Why do some people feel hungry shortly after eating, while others remain satisfied for hours? The answer may involve more than the size of a meal or the nutrients it contains.

Scientists have discovered that body composition, particularly where adipose tissue is stored, may be associated with the activity of ghrelin, a hormone that helps regulate appetite.

Their findings suggest that longer-term metabolic characteristics could explain certain differences in hunger signals more effectively than recent dietary intake. The study, published in Nutrients in October 2026, offers new insights into the complex relationship between body weight, hormones and appetite regulation.

What Is The Hunger Hormone?

Ghrelin is a hormone produced primarily in the stomach. Its concentration typically rises before meals, helping signal hunger to the brain, and decreases after eating.

This process contributes to the body's regulation of food intake and energy balance. However, ghrelin levels vary between individuals. Researchers have been investigating whether these differences are associated with eating habits, body weight or the distribution of adipose tissue.

Understanding these relationships could improve scientific knowledge of appetite regulation and metabolic health.

How Researchers Studied Appetite

The investigation involved 76 adults aged between 40 and 60, divided equally into four categories based on body mass index (BMI). Participants included people with a weight within the conventional BMI range, those classified as overweight and individuals with different degrees of obesity.

Researchers assessed body composition using specialised scans and collected three-day food records to estimate energy and nutrient intake.

Participants then consumed a standardised liquid meal containing approximately 459 calories. Blood samples were collected before eating and at hourly intervals over the following four hours to measure changes in ghrelin concentrations. This allowed scientists to examine how the hormone behaved in relation to body composition and recent eating patterns.

Does Daily Diet Affect Hunger?

One of the most interesting findings concerned the relationship between food intake and fasting ghrelin levels. Across the study population, researchers found no significant association between fasting ghrelin concentrations and the reported intake of calories, protein, carbohydrates or dietary lipids.

An association involving carbohydrate intake appeared among overweight participants, but the evidence was insufficient to establish a consistent pattern across weight categories.

These results suggest that short-term dietary records may provide limited information about an individual's fasting hunger hormone levels. However, they do not mean that food choices have no effect on appetite or that dietary composition is unimportant.

Why Body Composition Distribution Matters

Researchers also examined whether the location of stored adipose tissue was associated with hormonal differences. Among men, a lower proportion of adipose tissue around the hips and thighs was significantly associated with higher fasting ghrelin levels. In women, BMI and adipose distribution showed individual associations with ghrelin, although the combined statistical model did not reach significance. These findings raise the possibility that body composition influences hunger-related hormonal patterns in ways that BMI alone cannot fully explain. However, the observed associations do not establish that adipose distribution directly causes changes in appetite.

What Happens After Eating?

Ghrelin concentrations generally declined during the first hour after the test meal, then gradually moved towards their original levels over the following three to four hours.

Women classified as overweight or having class I obesity showed particularly pronounced early decreases. Nevertheless, the overall analysis did not establish a statistically significant difference in hormone responses across BMI groups over time. The researchers also found no confirmed BMI-related differences in post-meal responses among men.

What Does This Mean For Health?

The findings highlight the complexity of appetite regulation and suggest that ghrelin should be interpreted alongside broader metabolic characteristics.

The study was relatively small, relied on short dietary records and examined responses to only one type of meal. Larger investigations are needed to confirm the results.

For now, the research offers a useful reminder that hunger is influenced by multiple biological processes. Understanding those processes could eventually support more personalised approaches to nutrition and metabolic health.