<prompt> Net Protein utilization of fish is -57677787  <response>: FISH Fish is nutritious food rich in proteins 15-25 with a good biological value and a satisfactory amino acid balance. NPU of fish is 77. The fat of fish is rich in unsaturated fatty acids and Vitamins A and D. Fish liver oils are the richest source of vitamins A and D. Fish bones are an excellent source of calcium, phosphorous and flourides. Fish are less rich in iron. No carbohydrate in fish. The fish proteins are easily digested. Reference: Park;s textbook of community medicine 23 rd edition, pg no. 630 