Cognitive Behavioral Nutrition in the Lab

At Eastern Kentucky University (EKU) we are examining an array of factors associated with eating. Studies involve standard nutrition protocols, as well as those involving standard social / cognitive / behavioral examinations of eating. We are interested in physiological and  psychological mechanisms and their interactions.

Cognitive Behavioral Nutrition

After my first meeting with Geza Bruckner, University of Kentucky Professor & Researcher, in 2009 my thoughts about eating changed. Bruckner introduced me to research showing factors other than those commonly discussed by nutritionists may have a large impact on eating. A wide range of factors contribute to eating. After an extensive literature search it became apparent to me that the standard paradigm for the study of nutrition was incomplete, and needed expansion. The term “cognitive behavioral nutrition” was coined by myself and colleagues in 2012. CBN is the interface between nutritional science and social / behavioral science. CBN involves the development of comprehensive eating plans- nutritional aspects, learning mechanisms and the myriad of factors driving food consumption. It is important to point out that CBN is the term myself and colleagues use in describing a protocol that includes the essentials I have just mentioned.  Others may follow the principles underpinning CBN, but not refer to those principles as being those of CBN. That is fine; in fact, I suspect the majority aren’t referring to CBN. At this point, it isn’t a widely used term. In addition to standard nutrition recommendations, CBN addresses the home food environment and suggests how the holistic food environment can be structured to make it more conducive to nutritious eating. Structuring the food environment in the appropriate way makes it easier to eat nutritious foods, and less likely to consume food higher in cals…, and lower in nutritional value. Eating nutritious foods doesn’t have to be hard -cognitively draining (right environment less thinking required). Keith Stanovich, cognitive scientist, points out humans are cognitive misers; they don’t like to think hard. It follows that an environment that is conducive to nutritious eating is an environment where eating  requires minimal cognitive effort.

Although in the early stages of development, CBN is already impacting how people view eating and how they design nutrition plans. As an example, one of my colleagues from India informed me that by using principles key to CBN a couple of athletes he works with are better able to manage their eating; they also had a much easier time making weight for a recent competition. I receive a lot of questions, via e-mail, regarding CBN. I include CBN lectures in the psychology courses I teach, and I have spoken about the topic in various gyms and as part of a graduate program in Clinical Nutrition at the University of Kentucky. In the near future expect CBN certification programs and maybe other educational programs.

Environmental factors influence consumption norms by subtly suggesting an appropriate, or normal amount to consume or use. People often under estimate the amount of calories consumed, and environmental factors may make calorie counting more difficult. Package size, distracting stimuli, food type, and meal size can have a negative impact on calorie monitoring. The “health halo effect” is a primary factor associated with food type, and a factor influencing why consuming  nutritious foods may lead to over eating. People may feel that the consumption of a healthy food compensates for the less healthy side items, drinks, or additives they consume along with the healthy food. As an example, individuals may eat a low calorie sub, but in addition eat high calories additives (mayonnaise) and add a dessert to the meal. Calories matter. It is possible to consume excessive calories while eating nutritious foods of various sorts.

The following three abstracts represent studies conducted at Eastern Kentucky University. Additional studies and review papers are in the process.

Studies

Abstract (Hale & Varakin, 2016)

“Some researchers suggest we may not be aware of how environmental factors, such as variety, influence eating behaviors (Vartanian, Herman, & Wansink, 2008; Wansink, 2004). However, in studies examining external factors, systematic measures of awareness are often lacking. In the majority of studies on eating behavior, awareness has not been explored systematically, and in some cases, it has been completely ignored (Brunstrom, 2004). In the current study we investigated whether or not participants would eat more M&M’s from a bowl containing a single color versus a bowl containing a variety of colors. We were also interested in whether or not people who eat more M&M’s from the multicolor bowl would indicate they ate more due to variety. The results showed participants ate more M&M’s from the multi-color bowl than the single-color bowl. Importantly, participants who ate more from the multicolor bowl were more likely to mention variety as a reason for the increased consumption than those who did not eat more from the multicolor bowl. The results suggest there is a relationship between actual consumption and people’s reports of consumption.”

The results suggest there is a relationship between actual consumption and people’s reports of consumption. Participants who ate more from the multi-color bowl of M&M’s were more likely to mention variety as a reason for consumption choice than participants who did not eat more from the multi-color bowl. This is consistent with the idea that participants might be aware of the influence variety of food has on food consumption. The study has limitations, and further research needs to be conducted. The study does not rule out the idea that people are unaware of how other external factors influence food consumption. The study cannot specify whether awareness of variety’s influence was a cause or a consequence of eating. It is possible, for example, that participants only realized they had eaten more M&Ms from the multi-color bowl after they had started to do so. Even if this is the case, it is important to realize that the questions participants answered were carefully worded to avoid prompting participants to think about color variety – the bowls were no longer in sight, and the questions didn’t mention anything about color. Despite these limitations, the current results are important in demonstrating that some people are not completely unaware of at least one external factor’s relationship with food consumption. We are not suggesting that people are always aware of why they are eating what they are eating. However, the current results do not support the strong claim that people are almost always unaware of how external factors influence food consumption.

