How Do You Fix Grief Insomnia and Fatigue According to The Grieving Body (2025)?

Why Does Grief Cause Physical Pain? A Neuroscientist’s Guide to Healing Your Body After Loss

Discover why grief affects sleep, immunity, and digestion in Mary-Frances O’Connor’s The Grieving Body. Learn neuroscience-backed tips to soothe your nervous system and heal physically. Read on to learn the 4-7-8 breathing technique and simple “water rituals” that can calm your grieving nervous system and help you reclaim your sleep tonight.

Genres

Psychology, Health, Nutrition, Personal Development

Introduction: Learn how your body physically experiences grief, to better support yourself through loss.

The Grieving Body (2025) explores how bodies physically process loss, revealing the neurobiological underpinnings of grief and mourning. It advocates for developing compassionate, effective strategies that support the body through grief, recognizing that these physical manifestations are a natural part of adapting to loss.

Grief isn’t just in your heart. It lives in your racing pulse, your sleepless nights, your aching muscles, and your loss of appetite. While many resources for grief focus on the emotional healing journey, your body carries the weight of loss in ways that are rarely discussed.

This summary explores the physical experience of grief. Drawing from neuroscience and psychology, it uncovers how your nervous system, sleep patterns, and even gut function respond to profound loss. Beyond understanding these changes, you’ll also learn gentle, practical ways to support your body’s natural healing process, from breathing techniques to simple rituals that help your nervous system integrate loss over time.

If you’re navigating grief or know someone who is, this insight into the body’s wisdom provides a compassionate roadmap through territory that feels overwhelming, but is actually a natural process.

Grieving is physical

When grief enters your life, it arrives as more than just sadness or emotional pain. Grief lives in your body – in your heavy chest, in your churning stomach, in the muscles that ache with exhaustion. This physical experience is real, and yet most resources for those in grief are aimed at the emotional and mental systems, not the body.

Yet research reveals that our bodies respond to loss in predictable ways. For instance, your brain builds a detailed map of your relationship with your loved one – how they sound, smell, move, and how you interact with them. When that person is no longer present, your brain and body work overtime trying to resolve this mismatch between what they expect, and what is now reality.

This explains why you might turn to see someone who isn’t there, or why certain places or objects can trigger intense physical reactions. Your heart may race, your breathing might change, or you could feel a wave of nausea from time to time. These aren’t signs of weakness or a loss of control. They’re signs that your body is working through loss in the way humans have for millennia.

But the physical symptoms don’t stop there. Some people experience fatigue that sleep doesn’t seem to fix, changes in appetite, or tension in their shoulders or jaw. Others experience a host of digestive issues, or a feeling of heaviness in their chest that doesn’t shift. Some notice that their immune system isn’t as strong, meaning they catch every cold that goes around, while others have increasing flare-ups of existing conditions. Some people describe feeling like they’re moving through fog, or that the world looks gray, and food has lost its flavor.

When these physical sensations feel overwhelming, try placing one hand on your heart and one on your stomach. Take slow, gentle breaths, feeling the rise and fall beneath your hands. This simple action helps your nervous system feel safer in the present moment. Even just naming what you’re experiencing can help. Saying what you feel, like “my shoulders are tense” or “my chest feels tight,” can help your brain process what’s happening.

Remember that your body has profound wisdom and is trying to help you navigate this difficult time. By tuning into these physical experiences with gentleness, you begin the process of healing – not by erasing or suppressing grief, but by creating space for your body to carry it more comfortably.

The grieving system

Your nervous system is the mission control center for how your body experiences grief. When you lose someone important to you, your autonomic nervous system – the part that works without your conscious control – shifts into a protective mode. This isn’t a malfunction; it’s your body’s ancient wisdom at work.

Research has demonstrated that grief activates your sympathetic nervous system – or the fight or flight response – in the same way your body responds to danger. This explains why early grief often comes with a racing heart, shallow breathing, muscle tension, and heightened alertness. Your body is responding as if it is an emergency because, from an evolutionary perspective, separation from your tribe or loved ones was life-threatening.

At the same time, your brain releases stress hormones like cortisol and adrenaline. While these hormones help in true emergencies, their continued presence during prolonged grief can exhaust your body. This partly explains the bone-deep fatigue many people feel during grief, even when doing very little. Your body is working incredibly hard beneath the surface.

