Let’s all go pear-shaped

[Breogan]

Let’s all go pear-shaped


In an age of obesity and anorexia it’s vital to understand the best shape and composition for our bodies

Dr Thomas Stuttaford

Before the First World War Karen Blixen, the renowned writer on Africa, was an art student at the Royal Academy in Copenhagen. She was determined to lose weight as she equated a lean figure with being interesting and bohemian, like her aristocratic cousins. Conversely, obesity represented the bourgeois solidarity that she was trying to escape. So keen was Blixen to become thin that one morning she threw her lunch-time sandwiches that her mother made out of the train window.
Karen Blixen, who was a bit chubby-faced in early adolescence, now became slim – and a depressive like her father, who later committed suicide. Blixen’s house outside Nairobi is now owned by the Kenyan state and is open to the public as a museum to commemorate her life. Photographs there show that, although the slimness she strived for produced some elegance in youth, in later years the weight loss was excessive and she was prematurely aged and withered. A museum curator said that although Blixen had other health problems her death was attributed by some to anorexia.
Dr Susan Jebb, of the Medical Research Council’s human nutrition research unit in Cambridge, warned a conference on obesity held in London this week that parents, schools and doctors did not attach enough importance to encouraging children to achieve a weight that is in the healthy middle range for preadolescents and adolescents. Achieving this would lessen their chance of suffering from cardiovascular disease or metabolic syndrome with its associated diabetes type 2, high blood pressure and several other factors when adult. An aggressive or jocular belittling approach to sensitive adolescents about being too fat or too thin could trigger a reaction that might lead to eating disorders.
Nor should family and teachers feel reassured by the thought that plump children and adolescents are only suffering from puppy fat. Dr Jebb said that neither girls nor boys should expect prepuberty fat to disappear when adolescent. The weight graph showed only a slight difference depending on their gender. Overweight girls continued to gain weight, whereas boys, although they lost a bit, remained heavier than their contemporaries.
However the body mass index (BMI), is calculated or expressed, and whether it is applied to adults or children, it gives the same message: that average weight is increasing alarmingly. International figures show that children need special attention because they are not just small adults. Moreover, people of all ages are putting on weight because the energy taken in as calories isn’t being balanced by the energy expended by exercise.
Determining the significance of the BMI is always complex. The BMI of the rawboned, heavily muscled rugby player is less medically important than that of the short, overweight apple-shaped woman, where the excess weight is carried in fat. The BMI equation is even more difficult to interpret in children, in whom the percentage of fat is different and varies when their hormones proliferate in puberty. The generalisation is that those who have an early puberty will end up fatter and shorter than those in whom it is late.
Professor Andrew Prentice, the head of the MRC International Nutrition Group at the London School of Hygiene & Tropical Medicine, said that children who were at a lesser risk of the effects of obesity tended to be those of average size when born and later grew at the same rate as their contemporaries. Trouble was more likely when children were born small but later grew faster to catch up and in the process became too fat. Professor Prentice also discussed the influence of racial differences in the determination of the BMI and its likely influence on health. A raised BMI didn’t represent, for example, the same risk for South Asians, Caucasians and African Americans. Different races stored excess fat differently and the location of the fat stores was important. It is now generally known that it is better at all times of life to be pear-shaped than apple-shaped, far better to have fat on the thighs, shoulders or buttocks than around the belly. Equally, if not more important, is the amount of fat carried in the abdomen, where visceral fat hangs from the mesenteric tissue attached to the stomach and guts. The adipose (fat) cells of visceral fat produce much of the biochemically active molecules known as adipokines. When the adipose cells become over filled with stored fat the cells secrete adipokines that can have dramatic effects on insulin resistance and production, the cardiovascular and metabolic systems.
The proportion of someone’s weight attributable to fat, although all important, is rarely calculated, although it can now easily read off the relatively inexpensive Tanita Body Composition Monitor. This look like a set of bathroom scales, but it doesn’t just weigh; it also works out what percentage of the weight is from fat, bone or muscle. The person then knows whether their weight, fat mass and body composition is similar to that of comedians Dawn French and Matt Lucas and related to fat, or Lawrence Dallaglio and his rugby colleagues whose raised BMI is a reflection of strength.


Let’s all go pear-shaped - Times Online