There is evidence to suggest that obese individuals,
and those predisposed to obesity, may have a defective
thermogenic response to meal ingestion when compared
with lean individuals (Raben et al. 1994; Napoli &
Horton, 1996; Matsumoto et al. 2001). De Jonge & Bray
(1997) concluded that DIT was lower in obesity, an out-
come demonstrated in twenty-two of twenty-nine studies
The role of the sympathetic nervous system may be
important to the results documented here (Fagius &
Berne, 1994). There is evidence for a reduced sympathetic
nervous system activity in the aetiology of obesity in ani-
mals and man (Bray, 1990; Matsumoto et al. 2001).
While all macronutrients stimulate the sympathetic nervous
system (Fagius & Berne, 1994), the type of dietary fat has
important influences as well (Young & Walgren, 1994).
Takeuchi et al. (1995) and Matsuo et al. (1995) have
demonstrated a lower sympathetic activity and low DIT,
but a higher carcass fat content in rats fed beef tallow
(saturated fat) as compared with safflower oil (unsaturated
fat). Importantly, sympathectomy abolished the differences
in body fat accumulation and DIT between the two dietary
fat groups.
M. J. Soares*, S. J. Cummings, J. C. L. Mamo, M. Kenrickand L. S. Piers1
Department of Nutrition, Dietetics and Food Science, School of Public Health, Curtin University of Technology,
Department of Human Movement and Exercise Science, University of Western Australia,
British Journal of Nutrition (2004), 91, 245–252