Your brain’s attachment system also plays a central role in times of grief. This system, formed through millions of years of evolution, creates powerful bonds between humans. When someone dies or leaves, this system continues searching for them. This explains the persistent yearning, the physical sensation of longing or searching that accompanies grief. Your brain is literally trying to find and reconnect with the person who’s gone.

The vagus nerve, which connects your brain to many organs, carries grief throughout your body. This explains why you might feel grief in your gut, heart, lungs, and throat. When grief is intense, your vagus nerve can trigger sensations of choking, chest pain, or digestive upheaval.

Perhaps most fascinating is how grief affects your brain’s prediction systems. Your brain constantly predicts what will happen next based on past experience. After loss, these prediction systems keep expecting to see, hear, or interact with your beloved. Each time reality conflicts with these predictions, your brain must work to update its model of the world, creating the disorienting, exhausting experience of grief.

To support your nervous system during grief, try alternating between gentle movement and rest. Even five minutes of walking, stretching, or swaying to music helps regulate your autonomic nervous system. Cold water on your face or hands can help calm an overwhelmed nervous system in moments of acute distress.

At night, a weighted blanket can provide comforting pressure that signals safety to your nervous system. During the day, notice when your shoulders creep up toward your ears – this is a sign your sympathetic nervous system is activated. Consciously lowering them while taking a deep breath sends a message of safety to your brain.

The body in distress

The disruption of your basic bodily systems is one of the most challenging aspects of grief. Three systems in particular – sleep, immunity, and digestion – undergo significant changes. The process can feel mysterious and frustrating if you don’t understand what’s happening.

Sleep patterns typically change dramatically during grief. Many people experience insomnia, struggling to fall asleep as their mind processes the loss. Others might sleep excessively but still wake feeling exhausted. This happens because grief alters your brain’s sleep architecture, including the natural progression through different sleep stages that allows for true rest and recovery.

Normally, you cycle through light sleep, deep sleep, and REM sleep. Grief tends to reduce the amount of deep and REM sleep you get, even if you’re in bed for a full eight hours. Deep sleep is when your body performs physical restoration, while REM sleep helps process emotional experiences. With less of both, you wake feeling unrefreshed, and emotional processing happens more slowly.

Your circadian rhythm, or the internal clock that regulates sleep-wake cycles, can also become disrupted. Many grieving people report being wide awake at 3 a.m., precisely when their body should be in its deepest sleep. This happens because stress hormones override your normal circadian signals, keeping you alert when you should be sleeping deeply.

Your immune system is closely intertwined with your sleep cycle and stress responses, too. Studies show that grieving individuals have reduced natural killer cell activity – these cells help fight viruses and cancer – and increased inflammatory markers throughout the body.

Your digestive system often bears the brunt of grief. The gut contains millions of neurons that communicate directly with your brain, earning it the nickname the second brain. Even the gut microbiome, or the trillions of beneficial bacteria that aid digestion, can alter during grief. This affects how you digest food and even influences your mood through the chemicals these bacteria produce. This partly explains the common experience of food losing its appeal or taste.

To support these systems, establish a gentle sleep routine by keeping consistent bedtimes and limiting screen time before bed. Rather than forcing yourself to eat large meals, try small, nutrient-dense foods throughout the day like nuts, fruit, or vegetable soups that are easier for a sensitive digestive system.

Spending time outdoors, especially in morning sunlight, helps reset your circadian rhythm and improve sleep quality. Moving your body gently during the day increases your chances of deeper sleep at night, while also supporting immune function through improved lymphatic flow.

Nurturing yourself through grief

While the process of grief might feel overwhelming, there are ways to help yourself through it. Tending to your body doesn’t mean trying to fix or eliminate grief – it’s about creating conditions that support your system as it processes this profound experience. There are some simple practices that can significantly ease the physical burden of grief, without suppressing the emotional journey.

First, your breath offers one of the most accessible pathways to soothe your nervous system. Different from basic deep breathing, specific breathing patterns can activate your parasympathetic nervous system, or your body’s normal rest and digest mode. The 4-7-8 breath pattern works particularly well during grief: inhale for a count of four, hold for seven, and exhale slowly for eight. The long exhale signals safety to your brain, and helps interrupt the stress cycle that grief initiates.

