When we think of ghrelin, we usually think of hunger, that unmistakable signal that tells us it is time to eat. Ghrelin has earned its reputation as the body’s primary “hunger hormone”

But what many people don’t realise is that ghrelin has a lesser-known counterpart, a kind of hormonal twin that does not increase appetite at all. 

…Instead, it quietly works behind the scenes, influencing how our bodies manage energy, fat storage, and metabolism…

This hormone is called des-acyl ghrelin, and emerging research suggests it may play a powerful role in metabolic health, obesity, and insulin regulation.

What is Des-Acyl Ghrelin?

Des-acyl ghrelin is a non-acylated form of ghrelin, meaning that it lacks the fatty acid modification (acylation) that allows ghrelin to bind to hunger-stimulating receptors in the brain.

Both ghrelin and des-acyl ghrelin are produced mainly in the stomach and released into the bloodstream in similar amounts. 

…However, because des-acyl ghrelin cannot activate the ghrelin receptor, it does not stimulate appetite…

For many years, this led scientists to believe des-acyl ghrelin was biologically inactive. We now know that the assumption was wrong.

Despite not increasing hunger, des-acyl ghrelin plays a meaningful role in:

• Energy regulation, 
• Glucose metabolism, 
• Fat utilisation, and 
• Cardiovascular function. 

This has sparked growing interest in its potential therapeutic value.

Ghrelin vs. Des-Acyl Ghrelin: A Powerful Contrast

Although they originate from the same hormone precursor, ghrelin and des-acyl ghrelin exert very different effects on the body.

Ghrelin (Acylated Ghrelin)

• Stimulates hunger and food intake
• Promotes fat storage
• Influences glucose metabolism
• Elevated levels are often linked to obesity and metabolic disorders

Des-Acyl Ghrelin

• Does not stimulate appetite
• Influences insulin sensitivity
• Supports fat metabolism and energy expenditure
• May counterbalance some of ghrelin’s effects

Rather than driving hunger, des-acyl ghrelin appears to support metabolic efficiency, helping the body use energy more effectively instead of storing it

The Role of Des-acyl Ghrelin in Energy Homeostasis

Des-acyl ghrelin’s involvement in energy homeostasis is still a subject of ongoing research, but several important roles have already been identified:

1. Regulation of Insulin Sensitivity

One of the most promising findings is des-acyl ghrelin’s ability to improve insulin sensitivity.

Research suggests that, unlike ghrelin, which may worsen insulin resistance, des-acyl ghrelin can support glucose regulation. This makes it particularly relevant in conditions such as:

• Insulin resistance
• Type 2 diabetes
• Metabolic syndrome

Improved insulin sensitivity allows cells to use glucose more effectively, reducing excess blood sugar and limiting fat storage.

2. Fat Mobilisation and Energy Expenditure

Des-acyl ghrelin has been linked to increased lipolysis, the breakdown of stored fat for energy.

By encouraging the body to access fat stores rather than preserve them, des-acyl ghrelin may help:

• Limit fat accumulation
• Support weight regulation
• Improve metabolic flexibility

This contrasts sharply with ghrelin’s tendency to promote fat storage, highlighting their opposing roles in metabolism.

3. Indirect Effects on Appetite Regulation

Although des-acyl ghrelin does not directly trigger hunger, it may influence appetite indirectly.

Animal studies suggest that higher levels of des-acyl ghrelin can reduce food intake, even when ghrelin levels are elevated. 

This implies that des-acyl ghrelin may help dampen ghrelin’s appetite-stimulating effects, contributing to a more balanced regulation of hunger and satiety.

4. Cardiovascular Health

Emerging evidence also suggests a role for des-acyl ghrelin in cardiovascular protection.

Potential benefits include:

• Improved vascular function
• Reduced inflammation
• Protective effects on heart tissue

Given the close link between metabolic disease and cardiovascular risk, these findings add to the hormone’s therapeutic appeal.

Des-Acyl Ghrelin and Obesity

The relationship between des-acyl and obesity is complex but compelling. 

While ghrelin promotes fat storage and increased energy, des-acyl ghrelin may help counteract some of these effects by:

• Enhancing insulin sensitivity
• Increasing energy expenditure
• Supporting fat utilisation

Together, these actions suggest that des-acyl ghrelin could play a protective role against obesity and its related metabolic complications.

However, the balance between ghrelin and des-acyl ghrelin appears to be critical. 

Researchers are still working to understand how shifts in this balance influence weight regulation and metabolic health.

The Future of Des-Acyl Ghrelin in Therapeutics

As research advances, des-acyl ghrelin is gaining attention as a potential therapeutic target for:

• Obesity management
• Improving insulin sensitivity
• Reducing metabolic disease risk
• Supporting cardiovascular health

One of the main challenges lies in developing treatments that enhance or mimic des-acyl ghrelin’s effects without disrupting the natural balance between the two forms of ghrelin.

If this balance can be achieved, des-acyl ghrelin may offer a novel and powerful approach to metabolic health.

Summary

Des-acyl ghrelin may not stimulate hunger, but its influence on metabolism, insulin sensitivity, and fat utilisation makes it a crucial, and often overlooked, player in energy homeostasis.

While ghrelin pushes the body toward eating and fat storage, des-acyl ghrelin appears to work in the opposite direction, helping the body use energy more efficiently and maintain metabolic balance.

As science continues to uncover its mechanisms, this “dark twin” of ghrelin may become a key ally in the fight against obesity and metabolic diseases.


Lydia, is a Specialist Dietitian at The London Obesity & Endocrine Clinic. She has helped many patients overcome weight management barriers. ©Simplyweight

Top obesity clinic in Chennai