Sheila Graham
Obesity is increasing rapidly throughout the developed world. In some countries rates have doubled in just a few years. Obesity is measured by Body Mass Index (BMI)* to take height into account and avoid labelling people as overweight just because they are tall. The World Health Organization has set standards for using BMI to classify people as underweight (BMI < 18.5), normal weight (BMI 18.5–24.9), overweight (BMI 25–29.9) and obese (BMI >30). In the USA, in the late 1970s, close to half the population were overweight and 15 per cent were obese; now three-quarters of the population are overweight, and close to a third are obese. In the UK in 1980, about 40 per cent of the population were overweight and less than 10 per cent were obese; now two-thirds of adults are overweight and more than a fifth are obese. 97–100 This is a major health crisis, because obesity is so bad for health – it increases the risk of hypertension, type II diabetes, cardiovascular disease, gallbladder disease and some cancers. Trends in childhood obesity are now so serious that they are widely expected to lead to shorter life expectancies for today’s children. That would be the first reversal in life expectancy in many developed countries since governments started keeping track in the nineteenth century.101
Apart from the health consequences, obesity reduces emotional and social wellbeing: overweight and obese adults and children suffer terribly. A 17-year-old from Illinois, weighing 409 lb (29 stone) described her physical pain: ‘my heart aches in my chest and I have arm pains and stuff and it gets scary’.102 But just as hurtful are the memories she has of other children calling her names at school, her restricted social life and her feeling that her body is ‘almost a prison to me’.
Britain’s tabloid newspaper, the Sun, featured three obese children in the spring of 2007.103–105 The youngest, a boy aged 8, weighed 218 lb (15.5 stone) and was being bullied at school – when he attended. His weight was so great that he often missed school due to his difficulties in walking there and back, and was exempt from wearing school uniform because none was available to fit him. His elder sister, aged 9, weighed 196 lb (14 stone) and was also being bullied and teased, by both children and adults. She said she found it ‘hard to breathe sometimes’, and did not like ‘having to wear ugly clothes’ and being unable to fit on the rides at amusement parks. Heaviest was the oldest boy who, at the age of 12, weighed 280 lbs (20 stone). He was desperately unhappy – expelled from two schools and suspended from a third, for lashing out at children who called him names.
THE ‘OBESOGENIC’ ENVIRONMENT
Many people believe that obesity is genetically determined, and genes do undoubtedly play a role in how susceptible different individuals are to becoming overweight. But the sudden rapid increase in obesity in many societies cannot be explained by genetic factors. The obesity epidemic is caused by changes in how we live. People often point to the changes in cost, ease of preparation and availability of energy-dense foods, to the spread of fast-food restaurants, the development of the microwave, and the decline in cooking skills. Others point to the decline in physical activity, both at work and in leisure time, increasing car use and the reduction in physical education programmes in schools. Modern life, it seems, conspires to make us fat. If there was no more to it than that, then we might expect to see more obesity among richer people, who are able to buy more food, more cars, etc., and high levels of obesity in all wealthy societies.
But this is not what happens. During the epidemiological transition, which we discussed in Chapters 1 and 6, in which chronic diseases replaced infectious diseases as the leading causes of death, obesity changed its social distribution. In the past the rich were fat and the poor were thin, but in developed countries these patterns are now reversed.106 The World Health Organization set up a study in the 1980s to monitor trends in cardiovascular diseases, and the risk factors for these diseases, including obesity, in twenty-six countries. It found that, as rates of obesity have increased, their social gradient has steepened.107 By the early 1990s obesity was more common among poorer women, compared to richer women, in all twenty-six countries, and among poorer men in all except five. As journalist Polly Toynbee declared in a newspaper article in 2004: ‘Fat is a class issue.’108 Pointing to the high rates of obesity in the USA and the low rates among the Scandinavian countries, which prove that we don’t find high levels of obesity in all modern, rich societies, she suggested that income inequality might contribute to the obesity epidemic.
