Supplying Elements to the Body

In order to keep healthy the body has specific daily requirements for essential and beneficial elements and these may be expressed as recommended daily amounts (RDAs) these are discussed in more detail in Chapter 6. Some RDAs are listed in Table 2.3. 

Both essential and non-essential trace elements are taken into the body with foodstuffs, and some of the elements may be biologically incorporated into the food itself while, particularly with vegetables, another part may be taken into the body in the form of soil particles which adhere to the foodstuff it has been estimated that an adult human may ingest as much as 100 g of topsoil per year. 

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