Bitterness: A strain on your health

Bitterness, that sharp, unpleasant flavour that makes us pucker, is not just a sensation on the tongue; it is a powerful and pervasive state of mind. From the slight resentment felt after a minor slight to the deep, corrosive anger that envelops a person’s life, bitterness is an emotional toxin with profound scientific and health implications. So, understanding it is not just about emotional management; it is a matter of personal responsibility and well-being.

In a psychological context, bitterness is defined as a prolonged, unpleasant emotional state resulting from deep grief, resentment, or disappointment. It is the feeling of being unfairly treated, cheated, betrayed, or wronged, often coupled with an unwillingness or inability to move past the perceived injury.

Although the prevalence of this emotional state is difficult to pinpoint with exact numbers, its impact is gargantuan and undeniable. Psychologists and mental health professionals recognise bitterness as a common underlying factor in various clinical issues, including chronic anger, depression, and anxiety. We see it play out in families after a dispute about a will, in former colleagues after a firing, and in individuals following a painful divorce. 

Bitterness is a universal human experience that becomes a huge problem when allowed to linger. The key to its meaning, therefore, lies in its persistence. Unlike a fleeting or brief burst of anger, bitterness is a nurtured or incubated resentment. It is anger that has settled in, soaked in rumination, and solidified into a concrete wall.

From a scientific and health perspective, bitterness is far more than an abstract feeling; it is a measurable stressor on the body. The root cause is almost always an unresolved injustice or disappointment. When a person experiences victimisation, whether from another person, an institution, or fate itself, and lacks the coping mechanisms, willingness, or resources to process the pain, the emotional wound unfortunately remains open.

This is where personal responsibility plays a crucial role. Bitterness is sustained by a person’s choice to ruminate, and ruminating means constantly replaying the hurtful event, rehearsing arguments, and fuelling a sense of being a victim. It is a mental habit that keeps the “fight-or-flight” stress response on a low, constant simmer. The underlying mechanism involves the brain’s response to stress. Sadly, persistent rumination triggers the release of cortisol (the main stress hormone) and adrenaline. While these chemicals are vital for survival, chronic exposure—which is the hallmark of persistent bitterness—is irretrievably damaging.

Now, bitterness manifests in obvious and subtle ways. This can be externally in behaviour and internally in physiology. Behaviourally, it shows up as fault-finding, perpetual complaint, and a cynical worldview. Emotionally, it leads to hostility, irritability, and an inability to genuinely celebrate the success of others. Relationally, it often results in isolation and constant focus on the past. 

Internally, the signs are much more treacherous: chronic stress, elevated blood pressure, muscle tension such as headaches and back pain, sleep disturbances, weakened immune function, and an increased risk of heart disease due to chronic inflammation. Essentially, the bitter person is living in a state of chronic, low-grade soreness. The body is constantly primed for a threat that is no longer present, and this wears down vital systems if allowed to continue over a period of time. Bitterness is, quite literally, making the person who feels offended sick.

The good news is that bitterness is not a life sentence and should not be allowed to be; it is a psychological habit that can be broken. However, this requires a conscious, often difficult, decision to shift perspective—a complete acceptance or embrace of your personal responsibility.

To prevent bitterness in the first place, there is a need to develop healthy responses to disappointment and injustice. And the starting point is developing what is regarded as emotional first aid: When hurt, process the pain immediately. Acknowledge the feeling, whether it is anger or sadness, without letting it become a story of victimhood. Then, practise cognitive reframing: Learn to challenge the narrative. Instead of “This person ruined my life,” try “This event caused me pain, but I am in charge of my recovery.” This shifts power from the injurer back to the injured. Finally, set boundaries, not vengeance: Establish healthy boundaries with the source of the pain, but do not allow the pursuit of revenge or constant re-litigation to govern your mental space.

The truth is that the ultimate solution to bitterness is forgiveness, which is often misunderstood as pardoning the person who has injured you. However, scientifically, forgiveness is an act of self-care. It is not majorly for the person who has hurt you; it is principally for you. From a neuroscientific perspective, choosing to forgive actively interrupts the stress-response cycle. It is a decision that tells the brain, “The threat is over; you can stop fighting.” This termination of the stress response lowers cortisol and adrenaline, reduces chronic inflammation, and allows the body’s systems to normalise.

The key steps to this release include acceptance—that the past event happened and cannot be changed; grief—allowing yourself to mourn the loss without letting the grief become anger; and decoupling—separating the act of injustice from your identity. Although you were hurt, always remember that you are not defined by being a victim. 

The transition from a bitter heart to a free mind is the acid test of human resilience. It is a deliberate choice to drop the heavy burden of resentment and to reclaim one’s health and future. It is a reminder that while we cannot control what happens to us, we always have control over how we allow it to shape us. Whatever you take away from this, never forget that the sweetest victory is not getting even; it is finally letting go.

I have walked that road, so I know exactly how it feels. It is certainly not an easy road, but I assure you it is a road worth walking. Let go of bitterness!  

Ojenagbon, a health communication expert and certified management trainer and consultant, lives in Lagos.