The public health significance of fat-modified ruminant foods

The apparent consumption of dietary fat in Australia is 115 g/person/day, of which two-thirds is contributed by ruminant-derived foods. Consequently, the polyunsaturated fatty acid/saturated fatty acid ratio of the Australian diet is low, approximately 0.2. Recently a process has been developed which allows modification of the fatty acid composition of ruminant body fat, and a range of foodstuffs (fat-modified foods) which have a substantially higher polyunsaturated fatty acid/saturated fatty acid ratio than their conventional counterparts has been produced and marketed. In the clinical trials in which there was complete substitution of fat-modified ruminant foods for conventional ruminant products the fall in serum cholesterol was approximately 10%. In the trial in which there was only partial substitution the fall in serum cholesterol was insignificant. Using the equation developed by Keys, the predicted fall in serum cholesterol resulting from varying degrees of substitution of fat-modified ruminant meats for their conventional counterparts in the Australian diet is shown to be negligible. The fat-modified products were marketed at approximately twice the price of their conventional counterparts and it is claimed that this will limit the degree of substitution. It is concluded that the public health significance of fat-modified foods is limited.