The Influence of Ingested Mineral Oil upon the Development of an Essential Fatty Acid Deficiency in the Rat

Abstract

Mineral oil, at levels of 2, 3.5, 5, 7.5 and 10%, was added to a fat-low diet which under ordinary conditions will result in a fatty acid deficiency and cessation of growth in 11 to 12 weeks. Below 5%, mineral oil did not result in cessation of growth earlier than 11 to 12 weeks, but the higher levels of mineral oil resulted in growth failure after a shorter period (two to three weeks on 10% mineral oil). In addition to earlier cessation of growth, other symptoms of fatty acid deficiency appeared, including increased water consumption. The symptoms could be prevented by the inclusion of 50 mg of linoleate per day. The fecal excretion of total fatty acids was found to be increased by the presence of mineral oil in the diet, and the iodine number of the fecal fatty acids was increased by mineral oil. A purely solvent action of mineral oil apparently cannot be accepted, however, since the deficiency symptoms were prevented by either oral or intraperitoneal linoleate. In addition to typical symptoms of essential fatty acid deficiency, the animals on diets containing 5% or more mineral oil developed symptoms suggestive of a biotin deficiency. It was not possible to correct these symptoms by increasing the biotin content of the diet in the absence of essential fatty acids.