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How Relationship Conflict can Affect Your Waistline

Can bad loving cause you to pack on the pounds?

Politicians and public health officials seek to find solutions to the obesity epidemic through measures ranging from controlling sugar in your soda to shaming us into watching less TV. However, there is one contributor to obesity that until now has gone under the radar. Being in a bad relationship, as it turns out, can affect more than just your mental health. According to a large epidemiological study carried out in the United Kingdom, people who are unhappy in their current closest relationship are more likely to gain weight, and therefore a higher risk of developing obesity-related diseases.

This was not your usual correlational study in that the participants were tested over a period of years when they could reported their relationship problems at one time and were weighed at later points over the subsequent decade. The reseaerchers controlled statistically for the health status of the participants at their first time of testing to eliminate any possible effects of being heavier or more at risk due to these other factors.

The study was one of a series of follow-ups of an investigation begun in 1985, when all office staff in 20 civil service departments in London, England were tested on a range of health measures. Known as Whitehall II, this prestigious study has produced a wealth of data showing how psychosocial factors relate to health. It's thanks to Whitehall II that we have a better understanding of the mind-body connection in health and illness. We know from this study that, for example, people working in lower social class occupations experience more psychological stress which, in turn, increases their risk of dying from stress-related diseases.

One reason that Whitehall II has proven so important is that its sample size was extremely large to begin with and the measures participants completed were very comprehensive. The original study group in the relationship-obesity study consisted of over 10,000 adults ages 35-55 (6895 men and 3413 women).

It took only 4 questions to establish how much conflict participants experienced in their closest relationship. These simple questions, surprisingly, were enough to predict the extent of the ensuing weight gain among the participants. All 4 of these questions concerned the person with whom they said they had the closest relationship and all were rated on a 4-point scale, with 4 indicating more strife. See how you would rate your closest partner on these questions using the last 12 months as your reference point:

1. How much did this person give you worries, problems, and stress?

2. How much would you have liked to have confided more in this person?

3. How much did talking to this person make things worse?

4. How much would you have liked more practical help with major things from this person?

The participants rated their close relationships on these questions in the first (1985-88) and the second (1989-90) phases of the study. They were measured on their body mass index (BMI), a way to judge a person’s degree of obesity, initially, in the years 1991-94 and then a few years later, in 1997-99. Most of the participants also completed physical exams during at least one of the study phases. By the time the study was over, the research team had data spanning 11 years on approximately 8,000 participants.

University of Warsaw (Poland) researcher Anne Kouvonen and her colleagues reported on the study’s findings on obesity and relationships in a 2011 paper published in the American Journal of Public Health. You might imagine that there would be all sorts of complications in predicting a person’s weight over such a long time interval. People go through a multitude of life changes between 35 and 55 years, and almost any of them could contribute to middle-aged spread. However, with the extensive data set in Whitehall II, Kuovonen and team could rule out most of the possible complicating factors such as social class, gender, health behavior, and psychological disorders. They also used multiple time points to measure relationship problems. If you only sample people’s views about their relationship on one occasion, the results can be biased by what is going on with the couple just at that moment. Everyone can attest to the fact that the way you feel about your relationship on a Monday may not correspond to those feelings on a Saturday. By taking more than one rating into account, the Polish research team could a more stable measure of the individual’s feelings toward his or her partner.

If you’re trying to compare yourself to the study sample, here are their basic characteristics. Most of the participants were married, and about half of them worked at medium-grade occupations. They tended to have reasonably good health habits; half had never smoked, and they averaged about 3 hours of moderate physical activity a week. Over half ate fruits and vegetables on a daily basis and three-quarters had no history of mental disorder. On the relationship conflict measure, they averaged a score of just under 3.

The findings showed that the people most likely to suffer the ill effects on their weight of conflict in relationships were those initially overweight at the start of the study. Normal weight individuals showed no effect of conflict, and there were no protective effects of good relationships on weight loss. People at the highest risk for gaining weight in a bad relationships, then, were ones already at risk of possible health effects from their elevated BMIs.

What are the possible routes from bad relationship to continued weight gain? One way is through the physiological effect of constant stress on bodily systems that can make people more likely to gain weight. Being chronically unhappy in your closest relationship can also cause you to feel more negatively about your life in general, which can lead you to feel depressed and overwhelmed. Not only may your body be functioning at less than its peak ability, but you’ll be more likely to turn to food as a way to seek solace. Research on unhappily married individuals shows that they tend to go for the high-fat and high-carbohydrate “comfort food” to reduce their stress and anxiety. These high calorie foods may make people feel better at the time, but over the long run, they will only put them more at risk for further weight gain.

It’s also possible that people who are in an unhappy relationship are less likely to feel like exercising, which would then place them at risk of becoming obese. However, Kuovonen and her collaborators controlled for whether or not the participants engaged in healthy behaviors.

If you're gaining weight but don't know why, the findings from this important study suggest that you might want to take the pulse on your relationship. It’s not a matter of love or even sex that causes the need to let out your belt when things aren’t going well. Instead, it’s being able to confide in your partner, feel that your partner will help you with what you need done, and perhaps most importantly to feel that your partner can help you alleviate your stress. The next time you step on the scale and don’t like the number you read, then, don’t reach for the diet pills (they’re probably not healthy anyway). Instead, by focusing on how you and your partner can help each other cope with the stress in your life, you’ll feel happier and- in the long run- be healthier too.

Follow me on Twitter @swhitbo for daily updates on psychology, health, and aging. Feel free to join my Facebook group, "Fulfillment at Any Age," to discuss today's blog, or to ask further questions about this posting.

Copyright Susan Krauss Whitbourne, Ph.D. 2013


Kouvonen, A., Stafford, M., De Vogli, R., Shipley, M. J., Marmot, M. G., Cox, T., & ... Kivimäki, M. (2011). Negative aspects of close relationships as a predictor of increased body mass index and waist circumference: The Whitehall II Study. American Journal Of Public Health, 101(8), 1474-1480. doi:10.2105/AJPH.2010.300115

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