Cortisol: The Good, The Bad & The Truth About Your Body’s “Stress Hormone”

Cortisol has become one of the most misunderstood hormones in health and fitness.

Scroll through social media and you'll hear that cortisol is responsible for belly fat, weight gain, muscle loss, poor sleep, fatigue, cravings, and almost every other health problem imaginable.

So naturally, people start asking:

"How do I lower my cortisol?"

But here's what gets missed:

You don't want to eliminate cortisol.

You couldn't function normally without it.

Cortisol isn't the enemy.

The real issue is understanding what cortisol does, why your body produces it, and what can happen when the body's stress system is disrupted for prolonged periods.

Let's break it down.

What Is Cortisol?

Cortisol is a steroid hormone produced by your adrenal glands.

It's part of your body's hypothalamic-pituitary-adrenal axis, commonly called the HPA axis.

This system helps your body respond to physical and psychological stress.

But cortisol does much more than respond to stressful situations.

It helps regulate:

• Blood glucose
• Metabolism
• Blood pressure
• Inflammation
• Immune activity
• Energy availability
• Your sleep-wake cycle

In other words:

Cortisol is necessary.

The goal isn't low cortisol.

The goal is appropriate cortisol regulation.

Cortisol Is Supposed to Change Throughout the Day

Cortisol isn't meant to stay at one level.

Your body follows a natural daily rhythm.

Generally, cortisol rises around the time you wake up, helping your body transition into an alert and active state.

Levels then tend to gradually decline throughout the day and become lower at night.

That's normal.

You want cortisol available when you need energy and alertness.

And you want your body's stress-response systems to settle when it's time to recover and sleep.

The problem isn't:

"My cortisol went up."

Cortisol is supposed to go up.

• Exercise increases cortisol.
• Waking up increases cortisol.
• Psychological stress can increase cortisol.
• Low blood sugar can stimulate cortisol.
• Illness and injury can increase cortisol.

That's your body doing its job.

Acute Stress vs. Chronic Stress

This distinction matters.

Imagine you're about to perform a heavy set of squats.

Your nervous system becomes more alert.

Your heart rate increases.

Stress hormones rise.

Energy becomes available.

You perform.

Then you recover.

That's an acute stress response.

Your body is designed to handle temporary stress.

The bigger concern is when significant stress becomes chronic and recovery remains inadequate.

• Financial stress.
• Relationship stress.
• Work stress.
• Poor sleep.
• Constant dieting.
• Excessive training.
• Illness.
• Alcohol.
• Not eating enough.
• Never taking time to recover.

Your body doesn't categorize stress the way you do.

To your physiology, stress is stress.

Does Cortisol Cause Belly Fat?

This is where we need some nuance.

You've probably heard: "High cortisol makes you store belly fat."

That's an oversimplification.

Long-term cortisol excess — such as occurs in certain medical conditions — can contribute to changes in body-fat distribution and metabolism.

Chronic psychological stress can also influence eating behavior, appetite, sleep, activity, and metabolic health.

But if someone is gaining abdominal fat, we can't simply look at them and say: "Your cortisol is high."

Body-fat gain is influenced by energy balance, genetics, food intake, activity, sleep, hormones, medications, age, and numerous other factors.

So don't let someone diagnose your cortisol levels based on your stomach.

That's not how medicine works.

Cortisol and Muscle

Now this is especially important for anyone interested in strength and longevity.

Cortisol has catabolic effects, meaning it can help mobilize stored energy and influence protein metabolism.

Again, that's not automatically bad.

Your body constantly moves between building and breaking down tissue.

Exercise itself temporarily increases muscle protein breakdown and physiological stress.

Then you recover.

You eat protein.

You sleep.

Muscle protein synthesis increases.

Your body adapts.

That's training.

The concern is when the equation becomes consistently unbalanced:

High stress + inadequate nutrition + poor sleep + excessive training + inadequate recovery.

Under those conditions, maintaining or building muscle becomes more difficult.

That's why recovery isn't separate from training.

Recovery is part of training.

Cortisol and Blood Sugar

One of cortisol's important jobs is ensuring your body has enough available energy during stress.

Cortisol can help increase glucose availability.

Imagine you're running from danger. Your body doesn't want to say: "Sorry, we're saving this glucose for later."

It makes fuel available.

That's useful.

But chronic disturbances in stress hormones combined with poor sleep, inactivity, excess calorie intake, and other metabolic problems can contribute to an environment associated with impaired glucose regulation.

