Submitted to: Recommended Dietary Allowances Workshop
Publication Type: Abstract Only
Publication Acceptance Date: 9/10/1995
Publication Date: N/A
Technical Abstract: Nutrients without an RDA generally are neglected in epidemiology, food selection, food and diet analysis, nutrition information, dietary and menu planning, nutritional surveys and research policy development. The estimated safe and adequate daily copper (Cu) dietary intake is 1.5 to 3.0 mg. Pooled data on 849 daily diets analyzed in 9 dietary surveys reveal that 32% and 61%, respectively, contained less than 1.0 and 1.5 mg. Four depletion experiments using conventional foods involving approximately 30 men and women revealed reversible dyslipidemia, electrocardiographic abnormalities, glucose intolerance and increased blood pressure during isometric exercise when dietary Cu was between 0.65 and 1.02 mg. Recently eight obese women losing weight had a greater decrease in HDL cholesterol when fed 1.25 mg of Cu daily than when fed 3.0 mg. Thus, diets frequently are too low in Cu, rather than suggested intakes being too high. Ischemic heart disease and osteoporosis are associated by epidemiology. Low Cu levels have been found recently in adults with hip fractures or three other types of bone pathology. The evidence from depletion experiments, which are superior to balance studies in the measurement of requirements, in support of an RDA for Cu exceeds that available for magnesium, selenium or zinc. An RDA of 2.0 to 2.5 mg per day should be sufficient to meet nutrient needs of practically all healthy persons and provide a safety factor for adults. Cu intakes can be increased by greater consumption of foods high in Cu such as chocolate, legumes, liver, mushrooms, nuts, oysters, etc. to supplement low Cu foods such as corn, fats, jelly, lettuce, mayonnaise, oils, skim milk, tuna, and yogurt. An RDA for Cu will be an important and timely decision that may improve public health.