True hunger is a rare experience for most people in the developed world. What people typically experience are feelings of desire for particular foods or a need to feel ‘full’. And the key to feeling full could be as simple as a bowl of soup.
Satiety is the term scientists use to mean the feelings of fullness we experience after a large meal. What drives satiety is a complex mix of psychological and physiological factors including physical stretching of the stomach and small intestine from food and a cascade of release of hormones that feed back into the brain to tell us we are full.
One well-researched way to help control how much food a person eats is to choose foods that have a low energy density. Foods high in water content, rich in fibre, and low in fat help to decrease the energy density of a meal, providing more satiety for fewer kilojoules. Eating lots of foods with a low energy density means a person can eat a larger volume of food, with less kilojoules consumed.
Taking the concept of energy density one step further, there has been interest in the way that soup may help control satiety. Liquids are considered to not be as satiating as solid foods, but when it comes to soup opinion is divided.
While soup is mostly liquid, it can contain an appreciable amount of food nutrients as well. One theory is that the food particles in soup help slow the release of the soup from the stomach, giving a more sustained feeling of fullness, reducing the chance of overeating.
The soup test
Just published in the European Journal of Clinical Nutrition, scientists put the satiating soup theory to the test. Twelve healthy volunteers consumed three different meals on three separate occasions. The meals were a solid meal, a chunky soup and a smooth soup. Measurements were made after each meal of the rate the food left the stomach, changes in blood sugar levels, and subjective feelings of satiety.
The smooth soup was the clear winner by giving the highest rating for satiety, while at the same time had the slowest rate of stomach release.
Interestingly, the smooth soup also had the highest effect on blood glucose levels, which is thought to be because of the small particle nature of food contained in soup making it easier to absorb. A quicker release of carbohydrate into the blood stream means the faster release of nutrient sensing hormones that help turn off appetite.
What it all means
A healthy and hearty soup can be just the thing to help kill a ravenous appetite.