Again, cortisol isn't evil.

Context matters.

Cortisol and Sleep Can Become a Vicious Cycle

Sleep and stress are closely connected.

Stress can interfere with sleep.

Poor sleep can alter the body's stress response.

Then you're exhausted the next day.

You drink more caffeine.

You're less active.

Your appetite may change.

Your workout suffers.

You become more stressed.

Then you sleep poorly again.

And the cycle continues.

This is why someone trying to improve their health can't focus exclusively on workouts and nutrition.

Sleep matters.

A lot.

Exercise Raises Cortisol — And That's Okay

This surprises people.

A hard workout is a stressor.

Your body responds accordingly.

Cortisol may rise temporarily during exercise, particularly with longer or more intense training.

That doesn't mean exercise is damaging your hormones.

The stress created by exercise is one of the signals that encourages your body to adapt.

Think about strength training.

You challenge your muscles.

Your body repairs them.

You become stronger.

Exercise is essentially:

Stress → Recovery → Adaptation

The problem comes when we repeatedly create stress without providing enough recovery.

More Exercise Isn't Always Better

This is particularly important for people who believe they need to punish themselves into better health.

They're eating very little.

Doing intense cardio.

Strength training.

Sleeping five hours.

Working stressful jobs.

Drinking multiple energy drinks.

And then wondering why they feel exhausted.

Sometimes the answer isn't:

"Train harder."

Sometimes the answer is:

Recover better.

Your body needs enough calories.

Enough protein.

Enough sleep.

Rest days.

And periods where training intensity decreases.

Fitness isn't about seeing how much punishment your body can tolerate.

It's about giving your body a stimulus it can adapt to.

How Do You “Lower Cortisol”?

I don't love that phrase.

The goal should be improving your ability to manage stress and recover, not trying to keep cortisol permanently low.

For most people, that means getting the fundamentals right:

• Get adequate sleep.
• Strength train regularly without turning every workout into a war.
• Include lower-intensity movement like walking.
• Eat enough protein and overall nutrition.
• Avoid extreme dieting.
• Manage caffeine appropriately, particularly later in the day.
• Limit excessive alcohol.
• Spend time outside.
• Maintain meaningful relationships.
• Give yourself actual periods of recovery.

And if persistent symptoms suggest a medical or hormonal problem, talk with a qualified healthcare professional instead of relying on a "cortisol detox."

Be Careful With “Cortisol Supplements”

There's an entire industry built around convincing people their hormones are broken.

You may see products advertised as:

• Cortisol blockers.
• Adrenal support.
• Hormone resets.
• Cortisol detoxes.

Be skeptical.

Feeling stressed doesn't automatically mean you have clinically abnormal cortisol levels.

And feeling tired doesn't automatically mean you have "adrenal fatigue."

If you believe something is medically wrong, get appropriately evaluated.

Don't let an Instagram advertisement diagnose your endocrine system.

Stress Isn't Something You Can Completely Eliminate

Here's another mistake.

People believe optimal health means eliminating stress.

That's impossible.

And it isn't desirable.

Exercise is stress.

Learning is stress.

Competition is stress.

Building a business is stress.

Raising children can be stressful.

Challenging yourself creates stress.

The human body is built to experience stress.

The goal is developing enough capacity and recovery to handle it.

That's a completely different mindset.

Build a Body That Can Handle Stress

This connects directly to why I emphasize strength, muscle, cardiovascular fitness, nutrition, and sleep.

You aren't trying to create a life where nothing difficult ever happens.

You're building a body capable of responding when difficulty arrives.

That's resilience.

Train.

Recover.

Adapt.

Repeat.

Over time, you're increasing what your body can handle.

The UOU Perspective

At UOU, we're not afraid of stress.

We respect the relationship between stress and recovery.

You need stress to grow.

Your muscles need resistance.

Your cardiovascular system needs challenges.

Your bones need loading.

Your mind needs challenges.

But adaptation happens when you give your body the resources to recover from those challenges.

So stop thinking:

"Cortisol is bad."

Instead, understand what your body is telling you.

Stress isn't automatically the problem.

Stress without adequate recovery is where problems can begin.

Train hard enough to create adaptation. Eat enough to support it. Sleep enough to recover from it.

And build a body that's increasingly capable of handling what life throws at you.

Stress. Recover. Adapt.

You Owe You.

— Coach Dante