Eating energy-dense foods when one is not hungry is a contributor to overweight and obesity, which are risk factors for a range of cancers. Excessive eating of a subset of these foods, such as red meat or foods with a high glycemic index, is an additional risk factor for cancer, separate from overweight and obesity. We refer to foods that are linked to cancer through either or both routes as cancer-promoting foods. The goal of this project is to reduce cancer risk by improving cognitive self-regulation of cravings for cancer-promoting foods. We focus on craving of cancer-promoting foods as one proximal determinant of their consumption. Craving consists of a subjective sense of wanting to eat a food, a motivation to seek out the food, and recurrent or intrusive thoughts related to the food. Considerable research shows that craving is a strong predictor of eating, even in the absence of hunger. Thus, enhancing a simple, low-cost and easily disseminated tool to reduce craving for cancer-promoting foods would advance cancer prevention and related research. Studies from affective science and social neuroscience have identified cognitive self-regulation strategies that are effective in reducing craving and their associated neural systems. This work has focused mostly on craving for other appetitive stimuli (e.g., drug cues), and has only begun to study regulation of food craving. Recent results from our laboratory validated four strategies that are effective in reducing cravings for energy-dense foods. This work relies upon self-reports of craving, which provide an empirical starting point but do not demonstrate the validity of the strategies on their own. Thus, the goals of the proposed project are to provide additional support for the effectiveness of cognitive self-regulation of food cravings using other measures beyond self-report, and to validate a theoretically grounded means to further increase the efficacy of those strategies-strategy choice. These goals will be accomplished in the context of a single study with two sessions. First, participants will be randomly assigned to choose their regulation strategy or to have one selected for them. In Session 1, their self-reported cravings and neural responses will be recorded while they alternately view images of energy- dense foods and regulate their responses to those foods. These data will be used to examine the effects of food regulation on neural activation and self-reports of craving, and to compare the effect of strategy choice on those measures. In Session 2, participants will visit our behavioral laboratory three days following Session 1 for a session in which their actual intake of energy-dense food will be measured in a naturalistic and unobtrusive manner. The difference in energy-dense food intake between the two groups will provide a behavioral measure of the efficacy of strategy choice on eating. Also, brain activity during food cue reactivity and regulation from Session 1 will be used to predict intake during Session 2. Psychological theory and previous neuroscience data suggest that neural activity, particularly in the medial prefrontal cortex, might explain variance in energy-dense food intake above and beyond self-report, and might mediate the effect of strategy choice on intake.
Excessive eating of energy-dense foods is a risk factor for a range of cancers. There is strong evidence that reducing craving for these kinds of foods would reduce their consumption and its related cancer risks, but there are currently few tools available that have been proven to reduce craving for cancer-promoting foods. The project seeks to increase the efficacy of one such tool-cognitive self-regulation-based on theory and data from psychology and neuroscience suggesting that the act of choosing a self-regulation strategy (versus being assigned to one) further increases the potency of that strategy to reduce cravings for cancer-promoting foods.