Abstract (Hale, 2012)

“The purpose of the present experiment was to examine how expectations influence cracker ratings on a scale of likeability. A large body of research shows that expectations affect food experiences (Wansink, 2004; Eertmans, Baeyens & Van den Bergh, 2001; Kahkonen & Tuorila, 1998).  Participants were not aware that the primary interest of the study was how expectations influence cracker ratings.  Participants were assigned to either a positive expectation group or a neutral expectation group. Participants in the positive expectation group received a positive verbal cue indicating that the crackers had recently been rated high in a national taste test.  The neutral expectation group did not receive the information concerning the national taste test.   Participants were administered critical thinking tasks while consuming crackers.  It was hypothesized that those in the positive expectation group would rate the crackers higher than those in the neutral expectation group.  The results of the study did not support the hypothesis.  There was no difference in how the groups rated the crackers.”  Note- the last sentence would be better worded as – There was no statistically significant difference in how the groups rated the crackers. That is stat…signif..in the context of standard frequentist model of NHST.  More about NHST   I didn’t go into the limitations and misconceptions regarding NHST; that is for a different article.

The findings in this study suggest that positive suggestions do not always lead to food liking that is significantly different than neutral (no suggestions).   One possibility for explaining this finding is that participants in the positive expectation group actually did not have a positive expectation regarding the flavor of the crackers.  Maybe the information about the taste test that was intended to induce a positive expectation did not work.  It is possible that the participants didn’t notice the part of the message that suggested the cookies were rated high on a national taste test – “These crackers are a new brand that was recently tested in a National taste test.  The crackers were rated very high on the taste test.” Another possibility for explaining the outcome of the study is the sensory properties of the food were inconsistent with the expectations.  That is, participants in the positive expectation group expected the crackers to have a good flavor, but their expectations were disconfirmed when eating the crackers. A stronger manipulation could have possibly led to a stronger expectation, which may have influenced the outcome. A larger sample was needed, with the effect size we got d = .39 (approaching moderate size) , to detect stat…signif… This was revealed in a power analysis following the study. The small time frame may have influenced the outcome. The type of food used in the study may place limitations on the outcome.  Positive expectations may be hard to induce for a neutral food such as crackers.

Abstract (Hale & Lawson, 2012)

“This study examined caffeine’s effect on sustained selective attention.  It was hypothesized  that participants receiving a moderate dose of caffeine (200 mgs) would have score higher accuracy rates, as measured by a visual conjunction search task, than those receiving placebo.  It was also hypothesized that participants receiving a moderate dose of caffeine would have faster response times, as measured by a visual conjunction search task, than those receiving placebo. Before participating in the study all participants reported that they had no conditions that would prevent them from being part of the study. Participants were randomly assigned to either the caffeine group (n = 10) or placebo group (n = 10).  The results of the study did not support the hypotheses.”

Past studies have demonstrated that moderate doses of caffeine have a positive effect on sustained attention (Trayambak et al., 2009) and selective attention (Kennemans & Verbaten, 1998).  The task used in this study was slightly different than those used in the past. The task was a visual selection task that required sustained attention. Participants were asked to abstain from caffeine intake for at 4 hours prior to the study.  We aren’t sure that the participants followed this protocol; a manipulation check wasn’t used.  In one study in order to ensure compliance with the caffeine fasting protocol participants were required to provide saliva samples before engaging in study (Brunye et al., 2010).  A similar requirement in the present study may have strengthened the manipulation. Past studies have demonstrated that moderate doses of caffeine have a positive effect on sustained attention (Trayambak et al., 2009) and selective attention (Kennemans & Verbaten, 1998).  The task used in this study was slightly different than those used in the past. The task was a visual selection task that required sustained attention. It has been suggested that a 12 hour caffeine fast is required to sufficiently attenuate the effects of earlier caffeine consumption (Culm-Merked, et al, 2005).  Another limitation in this study is sample size.  A large effect size was predicted, so the sample we used was relatively small.  Possibly, with a larger sample the results could differ. Future studies should investigate sustained selective attention using a larger sample than the one used in this study.   In addition, to ensure a strong manipulation studies should inform participants that they should abstain from caffeine consumption for at least 12 hours prior to the study.  Informing students that there will be either a blood sample or saliva sample taken before participating in study may lead to higher levels of adherence to suggested protocol.

Full papers available upon request

Jamie Hale