Do Nutritional Status and Dietary Intake Influence the Ghrelin Response?

Background/Objectives: Ghrelin is a key orexigenic hormone involved in the regulation of appetite and energy homeostasis, and its fasting circulating concentrations may reflect long-term energy balance and nutritional status. The aim of the study was to assess the associations between habitual daily energy and macronutrient intake from a conventional diet and the fasting total ghrelin concentrations in individuals with different nutritional status and to evaluate the postprandial ghrelin response following consumption of a standardized meal. An additional aim was to identify body composition parameters predictive of ghrelin concentrations. Methods: The prospective study included 76 individuals aged 40–60 years, classified into four body mass index (BMI) groups. Body composition was assessed using dual-energy X-ray absorptiometry (DXA). Energy and macronutrient intake was evaluated based on standardized 3-day food records. Ghrelin concentrations were measured in the fasting state and at 60, 120, 180, and 240 min after consumption of a standardized mix liquid meal (Nutridrink Protein, 459 kcal). Results: Fasting total ghrelin concentrations were not associated with recent energy or macronutrient intake. In women, changes from the baseline differed across BMI groups at 60 and 120 min, whereas no between-group differences were observed in men. In the regression analyses, BMI and gynoid region fat showed significant coefficients in women, although the overall model was not significant, while gynoid region fat was significantly associated with fasting ghrelin in men. Conclusions: Fasting total ghrelin appears to reflect longer-term metabolic phenotype and adipose tissue distribution rather than short-term variation in habitual energy or macronutrient intake. The BMI-dependent differences in the early postprandial response observed in women further suggest that nutritional status may modify dynamic ghrelin regulation in a sex-specific manner. These findings indicate that ghrelin should not be interpreted solely as an acute marker of dietary intake, but rather within the broader context of body composition, fat distribution, and sex-related metabolic regulation.