Introduction to the Nervous System: 

In the hustle and bustle of modern life, our nervous system plays a crucial role in regulating our responses to the constant flow of stressors. Its function is to help us differentiate between a situation where we may be in danger vs. one that is likely harmless. In order to do this, the central nervous system (autonomic specifically) is composed of two parts: the sympathetic and parasympathetic nervous systems. Together, these two parts work in tandem in an effort to maintain equilibrium in our bodies while keeping us safe. However, sometimes, they lose balance from one another, shifting too far in one direction, and have trouble regaining equilibrium.

In this post, we explain what the nervous system is responsible for, how it impacts your health, and actionable diet and lifestyle modifications to support your nervous system and health. 

Sympathetic vs. Parasympathetic Nervous System – What’s the Difference? 

Your nervous system acts as your body’s command center. It is constantly listening to the body and receiving messages thanks to our complex system of neurons and cells that repeatedly scan our environment and gather information from our five senses (sight, sound, smell, taste, touch). The inputs our nervous system receives from the body and environment dictate which part of the nervous system is active at that moment. 

Your Sympathetic State: 

Picture this: your heart races, your breath quickens, and a rush of anxiety comes over you—your body is on high alert. Welcome to the sympathetic state, often dubbed the “fight or flight” response. When facing stress and danger, or in this day in age,  sleeping in past your alarm, running late to a meeting, or looming deadlines, this state readies you for action. Cortisol courses through your veins, heightening your senses and boosting your energy levels. 

While the Sympathetic State is a protective mechanism and undoubtedly helpful at times, it’s meant to be short-lived, having to enter this state temporarily and then returning to the parasympathetic state. 

The Parasympathetic State: 

Now, picture a calm oasis: your heart rate steadies, your breath deepens, and a sense of calm comes over you. This is the parasympathetic state, known as the “rest and digest” response. This state takes the reins when you’re in a peaceful setting and free from stressors. Cortisol levels drop, and your body focuses on digestion, relaxation, and repair. In an ideal world, your body should be in a parasympathetic state the majority of the time, only entering a sympathetic state when there is a true threat. 

When the sympathetic nervous system takes over

Unfortunately, many of us are living in a constant sympathetic state – meaning our bodies are in a chronic condition of “fight or flight” where our body is responding inappropriately to environments that shouldn’t trigger such a response and is unable to shift back into a place of balance and calm. 

As a result, being in a sympathetic state for a prolonged period can take a toll on our health and well-being and may result in the following: 

• Feelings of Chronic Stress and Anxiety – Thanks to increased stress hormones like norepinephrine and epinephrine that work to elevate your breathing and heart-rate, and cortisol, which can make you feel irritable and anxious. 
• Trouble Sleeping – Heightened stress hormones negatively impact falling and staying asleep. Think about it like this – if your body is on high alert, it doesn’t want you to be sleepy. 
• Hormonal Imbalances – With increased stress comes increased cortisol which may affect the balance of other hormones like estrogen and progesterone.
• Poor Gut Health – Blood flow is diverted from the GI tract and prioritized to essential organs like the heart, so digestion slows during this time. Additionally, stress and inflammation go hand in hand, where the gut may experience increased inflammation, negatively affecting the gut lining and microbiome. 
• Weight Changes – One impact of excess cortisol is increased weight gain, particularly around the abdomen. 
• Exhaustion and Burnout – While you will get an immediate rush of energy, over time, the body (think adrenal glands and hormones) will become so fatigued from working overtime that you actually become flat-out exhausted. 

If you’re experiencing these symptoms, don’t panic! Know that you’re not alone in this and that your body doesn’t have to feel like this forever. Keep reading to find out how you can shift from a place of “fight or flight” to “rest and digest.”

Health Benefits of the Parasympathetic Nervous System

On the flip side, your parasympathetic comes with a host of positive health benefits for your body, given it promotes digestion, relaxation, and repair resulting in: 

• Quality Sleep 
• Improved Digestion 
• Hormone Balance 
• Boosted Immunity
• Decreased Inflammation 
• Improved mood and cognition 

How to Shift Your Body from Sympathetic to Parasympathetic 

Here’s the good and bad news. The good news is that you have the power to shift your body from a sympathetic to a parasympathetic state. Here’s the less good news, depending on how long you’ve been living in the sympathetic impacts and how long it’s going to take to shift you out of it. Sometimes an action as simple as taking three deep belly breaths will do the trick, but other times it takes a complete diet and lifestyle revamp to truly “reset” your nervous systems and hormones to enter the parasympathetic. 

In any case, below are some simple yet effective tools and methods to assist your body in this process 

• Breathwork and Meditation – Boosts mood by increasing dopamine, decreases stress by its impact on cortisol and DHEA (a hormone involved in the stress response by reducing inflammation), and may, therefore, positively impact hormone and gut health
• Slowing down – This isn’t the time to keep adding things to your calendar. Instead, be thoughtful and take a look at what events/activities aren’t serving you. 
• Low-Impact Exercise – Prioritize movement like walking, pilates, and yoga over HIIT, which induce excess stress on the body 
• Getting outside – Being outside in nature has been shown to decrease stress, boost mood, and even lower blood pressure, and improve our sleep 
• Focusing on Sleep Hygiene – Sleep is the foundation of your overall health, directly impacting your hormones, energy, mood, and even gut health. Engaging in behaviors promoting a restful night’s sleep will help decrease stress levels. 
• Nourishing your body  – Making sure to eat enough here is key. This isn’t the time to skip meals or cut out food groups as it is an added stressor to your body; instead, you want to focus on balanced meals (protein, fat, and carbohydrates) and snacks throughout the day.
• Digital Detox – Our electronics are a constant influx of stimulus that our body has to interpret and decipher. Our digital devices can often become too much when our body is on overdrive. Consider taking some time off social media or setting limits on screen time. 
• Setting boundaries in your work, personal life, and with yourself – This one can go a long way! Sitting down and evaluating what/who is bringing you joy and what/who is draining you and then setting boundaries to ensure more joy and less negativity can do wonders for your mental and physical health.  
• Making time for meaningful connections – This can be so important to our healing journey. Spending time with friends and family has been shown to improve mental health, boost self-confidence, improve resilience (or stress response), and enhance overall health. 
• Humming and Singing – Not only is this fun but it activates the Vagus Nerve, which is an essential component of your parasympathetic nervous system and “rest and digest.” 

For more, be sure to check out our post titled “Lifestyle Practices to Benefit the Whole Body” 

Note that while these practices will help to engage the parasympathetic nervous system, if you’re experiencing a handful of the symptoms I listed above, including hormonal imbalances (looks like feeling hyper-emotional, exhausted, weight gain, etc.)., digestive distress (chronic bloating, constipation/diarrhea, etc.), and more than these practices are only going to get you so far. 

In these cases, your body likely needs some serious support from an experienced health practitioner who understands how to address the root cause to heal hormonal and gut imbalances to shift you into a parasympathetic state successfully. 

Conclusion

In pursuing optimal health, nurturing a balanced nervous system is critical. By recognizing the signs of sympathetic and parasympathetic states, understanding the reasons behind imbalances, and implementing practical strategies to promote relaxation, you can harness the power of your nervous system to transform your overall well-being.

Ready to leave a life of fight or flight and enter a state of rest and digest? Reach out! 

Written by Alison Richman MS, RDN