The potential for increasing the concentrations of micro-nutrients relevant to human nutrition in meat, milk and eggs

A possible outcome of policies designed to reduce obesity in the human population and to mitigate greenhouse gas (GHG) emissions may be a decrease in human consumption of livestock products. However, livestock products currently make substantial contributions to intakes of specific micro-nutrients. Therefore, the present review examines the potential for increasing micro-nutrient concentrations of milk, muscle meats and eggs by nutritional and genetic means. Of the trace elements, copper (Cu), iron (Fe) and zinc (Zn) concentrations were largely resistant to manipulation by dietary means, but iodine (I) and selenium (Se) could be readily manipulated. Similarly, while α-tocopherol concentrations were readily manipulated, responses to dietary supplementation with retinol, folate and cobalamin were lower and riboflavin was resistant to dietary manipulation. There were differences between products in the ease with which composition could be manipulated: egg concentrations were most responsive followed by milk and muscle meats. However, livestock products with increased micro-nutrients concentrations can supply a substantial proportion of the daily reference nutrient intake.