INCOME INEQUALITY AND OBESITY
Figure 7.1 shows that levels of obesity tend to be lower in countries where income differences are smaller. The data on obesity come from the International Obesity Task Force and show the proportion of the adult population, both men and women, who are obese – a Body Mass Index (BMI) of more than 30.109
The differences between countries are large. In the USA, just over 30 per cent of adults are obese; a level more than twelve times higher than Japan, where only 2.4 per cent of adults are obese. Because these figures are for BMI, not just weight, they’re not due to differences in average height.
Figure 7.1 More adults are obese in more unequal countries.
The same pattern can be seen internationally for children (Figure 7.2). Our figures on the percentage of young people aged 13 and 15 who are overweight, reported in the 2007 UNICEF report on child wellbeing, came originally from the World Health Organization’s Health Behaviour in School-age Children survey.110 There are no data for Australia, New Zealand or Japan from this survey, but the relationship with inequality is still strong enough to be sure it is not due to chance. The differences between countries are smaller for overweight children than for adult obesity. In the country with the lowest level, the Netherlands, 7.6 per cent of children aged 13 and 15 are overweight, which is one-third the rate in the USA, where 25.1 per cent are overweight. (As these figures are based on children reporting their height and weight, rather than being measured, the true prevalence of overweight is probably higher in all countries, but that shouldn’t make much difference to how they are related to inequality.)
Within the USA, there are no states with levels of adult obesity lower than 20 per cent. Colorado has the lowest obesity prevalence, at 21.5 per cent, compared to 34 per cent in Texas, which has the highest.* But the relationship with inequality is still strong enough for us to be confident it isn’t due to chance. Other researchers have found similar relationships. One study found that higher state-income inequality was associated with abdominal weight gain in men,111 others have found that income inequality increases the risk of inactive lifestyles.112 Overweight among the poor seems to be particularly strongly associated with income inequality.
Figure 7.2 More children are overweight in more unequal countries.
For children in the USA, we obtained data from the National Survey of Children’s Health (Figure 7.4). Just as for the international figures for children, these data are for overweight (rather than obese) children, aged 10–17 years. (The child’s height and weight are reported by the parent, or the adult who knows the child best.) The relationship with inequality is even stronger for children than for adults.
Figure 7.3 More adults are obese in more unequal US states.113
Figure 7.4 More children are overweight in more unequal US states.
EATING FOR COMFORT . . .
The pathways linking income inequality to obesity are likely to include calorie intake and physical activity. Indeed, our own research has shown that per capita calorie intake is higher in more unequal countries. This explained part of the relationship between inequality and obesity, but less for women than for men.114 Other researchers have shown that income inequality in US states is related to physical inactivity.112 It seems that people in more unequal societies are eating more and exercising less. But in studies in Australia, the UK and Sweden the amount that people eat, and the amount of exercise they do, fails to fully account for social class differences in weight gain and obesity.115–118
Calorie intake and exercise are only part
of the story. People with a long history of stress seem to respond to food in different ways from people who are not stressed. Their bodies respond by depositing fat particularly round the middle, in the abdomen, rather than lower down on hips and thighs.119–120 As we saw in Chapter 6, chronic stress affects the action of the hormone cortisol, and researchers have found differences in cortisol and psychological vulnerability to stress tests among men and women with high levels of abdominal fat. People who accumulate fat around the middle are at particularly high risk of obesity-associated illnesses.
The body’s stress reaction causes another problem. Not only does it make us put on weight in the worst places, it can also increase our food intake and change our food choices, a pattern known as stress-eating or eating for comfort. In experiments with rats, when the animals are stressed they eat more sugar and fat. People who are chronically stressed tend either to over-eat and gain weight, or under-eat and lose weight. In a study in Finland, people whose eating was driven by stress ate sausages, hamburgers, pizza and chocolate, and drank more alcohol than other people.121 Scientists are starting to understand how comfort eating may be a way we cope with particular changes in our physiology when we are chronically stressed, changes that go with feelings of anxiety.122
The three obese children featured in the Sun newspaper, whom we described earlier, all seemed to have turned to comfort eating to deal with family break-ups. The nine-year-old girl said, ‘Chocolate is the only thing I’m interested in. It’s the only thing I live for . . . when I’m sad and worried I just eat.’ Her older brother gained 210 pounds (15 stone) in five years, after his parents divorced.
