Cardiovascular Journal of Africa: Vol 28 No 5 (September/October 2017)

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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 28, No 5, September/October 2017 AFRICA 279
Who is too fat?
Julien IE Hoffman
Obesity is a modern pandemic that, if not checked, will lead to
increased rates of morbidity and mortality from type 2 diabetes,
cardiovascular disease, cancer, osteoarthritis, hypertension,
and other complications.1-3 In Tonga, a country with one of
the highest percentages of obese people in the world, the
recent further increase in incidence of obesity has reduced life
expectancy from the mid-70s to the mid-60s.1 In the USA, older
people with a body mass index (BMI) of 40 kg/m2 had an almost
four-fold increased mortality rate compared with those with a
BMI of 25 kg/m2.4
A well-executed study by Macia et al.,5 published in this
edition of the journal, explores some of the factors involved in
the obesity pandemic. They examined adults in a rural area in
Senegal and compared them with adults in the capital, Dakar.
One of the main findings was that there was more overweight
and central obesity in the urban than the rural area, and this was
attributed to the reduced amount of exercise and higher calorie
intake by urban dwellers.
The second important finding was based on showing the
subjects silhouettes of people varying from the very obese to
the very thin, and asking them what they thought about their
weight. Men were more satisfied with their weight than were
women. The weight selected as ideal was higher in the rural than
the urban area, and for women in the rural area, their perceived
ideal weight fell into the overweight category.
In many parts of the world there is improved social status
in being fat. This attitude is not confined to underdeveloped
countries. In the United Kingdom from 1999 to 2007, the
percentage of obese people increased but the proportion who
identified themselves as being overweight or obese decreased.6
How should we control this pandemic? First, we need to
decide who needs treatment. In 1944 Cyril Connolly wrote
‘Imprisoned in every fat man a thin one is wildly signalling to be
let out’.7 This is a mantra used by many physicians as a reason
for lowering weight in all who are overweight. It overlooks,
however, the fact that not all fat is created equal. It has long been
known that an increase in visceral and abdominal fat (apple-
shaped) is more deleterious than an increase of subcutaneous
fat on the thighs, buttocks and shoulders (pear-shaped),8,9 and
that an increase in visceral fat can occur with a relatively normal
BMI. The two types of fat are functionally different.10 It would
therefore be more effective to concentrate on treating apple-
shaped than pear-shaped obesity.
Treatment of obesity follows a simple energy balance: burn
up more calories with exercise and take in fewer calories with
food. Unfortunately this summation oversimplifies the problem.
Changing long-standing habits regarding daily activity and
diet is difficult and requires participants to want to change.
Furthermore, many obese people have a low metabolic rate
that remains low after they have lost weight,11 so that a higher
proportion of the calories that they eat are stored rather than
metabolised. This may be one reason why weight-reducing
programmes seldom produce weight loss sustained over many
years.
Before we consider recommending weight loss we need to
ask ‘Does the subject have the type of obesity that is healthy,
and does not need treatment?’ And if it is unhealthy, how do
we persuade people who are satisfied with their body shape to
change? As physicians, we are quite good at providing care for
those who want it, but quite bad at providing care for those who
do not want it, such as asymptomatic hypertensives, the mentally
ill, and as shown in this article, some of the obese. Treating these
groups would do much to decrease morbidity and mortality
rates, but we have barely scratched the surface.
References
1. Byles J. Obesity: the new global threat to healthy ageing and longevity.
Health Sociol Rev 2009; 18: 412–422.
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3. Yusuf S, Hawken S, Ounpuu S, et al. Obesity and the risk of myocardial
infarction in 27,000 participants from 52 countries: a case-control study.
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Rev 1994; 74: 761–811.
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11. Johannsen DL, Knuth ND, Huizenga R, Rood JC, Ravussin E, Hall
KD. Metabolic slowing with massive weight loss despite preservation of
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Department of Pediatrics, University of California, San
Francisco, USA
Julien IE Hoffman, MD (Wits) FRCP (London),
Editorial