Unhappy Marriages and Heart Disease: How Relationship Stress Can Literally Break Your Heart

Wednesday, March 19, 2025.

Is there a link between marital conflict and cardiovascular health?

For years, we've known that stress is bad for the heart.

But what if the most damaging stressor in your life isn't your job, financial concerns, or even your in-laws—but your marriage?

A study of 1,200 older married adults (ages 57-85) led by sociologist Hui Liu at Michigan State University found that people in unhappy marriages, particularly women, have an increased risk of heart disease compared to those in satisfying marriages (Liu et al., 2016).

These findings aren't just a warning sign for those in rocky relationships; they reveal a critical intersection between mental and physical health.

The study, published in the Journal of Health and Social Behavior, used a multi-faceted approach, analyzing survey responses about marital quality alongside laboratory tests measuring heart health and self-reports on heart attacks, strokes, hypertension, and other cardiovascular risk factors. The results were clear: an unhealthy marriage isn't just emotionally draining—it can be physiologically damaging.

Marriage and the Heart: What the Research Says

Liu’s study isn’t an isolated finding. Decades of research have linked relationship stress to poor cardiovascular outcomes. In fact, the quality of a marriage can be a stronger predictor of heart disease than traditional risk factors like smoking or high cholesterol (Robles et al., 2014). Let’s break down the major takeaways:

The "Four Horsemen" of Heart Disease: Criticism, Contempt, Defensiveness, and Stonewalling

If you've ever studied relationship science, you've likely encountered the work of Drs. John and Julie Gottman. Their research on marital stability and divorce prediction highlights four toxic behaviors—criticism, contempt, defensiveness, and stonewalling—that predict relational breakdown (Gottman & Silver, 1999).

Liu’s study suggests that these same behaviors, when persistent over time, don’t just lead to breakups; they lead to heart attacks.

When partners treat each other poorly—through persistent demands, hostility, or emotional neglect—stress hormone levels skyrocket, contributing to increased blood pressure and systemic inflammation, both of which raise the risk of cardiovascular disease (Kiecolt-Glaser & Wilson, 2017).

The Longer the Marriage, the Worse the Damage

The negative impact of an unhappy marriage isn’t equally distributed across all age groups—it accumulates over time. Liu’s research found that older adults experience more severe cardiovascular consequences from marital stress than younger couples.

Why? As we age, our immune function weakens, and our body’s ability to recover from stress diminishes.

Chronic marital conflict triggers prolonged inflammatory responses, leading to plaque buildup in arteries, hypertension, and increased cardiac events (Liu et al., 2016). In other words, a bad marriage doesn’t just feel bad—it wears down the body’s resilience over time, making it harder to bounce back from physiological damage.

Women Are More Vulnerable Than Men

One of the most striking findings in Liu’s study is that women in unhappy marriages are more likely to suffer heart disease than men in similarly unhappy relationships.

The reason? Women are more likely to internalize negative emotions and somaticize stress, meaning they carry relational distress within their bodies (Gouin et al., 2009). While men often externalize stress through risk-taking behaviors (such as drinking or avoidance), women’s bodies take the brunt of long-term emotional turmoil, often manifesting in increased inflammation, hormonal imbalances, and autonomic nervous system dysregulation—all of which increase cardiovascular risk.

This finding is particularly important because traditional heart disease prevention strategies often focus on diet, exercise, and medical interventions—but fail to address relational stress as a major risk factor.

The Good News: Your Marriage Can Be Your Heart’s Best Medicine

If you’ve read this far and started clutching your chest in mild panic, take a deep breath—because here’s the good news: you can change your marriage, and in doing so, you can protect your heart.

While the negative effects of a toxic relationship are strong, the positive effects of a healthy, supportive marriage are equally powerful. Research shows that people in high-quality marriages have significantly lower rates of heart disease, lower blood pressure, and stronger immune systems (Robles et al., 2014).

How Relationship Science Has Transformed Couples Therapy

Traditionally, marriage counseling was based on talk therapy—learning to communicate better, listen more, and maybe argue less. But in recent decades, our understanding of relationships has deepened thanks to advancements in neuroscience, attachment theory, and psychobiology.

A new generation of relationship therapies focuses not just on talk therapy, but on retraining the nervous system and creating secure emotional bonds. Interventions for re-wiring the nervous system are the next big thing in marriage and family therapy. There are many such approaches, I’ve also developed new interventions myself, but they all share a common scope of work:

• Communicate in ways that de-escalate stress and foster safety. Manage the moment with skill and presence.

• Understand each other’s nervous systems to regulate emotional responses. Promote awareness of regulation and co-regulation.

• Develop attachment rituals that create a sense of security and belonging. Small acts of kindness. often.

Research suggests that when couples actively work on regulating each other’s nervous systems, their bodies shift from a state of hypervigilance (which taxes the cardiovascular system) into a state of safety and connection (Tatkin, 2011).

Simply put: when your marriage feels safe, your heart gets a break.

Can Science-Based Couples Therapy Reduce Heart Disease?

Surprisingly, relationship counseling may be just as effective for heart health as lifestyle changes like quitting smoking or improving diet.

A meta-analysis of 39 studies found that couples who engage in structured relationship therapy experience reduced blood pressure, lower cortisol levels, and even improved cholesterol profiles (Slatcher et al., 2015). The effect was strongest for women in previously distressed marriages. Science-based couples therapy is good heart medicine.

Protect Your Heart by Healing Your Relationship

If you’ve been in a high-stress marriage for years, your body has likely been in survival mode, constantly flooded with stress hormones that are silently damaging your cardiovascular system. But research shows that it’s never too late to turn things around.

By repairing attachment wounds, learning to co-regulate stress, and fostering secure emotional connections, couples can reduce their risk of heart disease and even reverse some of the damage already done.

So after you schedule that cardiology appointment, consider scheduling a free meet & greet session with me.

Your heart—not just your relationship—might depend on it.

Be Well, Stay Kind, and Godspeed.

REFERENCES:

Gottman, J. M., & Silver, N. (1999). The seven principles for making marriage work. Crown Publishers.

Gouin, J. P., Carter, C. S., Pournajafi-Nazarloo, H., Malarkey, W. B., Loving, T. J., Stowell, J., & Kiecolt-Glaser, J. K. (2009). Marital behavior, oxytocin, vasopressin, and wound healing. Psychoneuroendocrinology, 34(10), 1506-1512. https://doi.org/10.1016/j.psyneuen.2009.05.010

Kiecolt-Glaser, J. K., & Wilson, S. J. (2017). Lovesick: How couples’ relationships influence health. Annual Review of Clinical Psychology, 13, 421-443. https://doi.org/10.1146/annurev-clinpsy-032816-045111

Liu, H., Waite, L. J., Shen, S., & Wang, D. H. (2016). Bad marriage, broken heart? Age and gender differences in the link between marital quality and cardiovascular risks among older adults. Journal of Health and Social Behavior, 57(4), 420-435. https://doi.org/10.1177/0022146516671056

Robles, T. F., Slatcher, R. B., Trombello, J. M., & McGinn, M. M. (2014). Marital quality and health: A meta-analytic review. Psychological Bulletin, 140(1), 140-187. https://doi.org/10.1037/a0031859

Tatkin, S. (2011). Wired for love. New Harbinger Publications.