A number of years ago, the Wall Street Journal ran a series, ‘Deadly Diet’, on the nutrition problems of America’s inner cities.123 Among the overweight people they interviewed was a 13-year-old girl living in a violent housing project (estate), who said that food and TV were a way of calming her nerves. An unemployed woman who knew that her diet and drinking were damaging her liver and arteries, still figured she ‘might as well live high on the hog’ while she could. A grandmother bringing up her grandchildren because of her daughter’s addiction to crack cocaine, said:
Before I was so upset that my daughter was on this crack I couldn’t eat. I turned to Pepsi – it was like a drug for me. I couldn’t function without it. I used to wake up with a Pepsi in my hand. A three-liter bottle would just see me through the day.
Recent research suggests that food stimulates the brains of chronic over-eaters in just the same ways that drugs stimulate the brains of addicts.124–126 Studies using brain scans have shown that obese people respond both to food and to feeling full differently from thin people.127
. . . EATING (OR NOT) FOR STATUS
But food choices and diets aren’t just dictated by the way we feel – they’re also patterned by social factors. We make food choices for complicated cultural reasons – sometimes we like foods we grew up eating, which represent home to us, sometimes we want foods that represent a lifestyle we’re trying to achieve. We offer food to other people to show that we love them, or to show that we’re sophisticated, or that we can afford to be generous. Food has probably always played this role; it’s the necessary component of the feast, with all of its social meanings. But now, with the easy availability of cheap, energy-dense foods, whatever social benefits might come from frequent feasting, they are, so to speak, outweighed by the drawbacks.
In the Wall Street Journal’s ‘Deadly Diet’ series, a recent immigrant from Puerto Rico describes how her family used to live on an unchanging diet of rice, beans, vegetables, pork and dried fish. Since moving to Chicago, they have enjoyed fizzy drinks, pizza, hamburgers, sugared breakfast cereals, hotdogs and ice-cream. ‘I can’t afford to buy the children expensive shoes or dresses . . . but food is easier so I let them eat whatever they want.’ Most of all, the family enjoy going to fast-food restaurants and eat out twice a month, although the children would like to go more often. ‘We feel good when we go to those places . . . we feel like we’re Americans, that we’re here and we belong here.’
A 17-year-old in New Jersey described how being able to buy fast food proves your financial status, shows that you have money in your pocket and are not having to wait for the welfare cheque at the end of the month.
A 37-year-old man said he spent half his wages on fast food. On the day he was interviewed he had been to McDonalds three times and was planning to go to Kentucky Fried Chicken and a Chinese take-out shop before the day was out. But the fast-food restaurants had a meaning for him that went well beyond the cheap food. Despite working, he was homeless and they had become his sanctuary:
He has no home of his own and shuttles between his aunt’s place in Brooklyn and a friend’s apartment in a Harlem housing project [estate]. ‘The atmosphere makes me feel comfortable and relaxed and you don’t have to rush,’ he says as he admires the hamburger restaurant’s shiny floors and the picture of George Washington Carver [a famous nineteenth-century black American] on a wall. Lulled by the soft piped-in music, he nods off for a moment and then adds: ‘ain’t no hip-hop, ain’t no profanity. The picture, the plants, the way people keep things neat here, it makes you feel like you’re in civilization.’
A member of a Hispanic street gang eats all his meals at fast-food restaurants, boasting that he hasn’t eaten a meal at home since he was 16:
Kids here don’t want to eat their mother’s food . . . everyone is tired of their mother’s food – rice and beans over and over. I wanted to live the life of a man. Fast food gets you status and respect.
FAT IS A FEMININE ISSUE?
