that cravings

are associated with feelings of fatigue, especially in women, 60 or being anxious and depressed. 51 Cravings for chocolate are correlated with depression and guilt 62 and a variety of other measures of distress, such as tension/anxiety, confusion, and fatigue. 51 It is especially important to realize that these correlations with measures of a dysphoric mood occur only with carbohydrate cravers. Cravings for other foods, such as protein, are not correlated with dysphoric mood states. 51 The interesting thing about the correlation between carbohydrate cravings and dysphoric mood states is that this occurs primarily with cravers of sweet carbohydrate-rich foods, such as

desserts, and not with non-sweet carbohydrate-rich foods, such as pasta. 51 This relationship between a dysphoric mood state and carbohydrate cravings occurs with about half of all carbohydrate cravers. 51,62

Why should individuals with a dysphoric mood state be motivated to consume sweet carbohydrate-rich foods? The evidence suggests that the sweet carbohydrate- and fat-rich food snacks are consumed for the ameliorative effect that they have on the dysphoric mood state. 51,60 Carbohydrate cravers tend to report feeling anxious, tired, depressed, and hungry prior to consuming the food that they crave, and following the consumption of this food, they report positive moods such as

satisfied, happy, and relaxed. 51 Additionally, experimental studies 63 have demon- strated that the induction of a mood state such as depression results in an increase

in the effort both humans and animals will expend to receive a sweet carbohydrate- and fat-rich reward.

While all studies 62 do not demonstrate an improvement of mood following consumption of a sweet carbohydrate-rich food, and the lifetime experience of a psychiatric diagnosis between cravers and noncravers 56 does not differ, the bulk of the evidence does support the finding of a positive mood-altering effect following consumption of a sweet carbohydrate- and fat-rich snack in carbohydrate cravers.

Functional Food Carbohydrates

Further evidence indicating that consumption of a sweet carbohydrate- and fat-rich snack ameliorates a dysphoric mood comes from studies investigating the effect of

a carbohydrate-rich snack in individuals with a variety of psychiatric diagnoses.