What Really Happens to Your Body During Surgery?
Understand the changes, ease your worries, and take steps to support your recovery
Surgery is a big moment for your body. It’s not just what happens during the operation itself, but everything your body does to cope and heal afterward. Understanding these changes can help you feel more confident as you prepare, and it may even make your recovery smoother.
Here we’ll break down what happens during surgery, common changes you might notice afterward, and simple steps you can take to support your healing journey.
High-yield takeaways:
Surgery places stress on your body. Knowing what to expect helps you prepare and recover.
The body’s stress response triggers inflammation, hormone shifts, and fluid changes.
Pain, anesthesia, and medications can affect digestion, mood, energy, and immune function.
Small steps like eating well, moving your body, and supporting your mindset can make a real difference.
How surgery stresses the body (in ways that help and challenge you)
When you have surgery, your body kicks into “repair mode.” This starts with a stress response designed to protect you and start the healing process.
Here’s what happens behind the scenes:
Inflammation ramps up to help defend against infection and begin repairing tissue.
Hormone changes occur. Stress hormones like cortisol and adrenaline rise, helping your body deal with the trauma of surgery.
Fluid shifts take place as part of this natural response, which can lead to temporary swelling or changes in how your body balances water and salt.
This stress response is normal and important, but it takes energy. If your body is already run down, or if the stress is prolonged, healing can be slower.
Surgery also affects the immune system. In the first few days after an operation, the body’s ability to fight infection is lower. This is one reason good preparation and care afterward are so important.
Depending on the type of surgery, certain organs may need extra support:
The lungs may not expand as fully, especially if pain makes deep breathing uncomfortable. This can raise the risk of pneumonia if you don’t do breathing exercises.
The gut tends to slow down, leading to constipation or bloating.
The heart works harder during and after major surgeries, which is another reason recovery needs to be gradual.
Common changes you may notice after surgery
Everyone’s experience is a little different, but here are some of the most common changes:
Fatigue. Your body is using energy to heal, so you may feel more tired than usual.
Appetite loss or nausea. This can happen from the stress of surgery or from medications.
Muscle breakdown. When you’re less active, even for a short time, muscle mass can start to decrease.
Constipation. Slowed digestion is common, especially if you’re taking pain medications.
Mood changes. It’s normal to feel a little down, anxious, or emotional after surgery.
Pain and certain medications, especially opioids, can add to these effects by making you feel groggy, affecting your mood, and slowing digestion.
What influences how you recover?
Your recovery will depend on a mix of factors, including:
Your age and overall health. The healthier you are going into surgery, the better your body can handle the stress.
The type of surgery. Some procedures are more demanding on the body than others.
Your mindset and stress level. Worry and stress can actually amplify the body’s stress response, which may make healing slower or harder.
That’s why preparing in both body and mind is so valuable.
What you can do now to support your body
The good news is that even small steps before surgery can set you up for a smoother recovery. Here’s what we recommend:
Prioritize good nutrition. Focus on getting enough protein, vitamins, micronutrients and fluids in the weeks before surgery. Your body needs these building blocks to heal well.
Keep moving as you’re able. Short walks, gentle stretching, or simple breathing exercises can help maintain strength, support your lungs, and improve circulation.
Support your mindset. Practices like deep breathing, relaxation techniques, or simply imagining a successful recovery can help lower stress and promote healing.
Stay informed. Knowing what to expect can help ease worry and give you a sense of control.
Looking ahead
Surgery is hard work for you and your body. But when you take time to prepare, you give yourself the best chance at a smooth recovery. Small daily steps really do add up.
If you’d like more support as you get ready, explore our other resources:
Download our Pre-surgery checklist
Also, please remember before making any changes to your nutrition, exercise, or recovery plan, be sure to check in with your surgeon, physician, or healthcare team. They can help guide you based on your individual needs and medical history.
Prepare well, heal well. Our team is here to help you every step of the way.