Although younger individuals may devour anything they see, elderly folks frequently experience a diminished hunger. Understanding the reasons behind this can help maintain health regardless of one’s stage in life.

Susanne Klaus, a lead researcher at the German Institute of Human Nutrition, suggested that our bodies often indicate what and when we should be eating, and perhaps we ought to pay closer attention.

It makes sense, but our body’s demand for energy varies over the course of our lives.

As babies, we rely on our parents to feed us with spoons; during childhood, we secretly enjoy sweet treats; as teens, we tend to eat voraciously; finally, in adulthood, we find ourselves picking at modest portions of plain food. Our tastes evolve over time, and grasping these changes may aid in maintaining better health as we age.

The hormones responsible for appetite and their functioning mechanisms

Fundamentally, consuming food serves a practical purpose: We require the energy it provides to stay alive.

In our diet, carbohydrates get transformed into energy, whereas fats and amino acids aid in constructing essential proteins and other components necessary for bodily functions.

To keep these processes running smoothly, the body has specialized systems in place to guarantee a consistent energy supply.

These regulatory processes govern feelings of hunger and fullness," explained Klaus. "These primarily involve signals originating from the stomach and intestines, along with hormonal cues like leptin, produced by fatty tissues. Leptin communicates with the primary region in our brain known as the hypothalamus. Similar to how we breathe without conscious thought, this constitutes an autonomous bodily function.

These biochemical triggers that push us towards (or away from) searching for food are often referred to as hunger hormones. Besides leptin, ghrelin is probably the most recognized of these hormones.

Ghrelin, which is produced by the stomach and enters the bloodstream, signals our brain to initiate food intake. As we become satiated, the secretion of ghrelin decreases, leading to a feeling of fullness.

Other hormones also control sensations of satiety and hunger. They encompass insulin along with other pancreatic hormones like GLP-1 that suppress appetite; these are targeted by medications for diabetes. Ozempic , mimics.

The mechanics of digestion

When these hormones encourage you to put food in your mouth, the body employs digestion to essentially consume your meal.

The mechanical breakdown of food starts in your mouth, where you chew and soften the food into a more manageable consistency for swallowing. As this semi-liquid mass moves through your throat and gets pushed into your stomach via muscular contractions called peristalsis, the process keeps going.

During this process, chemical digestion also takes place. It starts in the mouth with salivary amylase breaking down carbohydrates found in food. Further digestive enzymes continue this work in the stomach until all necessary breakdowns are complete, allowing for the absorption of water and nutrients through the intestinal walls into the bloodstream.

How your hunger levels evolve as you get older

This urge for food intensifies as you enter adolescence. The body demands more energy to support its primary growth phase—puberty—which propels it towards achieving both physical and sexual maturation.

However, maintaining proper nutrition throughout one’s lifetime can pose challenges. Particularly for elderly individuals, their bodies may become less efficient at signaling the required nutrient consumption. Various studies have indicated alterations in the pattern of hunger hormones as people age.

"As individuals grow older, they typically experience a reduction in muscle mass, and this muscular tissue generally consumes the highest amount of energy," explained Klaus.

However, a key reason for the decrease in muscle mass is not eating enough protein.

According to Daniel Crabtree, a researcher focusing on nutrition in later stages of life from the University of Aberdeen, "The consumption of proteins during old age falls short of the suggested levels, and these guidelines might not even be high enough. Scientific organizations suggest increasing the recommended protein intake for older individuals since maintaining muscle mass becomes crucial as we get older."

Even though advised otherwise, Crabtree mentioned that elderly individuals often consume less protein than suggested, which might involve various physiological aspects and indications of aging bodies—ranging from dental issues to alterations in taste or smell sensitivity.

Edited by: Zulfikar Abbany

Author: Matthew Ward Agius