Physical touch provides another powerful avenue for healing. The skin hunger that many feel after losing a physical presence in their lives is real and physiological. Massage therapy, even just self-massaging your hands or feet, stimulates the release of oxytocin. This is a hormone that counteracts the effects of stress hormones in the body. The pressure receptors in your skin respond to weight and warmth, which is why weighted blankets or warm baths can provide deep comfort.

Nutrition takes on special importance during this process. Rather than focusing on meal schedules, just consider the nutrient density of what you eat. Foods rich in omega-3 fatty acids like walnuts, flaxseeds, and fatty fish help reduce the inflammation that grief triggers. Magnesium-rich foods like dark leafy greens, avocados, and dark chocolate support sleep and muscle relaxation. Even if you can only eat small amounts, prioritizing these foods gives your body vital resources.

Hydration affects nearly every bodily function, but grieving people often forget to drink enough. Dehydration can worsen fatigue, headaches, and cognitive fog, so keeping water visible throughout your day serves as a gentle reminder. Some people find that warm herbal teas like chamomile or lemon balm offer hydration along with mild calming effects.

Nature offers multi-system support during grief. The combination of natural light, rich sensory experience, and gentle movement creates what researchers call soft fascination, or a state where your attention is engaged but relaxed. Even brief periods outdoors can lower cortisol levels and reframe your perspective.

And remember that sound can reach parts of your brain that words can’t. Certain music, particularly pieces around 60 beats per minute, synchronizes with heart rate and breath, creating a phenomenon called entrainment. This helps regulate physical systems thrown into disarray by grief. Some also find that nature sounds like rainfall, or gentle instrumental music, give comfort without demanding emotional energy.

Rituals, hope, and healing

Creating personal grief rituals allows your body to actively participate in your healing process. Unlike cultural or religious ceremonies that happen once, personal rituals can be repeated whenever your body signals the need. Physical practices help your nervous system integrate loss over time in a healthy way.

Water rituals resonate deeply with many grieving people. The act of immersion in water – be it in the bath, shower, a lake, or the ocean – symbolizes both cleansing and transformation. The sensation of water against skin brings you into the present moment, while the flowing nature of water mirrors how grief can move through you, rather than getting stuck.

Creating with your hands engages multiple sensory systems and can bypass the cognitive overwhelm that comes with grief. Simple acts like kneading bread, shaping clay, planting seeds, or working with cloth gives your body a way to transform raw materials. This mirrors your internal process of transmuting raw grief into something you can carry.

Developing rituals around objects connected to your beloved helps your body adjust to their absence. Wearing their watch, using their coffee mug, or carrying a small object that belonged to them gives your body sensory connection while your brain adapts to the new reality. These aren’t signs of unhealthy attachment, they’re bridges that help your body make the transition.

As your body begins to heal, you’ll notice subtle shifts. Sleep may not return to normal all at once, but you might find yourself waking less frequently in the night. Your digestion might remain sensitive, but food may begin to have flavor again. These small changes are significant markers of your nervous system beginning to recalibrate.

One meaningful sign of integration is when your body can experience moments of pleasure without immediate guilt. When your body begins to accept brief periods of well-being, from enjoying the warmth of sun or the taste of a favorite food, it signals that your nervous system is expanding beyond the narrow focus of acute grief.

Another sign is the growing capacity to be present with others without exhaustion. Initially, even supportive social contact can overwhelm a grieving nervous system. As healing progresses, your body can gradually tolerate social connection again. This doesn’t mean you’re a social butterfly, just that the overwhelm subsides.

The biggest sign of healing is when memories of your loved one can live in your body alongside present-moment experiences, when feeling torn between the past with your person and the present without them starts to ease. Integration happens when your body learns to hold both the continued bond with your loved one, and your ongoing physical life, together as whole.

Conclusion

The main takeaway of this summary to The Grieving Body by Mary-Frances O’Connor is that grief manifests physically through predictable patterns in your nervous system. These patterns affect sleep, immunity, and digestion, as your brain works to reconcile the absence of someone important. Your bodily responses to grief aren’t signs of weakness but natural processes designed to help you adapt to profound change, even as they create challenging symptoms like fatigue and heightened stress responses.

Supporting your body during grief involves gentle practices like breathing techniques, good nutrition, and time in nature – all of which help regulate your nervous system and aid emotional processing. Creating personal healing rituals gives your grief tangible expression, while recognizing subtle improvements signals that integration is underway and healing has begun.