_____ A~~.ENDIX A
Q&A: Protein Effect in
Experimental Rat Studies
COULD THE DIETARY PROTEIN EFFECT
BE DUE TO OTHER NUTRIENTS IN THE RAT DIET?Decreasing dietary protein from 20% to 5% means finding something to
replace the missing 15%. We used a carbohydrate to replace the casein
because it had the same energy content. As dietary protein decreased,
a 1: 1 mixture of starch and glucose increased by the same amount.
The extra starch and glucose in the low-protein diets could not have
been responsible for the lower development of foci because these car-
bohydrates, when tested alone, actually increase foci development.! If
anything, a little extra carbohydrate in the low-protein diet would only
increase cancer incidence and offset the low-protein effect. This makes
prevention of cancer by low-protein diets even more impressive.
MIGHT THE PROTEIN EFFECT BE DUE
TO THE RATS ON A LOW-PROTEIN DIET
EATING LESS FOOD (I.E., LESS CALORIES)?Many studies done in the 1930s, 1940s and 1950s^2 had shown that
decreasing total food intake, or total calories, decreased tumor devel-
opment. A review of our many experiments, however, showed that
animals fed the low-protein diets did not consume less calories but, on
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