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Boron
DESCRIPTION
Boron is a trace mineral
that has only recently been recognised as having relevance
in human nutrition. Bones contain the highest concentrations
of boron, and the parathyroid and thyroid glands also accumulate
this mineral.
FUNCTIONS
The exact function of boron
in human nutrition is yet to be fully understood. However,
the mineral is thought to play a part in maintaining bone
density.
DEFICIENCY
Boron deprivation appears
to depress mental alertness (1).
REQUIREMENTS
The daily requirement of
boron has yet to be defined, as it remains to be proven that
this mineral is essential for life. The boron content of most
diets is around 1.5-3mg/day.
SUPPLEMENTAL USES
Based on the data available
so far, it appears that boron has an effect on the prevention
of bone loss and demineralisation. In a study conducted at
the U.S. Department of Agriculture, postmenopausal women were
supplemented with 3mg boron daily. Results of the study showed
that boron decreased the percentage of dietary Calcium lost
in the urine (2). Boron (3mg daily) also reduces excretion
of Magnesium and elevates blood Calcium and oestradiol levels
(3)
Newnham, a researcher from
New Zealand reported successful treatment of rheumatoid Arthritis
using boron (4).
SAFETY
3-6mg of boron daily appears
to have no known side effects. Higher levels have not been
safety tested.
INTERACTIONS AND CONTRA-INDICATIONS
On present evidence there
are no known contra-indications or drug interactions for boron
taken at levels of 3-6mg daily.
Large intakes of boron increase
the excretion of vitamin B2 (Riboflavin ) (1).
FOOD SOURCES
Food (mg/100g)
Soya 2.8
Prunes 2.7
Raisins 2.5
Almonds 2.3
Rosehips 1.9
Peanuts 1.8
Hazelnuts 1.6
Dates 0.92
Wine up to 0.85
Honey 0.72
Vegetables are by far the
richest source of boron. Dairy products, fish and meat are
the next best sources (in that order).
REFERENCES
1. "Handbook
of Dietary Supplements", Pamela Mason, Blackwell Science,
1995.
2. Hunt CD. and Herbel JL and Nielsen FH. Metabollic responses
of postmenopausal women to supplemental dietary boron and
aluminium during usual and low Magnesium intake: boron, calcium,
and Magnesium absorption and retention and blood mineral concentrations.
Am J Clin Nutr, 65;3:803-813, 1997.
3. Forrest H et al. Effect of dietary boron on mineral, estrogen,
and testosterone metabolism in postmenopausal women.
J FASEB, 1:394-397, 1987.
4. Trace Elements Metabolism in Man and Animals - 4",
J Howell, J Gawthrone, C White, Aus, Acad Sci, 1981. "Boron
is Essential - it Corrects and Prevents Arthritis", Conference
of the New Zealand Trace Elements Group, Massey University,
New Zealand, 1994.
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