Anatomy Of A Heartbreak: Why Does It Physically Hurt?

At the moment it became clear that Sophie’s long-term partner was ending their relationship, she staggered to the bathroom and vomited profusely. "We were sitting on the end of our bed and as soon as she said the words 'I think it’s over', my body started to erupt," says the 34-year-old. "My stomach cramped like I had food poisoning. I felt like my world was falling apart."

From the moment a relationship is declared over to the following weeks and months of adjusting to life without your person, the body can feel like a war zone. Most people who have been in the mire of heartbreak will have felt pain in their body somewhere. Often it is the gut or chest. For some, it might feel diffuse, like a dull ache. For others, it may be a crushing sensation or, for people like Sophie, piercing cramps. This pain can wax and wane or be constant. However the pain shows up, it is as real as a migraine or a broken bone. Why can heartbreak cause such intense physical distress? Science offers no clear-cut answers but there are theories. 

In 2010 psychologist Professor Art Aron, neuroscientist Dr Lucy Brown and biological anthropologist Dr Helen Fisher led a study that examined the brains of heartbroken people. When participants looked at pictures or discussed the person who had rejected them, they cried, shook and got angry. With fMRI scans (measuring differences in blood flow in ‘active’ areas of the brain, appearing as vibrant blooms of blue, green, red and yellow) it was clear that the participants’ emotions triggered activity in the same brain areas associated with physical pain. "So when you say you’re ‘hurt’ as a result of being rejected by someone close to you, you’re not just leaning on a metaphor," writes Meghan Laslocky in The Little Book of Heartbreak: Love Gone Wrong Through the Ages. "As far as your brain is concerned, the pain you feel is no different from a stab wound."

I was heartbroken at the beginning of 2020. My then-partner’s timing was rather special. I was recovering from abdominal surgery, shuffling around with a stoop and unable to do much for myself. The winter of our relationship was defined by a damaging push-pull dynamic and she was right to bow out, but I had kept trying because I loved her deeply. When she left my place after delivering the blow, I wept myself empty on the sofa while my dog licked my cheeks. In the subsequent weeks, it was hard to tell what was post-surgery discomfort and what was the pain of heartbreak. But when I thought of her, of us, I felt a murky heaviness in my gut. As I texted a friend at the time, it felt like my belly was full of algae. My usually raging appetite dissolved. I had cereal for dinner more times than I’d care to remember.

Loss of appetite seems to be a common feature of heartbreak. Sam, 28, tells me she "barely ate for weeks" following a breakup last year. "I knew that I should eat but had no cravings whatsoever. When I put food in my mouth, I would immediately feel sick. It was like my body was rejecting the sustenance, as though it wanted me to suffer." Sam lost almost 6kg in the space of three weeks. "I remember looking in the mirror and thinking that the gap between my stomach and my waistband reflected the loss I was feeling." As we talk, I ask her where she felt the pain the most. She instinctively places her hands on the top of her belly, just under her diaphragm. "Here," she says. "It was awful."

Many people I have spoken to about heartbreak have held their bodies similarly. It feels primitive, speaking to a core pain we experience as human beings. Purely anecdotally, I have heard women speaking more of this physical distress following heartbreak than men. Over 90% of cases of the rare condition broken heart syndrome are women. Known as Takotsubo syndrome (TTS), the heart’s left ventricle (the main pumping chamber) weakens as a result of severe emotional stress. The loss of a loved one, through death or separation, is a known cause. Everyone, irrespective of gender, holds a world of unconscious expectations about how relationships ‘should’ be. But scientists are researching the stark sex difference in TTS and why loss can be so devastating to women’s bodies. As one Forbes article asks: "Could it be due to differences in societal expectations and systems that may be putting more pressure on women or paying less attention to their situations?"

Physical symptoms like loss of appetite, digestive or skin issues, headaches and insomnia following a breakup may speak to the triggering of one of our most primitive bodily systems: the fight-or-flight response. In response to a threat, lightning-fast hormonal changes activate the sympathetic nervous system. Physiological changes like increased blood flow to the muscles (which can cause trembling), increased heartbeat and respiration rate (flooding the body with oxygen) and pupil dilation (letting in more light to see our surroundings better) equip us to fight the threat or flee to safety. Unfortunately, the brain often hits this accelerator in reaction to situations that are not life-threatening. As Brown, co-author of the 2010 heartbreak study tells me, "Nature overdid it a little bit".