Our own work, like the studies of other researchers, shows that the relation between income inequality and obesity is stronger for women than for men. In the World Health Organization’s study in twenty-six countries the social gradient in obesity is seen more consistently, and tends to be steeper, for women than for men. In the 2003 Health Survey for England, the positive association between low socio-economic status and obesity is very clear for women but among men there is no association.128
It might be that these patterns result from obesity having a stronger negative effect on social mobility for women, than for men. Maybe obese young women suffer more discrimination in labour markets and the marriage market, than obese young men. Or maybe low social status is more of a risk factor for obesity in women than in men. Two studies within British birth ‘cohorts’ offer some clues. These studies are surveys of large samples of people born at the same time, and followed from birth. A study of people born in 1946 found that upwardly mobile men and women were less likely to be obese than those whose social class didn’t change between childhood and adulthood.129 In the 1970 cohort obese women, but not men, were more likely never to have had gainful employment and not to have a partner.130
In the USA and in Britain, female obesity in adolescence has been linked to lower earnings in adulthood.131–132 Although not limited to women, a recent survey of more than 2,000 Human Resource professionals found that 93 per cent would favour a normal-weight job applicant over an equally qualified overweight candidate. Nearly 50 per cent of these professionals felt that overweight people were less productive; almost 33 per cent felt that obesity was a valid reason not to hire somebody; and 40 per cent felt that overweight people lacked self-discipline.133
Although being overweight clearly hampers social mobility, our own analysis of trends within women born in Britain in 1970 suggests that this doesn’t explain the social gradient in obesity among women and, even in middle age, low social class is linked to weight gain.117
YOU CAN NEVER BE TOO RICH OR TOO THIN
Social class differences in the importance of body size and in the body image towards which women aspire also seem to contribute to the social gradient in obesity. In the past, women with voluptuous bodies were much admired, but in many modern, richer cultures, being thin signals high social class and attractiveness. British women in higher social classes are more likely to m
onitor their weight and to be dieting than women in lower social class groups, and are also more dissatisfied with their bodies.134 Women who move down the social scale seem to place less emphasis on thinness and are more satisfied with their bodies. Changes in marital status also play a role: in a US study, women who married gained more weight than women who remained single or women who divorced or separated.135 And not all women want to be thin – for example in inner-city African-American communities, thinness can be associated with an image of poverty, hunger and being on welfare, as well as AIDS and drug addiction. As one 19-year-old woman put it:
I’ve been a voluptuous female all my life. If I start losing a lot of weight, people will think I’m on drugs . . . in the ghetto, you just can’t afford to look too thin.
Her words are a reminder of the ways in which social class is related to being overweight in the developing world, where only the affluent can afford to be fat. In wealthy countries, it looks as if women in higher social classes are more likely to have aspirations to thinness and be more able to achieve them.
But while women’s body weight may be most affected by social factors, men are certainly not immune. A recent 12-year study of working-age men in the USA found that if they became unemployed, they gained weight.136 When their annual income dropped they gained, on average, 5.5 lbs.
THE THRIFTY PHENOTYPE
One additional idea that suggests a causal link between higher levels of income inequality in a society and higher body weights is known as the ‘thrifty phenotype’ hypothesis. Put simply, this theory suggests that when a pregnant woman is stressed, the development of her unborn child is modified to prepare it for life in a stressful environment. It isn’t yet clear whether stress hormones themselves do the damage, or whether stressed foetuses are less well nourished, or both things happen, but these ‘thrifty phenotype’ babies have a lower birthweight and a lower metabolic rate. In other words, they are adapted for an environment where food is scarce – they are small and need less food. In conditions of scarcity during our evolutionary past this adaptation would have been beneficial, but in our modern world, where stress during pregnancy is unlikely to be due to food shortages and babies are born into a world of plenty, it’s maladaptive. Babies with a thirfty phenotype in a world where food is plentiful are more prone to obesity, to diabetes and to cardiovascular disease. As this book shows, societies with higher levels of income inequality have higher levels of mistrust, illness, status insecurity, violence and other stressors, so the thrifty phenotype may well be contributing to the high prevalence of obesity in them.
The Spirit Level: Why Greater Equality Makes Societies Stronger Page 9