Color, Sentiment, and Structure: A Comparative Study of Instagram Marketing Across Economies

Instagram has become a key platform for global food brands to engage diverse audiences through visual storytelling. While previous research emphasizes content-based strategies, this study bridges the gap between content and context by examining how aesthetic elements -- such as dominant image colors and caption sentiment -- and structural factors like GDP, population, and obesity rates collectively shape consumer engagement. Using a multimodal analysis of Instagram posts from major food outlets across developed and developing countries, we assess how color schemes and sentiment influence key engagement metrics. We then extend this analysis with regression modeling to evaluate how these macroeconomic and demographic variables moderate engagement. Our results reveal that engagement patterns vary widely across regions. In developing countries, color combinations like off-white and green significantly enhance interactions, and GDP is a strong positive predictor of engagement. Conversely, in developed countries, a larger population boosts engagement while higher GDP correlates with reduced user attention. Obesity rates show a mixed influence, moderately enhancing likes in some regions while lowering comments in others. These findings highlight the critical need for localized digital marketing strategies that align content design with structural realities to optimize audience engagement.