Losing a relationship can be experienced as a threat to our sense of self, particularly if we are the ones being rejected. In this sense, the pain is quite existential. (In one study, people used fewer unique words to describe themselves when reflecting on a breakup.) "Being rejected is so painful because it is a loss of self. You are not just losing a person but your daily habits, a sense of protection and a big reward," says Brown. "Your brain reward system has been activated again and again by this person, so you feel lost. Neural pathways are so strongly laid down in a relationship – we are driven to keep it going. People talk about their worlds being shattered and they are, because everyday life has changed."

Brown, a neuroscientist, was one of the first scientists to posit the idea of love as a ‘natural’ addiction. All her 15 heartbroken study participants reported thinking about their ex-partner over 85% per cent of the time, with an extreme yearning to be with them again. Turning up at an ex’s home or workplace to express despair was common, along with pleading phone calls and emails. This behaviour mirrors drug cravings. In the fMRI scanner, when participants looked at pictures of their ex, brain regions were activated that ‘light up’ in those addicted to — and craving — drugs like cocaine. However, love is not hijacking addiction circuitry. 

Being in love is tied to reward systems involving dopamine, oxytocin and serotonin, which play a role in the development of trust, safety, and warmth — all the good stuff of romantic relationships. Drugs exploit these reward systems. Just like an experience with drugs, romantic love can start with euphoria and end in craving. This craving often involves ploughing memories of the person we’ve lost. With each recall comes a new wave of pain. At several points in 2020, particularly in the isolation of lockdown, I longed to erase my memories. I have learned that, for me, the best way to quieten the mind is through moving the body, so walking and gentle yoga helped. But I also had the delicious fantasy of being given a general anaesthetic — of total wipeout. 

In 2019 a Spanish study was published that found propofol — the sedative used for anaesthesia — may help soften the painful memories that accompany heartbreak. Participants were injected with propofol immediately after recalling a distressing memory. When asked to repeat it a day later, the memory was less vivid. The research goal was to help relieve symptoms of PTSD but the authors suggested scope for other distressing memories. The ethical problems of giving sedatives to the heartbroken would be enormous. We know very little about the complications that may arise from tampering with emotional memories. Brown also argues that heartbreak has an evolutionary function.

"Heartbreak has some utility for your survival," she explains. "The ‘social pain’ of the separation speaks to a deep motivation our primitive ancestors would have had to find a mate for protection." The same danger is not all that relevant to the modern world. When we recover from heartbreak, we build new routines and social connections to help us cope, and then evolve. The pain is what focuses our attention to get support, learn and move on. No drug can serve this function; we have to do it ourselves. "You are supposed to feel bad because you're supposed to learn something," says Brown. I’m reminded of something Zadie Smith writes in White Teeth: "You are never stronger … than when you land on the other side of despair." 

Then there is bereavement: a unique kind of heartbreak, where there is no "what if?" for the brain to ponder about reconciling. The loss is unequivocal. Seeing a function in this despair might feel like a tall order. Physical symptoms of grief overlap with the heartbreak of a lost romantic relationship, speaking to the same core reality: emotion lives in the body in profoundly physical ways. 

My friend Rosie spent two years caring for her mother, Sarah, when she became ill with cancer. Rosie’s dedication, along with the knowing humour between her and Sarah in the face of such pain — right to the end — is one of the most beautiful things I have witnessed. Sarah died in August. "I told myself when we arrived at the hospice: 'I am heartbroken but I am okay. Here we are. I surrender,'" says Rosie. "When she died I felt my heart break into a million pieces and it’s still shattered." Four months on, she describes the physical feeling as "somebody taking a cheese grater to my innards; nausea that comes from total vulnerability and rawness". Regular therapy and being around close friends is helping her "deal with the sense of crisis" but she knows there is "no getting around this period of heartbreak''. It is a necessary pain. 

It is understandable that anyone in the throes of grief might long for a bodily "stop" button. Gina, 33, tells me that when her sister died in 2012, insomnia "made each day feel like living torture". She was exhausted but wired, "lying awake until 4am most nights, then struggling with nausea and anxiety the next day". Her GP prescribed a short course of strong sleeping pills and referred her for bereavement counselling. Gina describes the pills as "a temporary godsend" but credits the counselling for "helping me process the overwhelming emotions".

It may be nature’s plan for us to feel pain; to sit with it and process what went wrong after a breakup so that we don’t repeat the same mistakes, or know what we need next time around. But the plan doesn’t make the pain less awful. If we are grieving someone who has died, the process is somewhat different; loss has to be gradually integrated into life. But it moves, gradually, particularly through meaningful connections with other people. As human beings, we have the capacity to hurt terribly but we are built to evolve. The only thing bigger than pain is time.