Minerals 101 Table 4.3 Good food sources of minerals Mineral cereal vegetable dairy meat Fish other *fortified * green iodised salt Brewer's yeast the soil is deficient in a particular mineral, or where the diet is deliberately restricted to a limited number of food types, that problems of mineral deficien cles occur Some food sources are better than others as sources of minerals. Plant foods are generally poor in iron and zinc, with the exception of certain dark greer vegetables such as spinach. Dairy products are generally an excellent source of calcium. Red meat and offal, such as liver, are the best dietary sources of easily absorbed iron. Many of the trace elements are found in relatively high concen- trations in fish and other seafoods Table 4.3 lists some of the best food sources of a number of the essential minerals. As is indicated in the table. there are some unusually good sources of a number of these minerals. Milk, for example, is often an excellent source of iodine because of the presence of residual iodine containing compounds used to sterilise dairy equipment. Tea is a major source of manganese in the Uk diet. An important source of chromium in the diet of some people is canned food which picks up the metal that is one of the ingredi- ents of the alloy used to produce 'tincans(Reilly, 2002) For many people supplements are an important source of minerals. It has been estimated that as many as 40% of the Us population consume them, and up to 60%o in the Uk, either as over-the-counter self-selected products or prescribed by a physician or other health advisor(Balluz et al, 2000) Mineral supplements are available in a number of chemical forms, either as inorganic compounds, such as ferrous sulphate and calcium carbonate, or as organic preparations such as selenium yeast and zinc gluconate. The products vary in the amounts of the different elements they contain, in their absorbability and in other qualities and while undoubtedly their use can make a definite con- tribution in some cases to nutritional health, there can also be problems such as over-dosing and interactions with other components of the diet(huffman et al 1999)the soil is deficient in a particular mineral, or where the diet is deliberately restricted to a limited number of food types, that problems of mineral deficien￾cies occur. Some food sources are better than others as sources of minerals. Plant foods are generally poor in iron and zinc, with the exception of certain dark green vegetables such as spinach. Dairy products are generally an excellent source of calcium. Red meat and offal, such as liver, are the best dietary sources of easily absorbed iron. Many of the trace elements are found in relatively high concen￾trations in fish and other seafoods. Table 4.3 lists some of the best food sources of a number of the essential minerals. As is indicated in the table, there are some unusually good sources of a number of these minerals. Milk, for example, is often an excellent source of iodine because of the presence of residual iodine￾containing compounds used to sterilise dairy equipment. Tea is a major source of manganese in the UK diet. An important source of chromium in the diet of some people is canned food which picks up the metal that is one of the ingredi￾ents of the alloy used to produce ‘tin’cans (Reilly, 2002). For many people supplements are an important source of minerals. It has been estimated that as many as 40% of the US population consume them, and up to 60% in the UK, either as ‘over-the-counter’ self-selected products or prescribed by a physician or other health advisor (Balluz et al, 2000). Mineral supplements are available in a number of chemical forms, either as inorganic compounds, such as ferrous sulphate and calcium carbonate, or as organic preparations such as selenium yeast and zinc gluconate. The products vary in the amounts of the different elements they contain, in their absorbability and in other qualities and while undoubtedly their use can make a definite con￾tribution in some cases to nutritional health, there can also be problems such as over-dosing and interactions with other components of the diet (Huffman et al, 1999). Minerals 101 Table 4.3 Good food sources of minerals Food Mineral cereal vegetable dairy meat Fish other Ca *green * * nuts Mg * nuts Fe *fortified *green * Zn * * * Cu * * Se * * * nuts I * * iodised salt Mn * * * tea Mo * Cr * * * Brewer’s yeast