LOVE, AS WE ALL KNOW, HURTS. You get the love bug, then love sick, and then your heart breaks. Our very language reflects the emotional links we make between our relationships and our state of health.

But researchers now have evidence that the link is more than poetic fancy. The state of our relationship actually does affect our physical health — and not just because of the sleeplessness and poor diet that unhappiness brings. The link is so strong that it affects how rapidly our wounds heal and how well we fight off disease.

For more than 20 years Dr Janice Kiecolt-Glaser and Dr Ronald Glaser, a husband and wife team from Ohio State University, have studied the ways in which stress affects our bodies. In their most recent study the Glasers, a psychologist and immunologist respectively, have found that the way couples deal with conflict has an important effect on their physical wellbeing.

The researchers looked at 90 couples in their first year of marriage: newlyweds were encouraged to discuss subjects known to be a source of disagreement to them — the in-laws, whether to have a baby, money, working late.

During the often-heated discussions, the couples were videotaped and their arguments were given scores for aggressive or negative behaviour. They also had their blood tested throughout to measure stress hormone levels and immune system activity. Wound-healing was also monitored (using equipment attached to specially created blisters on their arms).

Negative behaviour during arguments, particularly criticism, sarcasm and put-downs, resulted in a weakened immune response (measured in activity of one type of white blood cell, T lymphocytes, which works to attack viruses), as well as increased levels of the stress hormones adrenalin, noradrenalin, cortisol and adrenocorticotropic hormone (ACTH) — substances that can further reduce immunity. The researchers also found that in the blisters on the couples’ arms, concentrations of compounds called cytokines and cells called neutrophils, which aid healing and fight infection, were lower in couples who argued aggressively. Measurements over time showed that they healed slower.

“The people who got nasty and didn’t fight well showed greater physiological changes,” says Glaser, who is professor in molecular virology, immunology and medical genetics at the Ohio State University Medical Centre. “It was especially true in women, who have a remarkable way of storing data and then using it in an argument. The men tended to stonewall.”

The researchers say that these physical changes brought on by conflict in a relationship may make people susceptible to illness, particularly infectious diseases, perhaps even cancer. The Glasers’ earlier work had shown that in people whose immune response was impaired by stress, there was greater chance that anti-flu jabs and other vaccinations wouldn’t work.

“There’s no doubt that different emotions produce different physiological changes in the body, and they vary to some degree depending on the emotion,” Glaser says.

The effects are not short-term. The Glasers followed up their couples ten years later to see how their marriages had fared. Most of those who had argued negatively and who had shown high levels of stress hormones were separated or dissatisfied with their marriages.

At the most superficial level, the research may explain why our lives generally seem to be falling apart when our relationships are going badly — on a physical level we become less able to cope. But its real importance is that it adds authority to a growing body of research showing that the everyday stresses that we experience from our work and relationships have a direct, rather than merely indirect, impact on our health. An influential study published in the British Medical Journal a few years ago, for example, found that depression, anxiety and lack of social support (of the type provided by a secure relationship) all appeared to contribute to coronary heart disease. But dozens of other articles published in the past decade have also provided evidence that unhappy marriages have a negative effect on the circulatory, hormonal, immune and nervous systems. Predictably, a study found that the risk of mental illness increased tenfold when there was marital discord. But studies have also found a link with tooth decay, rheumatoid arthritis and blood pressure.

The rigour of some of these studies might be questioned — there is an argument that they reflect the characteristics of the social section being sampled as much as a causative link. But what is clear and uncontested is that a good relationship is good for you. On average, married people — whether happy or unhappy — enjoy better mental and physical health than the unmarried, and women in particular seem to benefit from a good-quality marriage. One 15-year study has indicated that, for women, companionship in marriage and equality in decision-making were associated with a lower risk of death.

The lesson for all of us is that once you find love, you should make sure that you respond to the inevitable conflicts constructively and not aggressively –— the consequences could be physical as well as emotional. As a partnership at work and home, the Glasers have been careful to heed the lessons of their research. They don’t tend to argue much because they spend a lot of time at home talking about their work. “It works pretty well since we’re both pretty driven type A personalities. It might be different if one of us wanted to turn off,” Ron Glaser says.

Love links

Centre for Stress and Wound Healing, Ohio State University
www.med.ohio-state.edu/mindbody/kiecolt_glaser.html

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