What an Overreactive Nervous System Is and How to Calm It

Your nervous system responds automatically to threats—real or imaginary—shaping your emotional state and behaviors.

MattL_Images/Shutterstock

Heidi, a 34-year-old former ballet dancer, found herself trapped in a cycle of digestive pain, anxiety, and bouts of extreme exhaustion. Despite feeling that her body was desperately signaling for help, Heidi was unaware that the root cause lay in her overreactive nervous system.

Like a malfunctioning home security alarm that couldn’t be silenced, Heidi’s internal defenses were in a constant state of high alert. Her perfectionist tendencies were a manifestation of her sympathetic nervous system’s response—a self-protective strategy to ward off her fear of failure.

This perpetual “fight-or-flight” state was taking its toll, pushing her to the brink of collapse as she struggled to avoid the very pain and exhaustion she feared.

Heidi’s story illustrates an overlooked fact: Our emotions aren’t merely fleeting feelings but signals from a nervous system responding to perceived threats, both real and imagined.

For those living with chronic stress or unresolved trauma, the nervous system can become stuck in this state of hypervigilance, a condition clinically known as a dysregulated nervous system.

The Body’s Alarm System

Our nervous system is designed to assess threats and ensure safety. The autonomic nervous system, regulating the body’s involuntary functions, is its command center. A balanced nervous system allows us to navigate social interactions with ease.

In 1994, Stephen Porges, a renowned professor of psychiatry, introduced the Polyvagal Theory, expanding modern understanding of the nervous system. This theory posits three states: safe connection, fight-or-flight, and freeze.

The vagus nerve, a key component, links the body’s organs to the brain and plays a vital role in both the nervous system and gut health. Porges connected social behavior with these nervous system states, coining the term “social engagement system.” This framework explains why some people struggle to shift out of survival modes.

The 3 States of the Nervous System

Until the mid-1990s, physiologists recognized only two states of the autonomic nervous system: sympathetic “fight or flight” and parasympathetic “rest and digest.” Porges discovered that the vagus nerve has two parts—dorsal and ventral—revealing three distinct nervous system states.

1. Green: Ventral Vagal (Relaxed)

• Calm energy, secure and confident responses
• Usually trust others with ease and open to social connection
• Promotes growth, repair, and energy restoration

2. Yellow: Sympathetic (Fight or Flight)

• High energy, adrenaline-fueled response
• May feel defensive and unsupported
• With proper support, can return to the green state

3. Red: Dorsal Vagal (Freeze/Shutdown)

• Overwhelm response, primitive survival mode
• Low energy and motivation
• Difficulty asking for help or trusting others

It’s normal to move fluidly between these states throughout the day. For instance, you might be in green while talking with a loved one but shift to red if rebuked at work. The key is not to get stuck in yellow or red states.

Getting Stuck in Stress

Two main reasons we get stuck in yellow or red states are overwhelming stress, when the stress load becomes too much to handle, and prolonged lack of support, which is insufficient support over extended periods.

These factors can create a negative feedback loop between emotions, thoughts, and brain chemistry. For instance, anxious or negative thoughts trigger cortisol release, leading to more anxiety and further cortisol production.

Common signs of nervous system dysregulation include:

• Poor sleep (difficulty falling asleep or frequent waking)
• Obsessive thought patterns (e.g., food rituals or avoidance)
• Increased irritability and sensitivity to criticism
• Constant feeling of being overwhelmed
• Chronic physical and emotional issues (muscle aches, abdominal pain, frequent illness, low energy, mood swings)

In contrast, a regulated nervous system is characterized by calmness, steady breathing, relaxed muscles, even emotions, and mental clarity.

While momentary dysregulation is normal, a person can train his or her nervous system to reset more quickly through awareness, biological support (nutrition and herbal), and practice. The goal is to gradually increase time spent in a state of clarity and calm.

Ways to Soothe Your Nervous System

A disrupted neurochemical balance in the brain negatively affects thoughts and emotional responses, affecting everything from health to relationships. Therefore, mastering the nervous system is key to maintaining good overall well-being.

Ways to calm an overly sensitive nervous system include the following:

• Eat three regular, small meals daily with protein, healthy fat, and fiber from half a plate of vegetables at each meal. Unbalanced or skipped meals can lead to extremes in blood sugar levels and trigger the release of stress hormones.
• Practice deep breathing or meditation, which can change brain waves and lower stress hormones.
• Take daily walks (20 to 30 minutes) to lower cortisol levels.
• Journal: Writing out your feelings can help you express your experience rather than ruminate on it.
• Seek support by talking with someone you trust; it’s an act of courage to ask for help.
• Consider biochemical support, such as a therapeutic dose of high-quality magnesium powder.

Heidi began to recognize the connection between her body and mind’s lack of nourishment and the extreme stress swings she'd experienced, ranging from hyperactivity to complete shutdown. To validate this observation with real-time data, she wore a continuous glucose monitor for 14 days to track her blood sugar levels. This data indeed revealed that frequently skipping meals sent her blood sugar levels far too low (medically termed hypoglycemia) and worsened her anxiety and stress hormones.

She then implemented various nutritional and lifestyle changes, including eating regularly, getting enough sleep, and exercising, to calm her nervous system and reduce her emotional triggers.

As a result, Heidi’s mindset became more positive. She internalized the fact that she was indeed safe and not constantly in danger.

This holistic approach helped Heidi stabilize her blood sugar levels and better regulate her nervous system, improving her emotional balance and reducing stress swings.