New scientific research sheds light on why Thais and people worldwide may reach for high-calorie snacks during periods of uncertainty: it is rooted in an ancient survival response to potential food shortages. The study, recently published in the journal Food Quality and Preference, provides experimental evidence that anticipated food scarcity powerfully shapes visual attention and cravings for junk food—a dynamic amplified by current global anxieties, economic turbulence, and pandemic aftershocks (PsyPost).
The drive to consume energy-dense foods during uncertain times goes beyond willpower or cultural trends, the researchers argue. It may be an evolutionary legacy honed over millennia, when periods of famine or resource unpredictability forced human ancestors to seek rich-calorie foods for survival. Fast forward to today’s unstable contexts—economic crises, natural disasters, or even local job insecurity—and the same deep-rooted instinct continues to operate, regardless of modern abundance.
The new research, headed by an assistant professor of psychology at Texas A&M International University, and colleagues from the Evolutionary Visual Lab, adds new dimensions to this theory by directly tracking visual responses to food images using eye-tracking technology. Unlike earlier studies relying mainly on questionnaires or self-report, this experiment explored the unfiltered, automatic fascination people have for certain foods under different psychological conditions.
In the study, 142 university students, predominantly women, were divided into groups and “primed” with different scenarios: one group imagined living in an economically stable, resource-rich world; a second group was induced to think of a context fraught with economic instability—such as sudden job losses and foreclosures; a third was primed for violent, dangerous environments involving crime and personal threat. Following these mental exercises, participants viewed paired photos—one high-calorie, one low-calorie—while researchers recorded how quickly and for how long their eyes landed on various foods.
Across all groups, high-calorie foods were visually prioritized: participants fixated on them faster and looked at them longer. Not only did they find these foods more desirable overall, but this pattern held true even after accounting for momentary hunger or socioeconomic background. However, a crucial layer emerged. For people who personally anticipated food scarcity in the future—a psychological belief measured by survey—environmental “priming” with economic uncertainty turbocharged their cravings for calorie-dense food even further, both in gaze duration and in subjective desirability ratings.
By contrast, for those in the “safe” scenario, higher anticipated food scarcity slightly increased their interest in low-calorie options, suggesting that environments signaling resource plenty can dampen the urge for rich foods. Interestingly, violent or crime-focused priming did not have the same effect, indicating that not all forms of anxiety or stress influence eating in the same ways.
As explained by the head researcher, “Evolutionary perspectives on eating behavior suggest that humans have always faced harsh environments, and prioritizing energy-dense foods is a solution to a recurring adaptive problem of food insecurity.” The study’s lead author told PsyPost, “We did find that when primed with cues of safety, anticipated food scarcity was associated with higher desirability ratings for low-caloric compared to high-caloric foods. Safety cues may prime individuals with availability of resources, which in turn, limits the need for energy-dense food.”
This research aligns with the so-called “insurance hypothesis,” proposing that when future food supply feels insecure, people subconsciously “insure” themselves by seeking energy reserves immediately, even when food is currently available. It is also consistent with “life history theory,” which in evolutionary biology explains how organisms—including humans—adapt their behaviors to environmental unpredictability, often prioritizing immediate rewards over long-term gains in tough times (Wikipedia: Life History Theory).
Thai nutritionists and psychologists have observed similar patterns locally. Thai society, with its rapid urbanization and periodic economic shocks—such as the 1997 Asian financial crisis and, more recently, pandemic-driven job losses—often experiences elevated rates of stress eating and junk food consumption in times of national hardship. A public health official at Thailand’s Ministry of Public Health, notes: “There is a clear rise in emotional eating during periods of national uncertainty, which tends to manifest as increased purchase and consumption of sugary, salty, and fatty snacks.” This mirrors the study’s conclusions: both real deprivation and simply perceiving scarcity can trigger a deep-rooted drive for junk food.
Historically, Thailand’s relationship with food blends the abundance of fresh, natural ingredients—evident in traditional diets rich in rice, vegetables, and lean proteins—with the growing influence of processed snacks. High-calorie Western and local comfort foods have become particularly prominent in urban centers like Bangkok and Chiang Mai, especially among young adults and students (Bangkok Post). The study’s use of a predominantly young, university-based sample—mirroring much of Thailand’s highly urbanized youth—suggests the findings are highly relevant to current Thai dietary realities.
Critically, the research cautions that these automatic patterns of behavior are not easily countered with willpower alone. Even when hunger or current economic status are controlled for, mere exposure to messages or images conveying resource scarcity is enough to tip the balance toward unhealthy choices. For Thailand, where food insecurity and obesity coexist in complex ways—especially in rural areas affected by drought or flood—this interplay of ancient psychology and modern media messaging must be carefully considered in public health strategy.
Future developments may see researchers enhance ecological validity by tracking eye movements in real-world settings, such as markets, street food stalls, or convenience stores—environments highly familiar to Thai people. Wearable technology could, for instance, capture how people make daily food choices when exposed to advertising or news about economic hardships. The lead study author has indicated interest in further studies examining how intrasexual competition or “same-sex competition cues” might affect eating and food choice, hinting at the role social comparison may play in dietary decisions.
With Thailand’s ongoing struggles with rising obesity and type 2 diabetes rates, the findings provide a timely warning: in uncertain times—from household financial worries to national disruptions—subconscious evolutionary drives may override health intentions. Recognizing these triggers can help Thai policymakers design better interventions, such as tailored public messaging and targeted food assistance for the most vulnerable.
For Thai readers, the practical message is to remain aware of how news, social media, and daily anxieties about the economy—or even subtle cues in one’s environment—may be fueling cravings for unhealthy food. Practicing mindful eating, stocking up on healthy snacks, seeking emotional support, and limiting exposure to negative news can serve as practical buffers. Community leaders and government agencies should incorporate an understanding of these psychological drivers into nutritional education campaigns, especially in schools and workplaces.
Ultimately, by acknowledging the powerful evolutionary forces shaping our modern cravings, Thai society can develop more compassionate, culturally sensitive strategies to promote health, especially in turbulent times.
Sources:
PsyPost: An ancient survival instinct may explain why we crave junk food during uncertain times
Wikipedia: Life History Theory
Bangkok Post: Thais eat fast food most in ASEAN, study says