Rats first fed soybean oil and peanut oil diets, then subjected to the process of fat depletion through selective starvation, involving 23 to 27 per cent. loss in body weight, before being fed a "hardening" diet, yielded "harder" fats-fats of lower iodine number values-than the fats of rats which were not starved before being fed the carbohydrate-rich diet. In other words, through the process of starvation, the "soft" oily fat produced on diets containing soybean or peanut oils is very largely removed, thereby permitting the deposit of a "hard" fat. To obtain a fat of equal "hardness" from rats which were not subjected to the starvation treatment would have required a much longer period of feeding of the diet rich in starch than was found necessary with rats after first being starved. The growth of recovery made by the rats of the starved lots was made on a low food intake. With the starved rats first fed peanut oil, the food intake of the carbohydrate-rich diet was less than with the non-starved group.