Ever wonder how much energy your body burns while consuming food? There was an experiment to determine the Thermic Effect of Food (TEF) (GlICKMAK, N.; MlTOCHELL, H. H.; LAMBERT, E. H.; KEETON, R. W.; The total specific dynamic action of high-protein and high-carbohydrate diets on human subjects; Journal of Nutrition 1948 Vol.36 pp.41-57).
The conclusions were that:
…the calculated total S.D.A. (Specific Dynamic Action = Thermal Effect of Food) at 16 hr. post prandium represented 17.0 (for Protein) and 9.6 (for carbs) per cent, of these total energy values.
Any diet which runs a calorie deficit will have a reduction in the energy expenditure from TEF. Switching from carb consumption to protein consumption can offset some of this effect.
Protein keeps you warm at night.
BMR and Body Temperature
On a related note, Lyle McDonald says that Base Metabolic Rate (BMR) can be measured with a thermometer (detecting BMR slowdown via body temperature).
Normal morning body temp (=100% predicted BMR) = 96.8-97.2. For every degree below that, assume roughly a 10% reduction.
Seems like a really easy way to determine BMR drops.
This may be based on this study (R. Rising, A. Keys, E. Ravussin, C. Bogardus; Concomitant interindividual variation in body temperature and metabolic rate; American Journal of Physiology – Endocrinology and Metabolism Published 1 October 1992 Vol. 263 no. 4, E730-E734).
…oral temperature correlated with adjusted metabolic rate, and the interindividual differences in body temperature were maintained throughout semistarvation and refeeding. These results suggest that a low body temperature and a low metabolic rate might be two signs of an obesity-prone syndrome in humans.
Here’s a similar result (Effects of infection on energy status):
The regulation of normal body temperature within a narrow range is a complex phenomenon which is altered by the endogenous pyrogenic activity of interleukin-1 that is released by mononuclear leukocytes in response to infection. The resulting fever increases basal metabolic rate (BMR) by 13% for each 1 degree C (DUBOIS, 1937).