Being short, overweight could hinder life prospects

Increases in income do not make people more satisfied with their life
The saying goes that “you shouldn’t judge a book by its cover,” but when it comes to height and weight, a new study suggests discrimination might persist.

Published in The BMJ, the research found that people who are overweight or shorter in height might have fewer life chances than their normal-weight or taller peers.

Researchers found that people who were overweight – particularly women – had lower income and greater social deprivation.

Also, increases in income do not affect most people’s levels of life satisfaction, a study suggests.

Researchers tracked 18,000 adults over a nine-year period in the United Kingdom (U.K.) and Germany, asking them annually about their income level and how satisfied they were with life.

The current study, published in the journal Personality and Social Psychology Bulletin, accounted for shifting circumstances such as entering or leaving work, as well as changes to health and household make-up.

They found that people with higher salaries were no more likely to have a high life satisfaction than those who did not.

“It is often assumed that as our income rises, so does our life satisfaction, however, we have discovered this is not the case,” said lead researcher Dr Christopher Boyce from University of Stirling.

“What really matters is when income is lost and this is only important for people who are highly conscientious.”

Psychologists define the personality trait of conscientiousness as being very thorough in attitudes to life and work, and being efficient and organised.

Prof. Timothy Frayling, of the Institute of Biomedical and Clinical Sciences at the University of Exeter in the United Kingdom (UK), who led the BMJ study found that a higher body mass index (BMI) and shorter height may lead to lower education, poorer job status, lower income and greater social deprivation.

Previous studies have already shown that a higher socioeconomic status is linked to better health and longer lifespan. This association is believed to be partly driven by lower BMI and taller height among wealthier individuals.

“Higher socioeconomic status is generally thought to cause taller stature and lower BMI owing to higher standards of nutrition in childhood,” note the authors.

However, they argue that it is possible taller height and lower BMI “may causally improve socioeconomic status through discrimination against shorter and fatter people or differences in self-esteem that affect employability,” but evidence as to whether this might be the case is limited.
Using genetics to assess causal effect

To address this research gap, Prof. Frayling and colleagues conducted a mendelian randomization study, in which they investigated whether genetic variants that influence height or BMI may have a causal effect on socioeconomic status.

Using information from the UK Biobank study, the team analyzed the genetic data of 119,669 men and women aged 37 to 73, all of whom were of British ancestry.

The authors note that using genetic data for this study means the results are less likely to be influenced by possible confounding factors.

“Genetic variants can act as unconfounded proxies for the risk factors under investigation – here, BMI and height – because inherited genetic variation is randomly allocated at conception,” they explain. “The outcomes being tested – here, measures of socioeconomic status – cannot influence genetic variation, so reverse causality is avoided in genetic studies.”

The researchers also assessed five measures of socioeconomic status among participants: age at which full-time education was completed, degree level education, job status, annual household income and level of social deprivation – as determined by the Townsend deprivation index score.

Being overweight raises the risk of type 2 diabetes, high blood pressure, heart disease and other health problems.

The results revealed that individuals who were shorter in height – as estimated by the presence of certain genetic variants – had lower levels of education, lower job status and lower income, and this association was strongest for men.

While the researchers are unable to explain exactly why taller height appears to be associated with better socioeconomic status, they speculate that it might be down to “complex interactions” between self-esteem, stigma, positive discrimination and increased intelligence.

“Evidence shows that self-esteem, leadership perception, and height discrimination tend to be greater in men than in women, which fits with our findings,” they note.

Furthermore, participants with a higher BMI – again, as estimated by genetic data – had lower income and greater social deprivation, with this effect strongest among women.

The team suggests this finding may be down to workplace discrimination, where employees who are overweight may be viewed in a more negative light than normal-weight peers.

“The disparity between the sexes may be partially explained by discrimination, which may occur at lower weight levels for women than for men,” the authors note.

DOES MONEY BUY HAPPINESS?

The findings of this research contradict a previous study which suggested purchasing material goods gives us more frequent joy over the course of weeks and months, compared to the happiness we get from an experience.

The researchers said experiences provide intense feelings that will eventually fade, but material things remind a person about the happiness they felt when they first received it.

The University of British Columbia measured people’s happiness up to five times over a two-week period after they purchased or received something material or experiential.

But it can also be accompanied by a rigidity of thought and obsessiveness.

The research team said less conscientious individuals might attribute a loss in salary due to a lack of effort – ‘a temporary and specific cause for failure’ – whereas conscientious people, who would always be working to the best of their ability, would not be able to interpret the situation in this way.

Instead they may attribute their failure to their own lack of ability – a stable and general cause of failure,” the researchers added.

“Following the experience of negative events, such pessimistic attribution styles have been linked to lower self-esteem and increased depression.”

“Continually increasing our income is not an important factor for achieving greater happiness and well-being for most people living in economically developed countries,” said Boyce.

“To obtain greater life satisfaction we first need to move away as societies and individuals from the notion that more money leads to greater life satisfaction.

“There are other ways other than focusing on income increases that contribute more meaningfully to our life satisfaction – for example time with friends and family, looking after our mental and physical health, and obtaining a greater understanding of ourselves and trying to develop and grow.

“Unfortunately these are the things that get sacrificed in the pursuit of higher incomes.”

The team added that any income increases that can’t be sustained will be followed by falls and this may put individuals and societies in a worse place psychologically than no income increase at all.

Speaking to Medical News Today, Prof. Frayling said that while they were not surprised by the findings – noting that they already knew there was a strong link between height, BMI and socioeconomic status – the results do shed light on which direction this association goes.

He said: “Do poorer social circumstances lead to higher BMI and shorter stature, or does shorter stature and higher BMI lead to worse social circumstances, or could it be a combination of both?

“Our data provide some strong insights into this ‘chicken or egg’ problem. They suggest that something about being a little fatter or a little shorter leads to worse outcomes in life.”

However, Frayling says it is important to note that there are many very successful people who are overweight and shorter in height, noting that the findings represent a “subtle average effect.”