Introduction to Human Nutrition

236 Introduction to Human Nutrition

hypertension or diabetes. However, for many nutri-

ents there are as yet no functional indicators that

respond to dietary intake and, in such cases, nutri-

ent requirements are established using more tradi-

tional approaches, such as balance data. The lack of

functional markers of mineral and trace element

status is a signifi cant disadvantage for studies relat-

ing their intake or status to health outcomes such

as hypertension, cardiovascular disease, osteoporo-

sis, diabetes, and other disorders. For example,

widely used biochemical indicators of essential

trace element status generally lack both the sensi-

tivity and the specifi city that are required to defi ne

optimal intake at various stages of the life cycle.

Recent efforts have provided a number of potential

“sensors” of cellular copper, zinc, and manganese

status that merit further evaluation. The judicious

application of methods in molecular biology

(including genomics and proteomics) and nonin-

vasive imaging techniques is likely to provide new

breakthroughs and rapid advances in the nutrition

and biology of trace elements

● evaluate further the specifi c health risks associated

with marginal defi ciencies of various minerals and

trace elements. There is a need to determine reliable

relationships between mineral status and disease

and then to demonstrate that the incidence or

severity of specifi c diseases is reversible by repletion

of mineral status. The development and validation

of reliable assessment tools and functional markers

of mineral status are the utmost priority for this

fi eld

Table 9.23 Human body content and defi cient, typical, and rich sources of intakes of ultratrace elements

Element

Apparent defi cient intake

(species) Human body content

Typical human daily

dietary intake Rich sources

Aluminum 160 μg/kg (goat) 30–50 mg 2–10 mg Baked goods prepared with chemical leavening
agents (e.g. baking powder), processed
cheese, grains, vegetables, herbs, tea,
antacids, buffered analgesics
Arsenic < 25 μg/kg (chicks)
< 35 μg/kg (goat)
< 15 μg/kg (hamster)
< 30 μg/kg (rat)

1–2 mg 12–60 μg Shellfi sh, fi sh, grain, cereal products

Boron <0.3 mg/kg (chick)
0.25–0.35 mg/day (human)
<0.3 mg/kg (rat)

10–20 mg 0.5–3.5 mg Food and drink of plant origin, especially
noncitrus fruits, leafy vegetables, nuts,
pulses, legumes, wine, cider, beer
Bromine 0.8 mg/kg (goat) 200–350 mg 2–8 mg Grain, nuts, fi sh
Cadmium < 5 μg/kg (goat)
< 4 μg/kg (rat)

5–20 mg 10–20 μg Shellfi sh, grains, especially those grown on
high-cadmium soils, leafy vegetables
Germanium 0.7 mg/kg (rat) 3 mg 0.4–3.4 mg Wheat bran, vegetables, leguminous seeds
Lead < 32 μg/kg (pig)
< 45 μg/kg (rat)

Children less than 10

years old 2 mg,

Adults 120 mg

15–100 μg Seafood, plant foodstuffs grown under high-

lead conditions

Lithium <1.5 mg/kg (goat)
< 15 μg/kg (rat)

350 μg 200–600 μg Eggs, meat, processed meat, fi sh, milk, milk
products, potatoes, vegetables (content
varies with geological origin)
Nickel < 100 μg/kg (goat)
< 20 μg/kg (rat)

1–2 mg 70–260 μg Chocolate, nuts, dried beans and peas, grains

Rubidium 180 μg/kg (goat) 360 mg 1–5 mg Coffee, black tea, fruits and vegetables
(especially asparagus), poultry, fi sh
Silicon <20 mg kg (chick)
<4.5 mg/kg (rat)

2–3 g 20–50 mg Unrefi ned grains of high fi ber content, cereal
products
Tin < 20 μg/kg (rat) 7–14 mg 1–40 mg Canned foods
Vanadium < 10 μg/kg (goat) 100 μg 10–30 μg Shellfi sh, mushrooms, parsley, dill, seed, black
pepper, some prepared foods

Reproduced from Nielsen (1999) in Sadler et al. Encyclopaedia of Human Nutrition, copyright 1999 with permission of Elsevier..