When athletes are struggling with REDs, it’s common for them to come to their provider saying, “But I’m just not hungry.” For many athletes, this feels like proof that they’re eating enough. They assume that if their body needed more food, it would tell them. However, that’s not always the case. In fact, one of the most confusing and concerning aspects of chronic underfueling is that hunger cues often become less reliable over time. Athletes assume that appetite is an accurate reflection of energy needs, but in reality, hunger is regulated by a complex network of hormones, stress signals, exercise adaptations, and survival mechanisms. So when the body experiences prolonged low energy availability, those systems can change dramatically and lead to appetite suppression in athletes. Ironically, many athletes lose their hunger cues exactly when they need nourishment the most.
Hunger Is More Complicated Than Most People Think
Most of us grow up believing hunger works like a fuel gauge.
The tank gets low.
You feel hungry.
You eat.
Problem solved.
Not exactly… the human body is way more sophisticated than that.
Hunger is regulated by a complex interaction between:
- Hormones
- The brain
- Stress levels
- Energy availability
- Exercise
- Sleep
- Psychological factors
When these systems are functioning optimally, hunger and fullness cues help guide energy intake.
When energy availability remains low for an extended period, however, the body begins adapting in ways that can disrupt those signals.
Meet Leptin: Your Body’s Energy Status Messenger
One of the most important hormones involved in appetite regulation is leptin.
Leptin is produced primarily by fat tissue and acts as a messenger between the body’s energy stores and the brain.
Think of leptin as your body’s energy report card. When energy stores are adequate, leptin signals the brain that resources are available. When energy availability drops, leptin levels decrease.
Under normal circumstances, lower leptin should increase hunger and encourage eating. This is one of the body’s natural protective mechanisms against starvation. But things become more complicated when low energy availability persists.
What Happens During Chronic Underfueling?
In the early stages of underfueling, athletes often experience increased hunger.
However, when low energy availability becomes chronic, the body begins making broader adaptations to conserve energy.
This is where many athletes become confused. Instead of feeling ravenously hungry all the time, they may notice the opposite. Their appetite decreases, they stop thinking about food, and meals feel like a chore.
Eating becomes something they have to remember rather than something their body actively requests.
This phenomenon is thought to be part of a larger neuroendocrine adaptation designed to help the body survive periods of prolonged energy shortage.
In other words, the body begins prioritizing survival over performance.
Why Ghrelin Isn’t Always Enough
Another hormone involved in appetite regulation is ghrelin.
Often called the “hunger hormone,” ghrelin is produced primarily in the stomach and helps stimulate appetite.
Normally, ghrelin rises before meals and falls after eating.
However, in athletes experiencing chronic low energy availability, appetite regulation becomes more complex than simply increasing ghrelin levels.
The brain receives competing signals from multiple systems:
- Stress hormones
- Exercise stress
- Sleep disruption
- Psychological factors
- Energy conservation mechanisms
The result is that hunger signals may become blunted, inconsistent, or difficult to recognize.
Exercise Can Cause Appetite Suppression in Athletes
Many athletes notice they are least hungry immediately after their hardest training sessions.
This isn’t unusual.
Exercise itself can temporarily suppress appetite.
Research has shown that high-intensity exercise can alter appetite-regulating hormones and temporarily reduce feelings of hunger.
For athletes with adequate energy availability, this effect is usually short-lived.
For athletes who are already underfueling, however, repeated training sessions combined with inadequate recovery nutrition can contribute to a cycle of unintentionally missing opportunities to eat.
Over time, this can make it increasingly difficult to meet energy needs.
The Role of Stress and Cortisol
Training isn’t the only stress athletes experience. There’s work demands, school pressures, family responsibilities, competition anxiety, travel, financial concerns, and more.
All of these stressors influence the body’s hormonal environment. When stress levels rise, cortisol levels often increase as well.
For some individuals, stress increases appetite. For others, it suppresses it completely.
Many athletes experiencing REDs report feeling too stressed, too busy, or too exhausted to eat.
What they often don’t realize is that these experiences are closely tied to the same physiological systems being affected by low energy availability.
Signs Your Hunger Cues May No Longer Be Reliable
One of the biggest red flags I see in athletes experiencing REDs is not excessive hunger. It’s the absence of hunger.
Some common signs include:
- Forgetting to eat
- Low appetite despite high training volume
- Food apathy
- Feeling full quickly
- Skipping meals unintentionally
- Rigid eating patterns
- Lack of interest in food
- Exhaustion without hunger
- Feeling “fine” going long periods without eating
Many athletes interpret these signs as evidence they don’t need more food.
In reality, they may be signs that the body’s normal hunger signals have become dysregulated.
Why This Matters for REDs
One of the reasons REDs is so often missed is because athletes, coaches, and even healthcare providers assume hunger is an accurate marker of energy needs.
But hunger is not always reliable.
An athlete can be:
- Chronically underfueling
- Experiencing hormonal disruption
- Struggling with poor recovery
- Seeing declining performance
…and still report very little hunger.
This is why assessing energy availability requires looking beyond appetite alone.
The question is not simply:
“Are you hungry?”
The better question is:
“Are you meeting the energy demands your body requires to support health, recovery, and performance?”
Rebuilding Trust in Hunger During Recovery
One of the most challenging parts of REDs recovery is helping athletes understand that eating should not be dependent solely on hunger cues.
When hunger signals have been suppressed for months (or even years), waiting to feel hungry before eating can actually delay recovery.
In many cases, athletes must initially fuel proactively rather than reactively.
As energy availability improves, many athletes notice:
- Hunger cues becoming stronger
- Better recovery
- Improved mood
- Better sleep
- Improved performance
- More stable energy levels
Over time, the body begins to trust that energy is consistently available again.
The Truth About Appetite Suppression in Athletes
Many athletes believe that a lack of hunger means they’re eating enough.
But in reality, appetite suppression can be one of the body’s most sophisticated adaptations to chronic underfueling.
Low energy availability changes the way the brain, hormones, and nervous system communicate about food. As a result, athletes may lose hunger cues precisely when they need nourishment most.
A lack of hunger is not always a sign of adequate fueling. Sometimes it’s a sign that the body has been trying to survive on too little for too long.
Learn a Better Way to Assess Athletes
If you’re ready to understand the full spectrum of REDs, including the hormonal, metabolic, and behavioral adaptations that often go overlooked, I invite you to join the REDs Informed Provider Certification Program®.
Inside the program, you’ll learn how to:
- Identify early signs of low energy availability
- Understand appetite and hormonal adaptations in REDs
- Assess athletes beyond body weight and BMI
- Recognize non-stereotypical REDs presentations
- Implement evidence-based REDs screening and intervention strategies
This research-based certification program is designed to help providers confidently assess, identify, and support athletes experiencing REDs.
Join the REDs Informed Provider Certification Program® and learn how to recognize the signs athletes themselves may not see.