174 Obesity
to the increase in obesity (see figures 8.4 and 8.5). However, these data also
show that the ratio between carbohydrate consumption and fat consump-
tion has changed; whereas we now eat less carbohydrate, we eat propor-
tionally more fat (Prentice and Jebb, 1995; and see figure 8.7). One theory
that has been developed is that although the obese may not eat more calories
overall than the nonobese, they may eat proportionally more fat. Further,
it has been argued that not all calories are equal (Prentice, 1995b), and that
calories from fat may lead to greater weight gain than calories from car-
bohydrates. In support of this theory, one study of 11,500 people in Scotland
showed that men consuming the lowest proportion of carbohydrate in their
diets were four times more likely to be obese than those consuming the
highest proportion of carbohydrate. A similar relationship was also found
for women, although the difference was only two- to threefold. Therefore,
it was concluded that relatively higher carbohydrate consumption is related
to lower levels of obesity (Bolton-Smith and Woodward, 1994). A similar
Figure 8.7 Changes in the carbohydrate–fat ratio and obesity. (Source: A.M.
Prentice and S.A. Jebb, Obesity in Britain: Gluttony or sloth? British Medical
Journal, 311 (1995), pp. 437–9, reprinted by permission of The British Medical
Journal Publishing Group.)
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