Section 1.1: What Drives Our Food Choices?

At first glance, our culinary preferences may seem trivial—either we enjoy a certain food or we don’t, or perhaps we only like it under specific circumstances. However, the reasons behind our likes and dislikes go beyond simple taste buds. While flavor undoubtedly plays a significant role in determining what we choose to eat, it is not the sole influence.

Joanne Cole, a geneticist and assistant professor at the University of Colorado School of Medicine, explains that “the foods we select are largely shaped by environmental factors such as culture, socioeconomic status, and food availability.” This multitude of influences complicates the task of identifying why we favor some foods over others, as well as the role genetics might play in our dietary habits.

Another challenge has been the lack of technology capable of isolating genetic influences from these other factors. Fortunately, advancements in technology now make it possible to explore these connections, and Cole has been quick to seize the opportunity.

Subsection 1.1.1: Recent Breakthroughs in Research

In her research, Cole and her team utilized data from the U.K. Biobank, a comprehensive public biomedical database containing genetic and health information from 500,000 individuals in the UK. This allowed them to conduct a Phenome-wide Association Study (PheWAS), identifying connections between gene variants and various human behaviors, including dietary choices.

In a 2020 study, Cole and her colleagues performed a heritability analysis using this Biobank data, scanning the human genome for areas linked to dietary habits. They identified 814 regions associated with food intake, although only about 5 percent of these genetic factors directly influenced nutritional traits. Despite this, Cole expressed optimism about the findings, stating, “It means these traits are largely environmental, but that doesn’t diminish the significance of the 5 percent.”

By 2023, Cole and her team had further leveraged the U.K. Biobank's rich dataset, which includes detailed health, genetic, and socioeconomic information. This enabled them to analyze specific gene variants and their association with thousands of traits, allowing for the exclusion of indirect correlations linked to other health conditions, such as diabetes.

Cole's team pinpointed 481 genomic regions directly tied to specific food preferences and eating patterns. Notably, they found 287 regions associated with particular foods like alcohol, cheese, fish, fruits, and tea, while 194 regions correlated with overall dietary habits, indicating healthier or less healthy eating patterns.

Cole highlighted that genes related to digestive enzymes, taste receptors, and olfactory receptors significantly impact our diets. She remarked, “In most of our diets, we consume a variety of foods together, so the connections are often intertwined. However, the olfactory receptor genes we identified were exceptionally specific. One was uniquely associated with cheese, while others were specific to fruits, vegetables, and coffee.”

Though these findings have yet to undergo peer review, they were presented at the American Society for Nutrition’s annual conference in July 2023.

Section 1.2: Looking Ahead

While these discoveries are exciting, further research is imperative. Cole believes this initial exploration merely scratches the surface of what’s achievable. With specific genome regions identified, her goal is to delve deeper to uncover which genes are intricately linked to dietary intake. She explains, “I aim to identify genes closely tied to dietary habits without other health conditions interfering, as I hope we can target these genes’ biological pathways. For example, we could modify the flavor compounds that interact with specific receptors to provoke different brain responses, potentially enhancing nutritional adherence to healthier foods.”

In essence, Cole envisions a future where scientists could adjust flavor perceptions—not the actual flavors themselves—to promote healthier eating habits. For instance, if someone has an aversion to broccoli, instead of changing the vegetable's flavor to something more palatable, researchers might eventually find ways to alter genetic pathways so that individuals find broccoli more enjoyable. Cole succinctly asks, “Can we change the perception of flavor through biological understanding?”