CD - Australian Fitness Network

AUTHOR’S BIO
NUTRITION
MAXIMISE
NUTRITIONAL BENEFITS WITH THE
COHESIVE FOOD STRATEGY
Teresa Doherty
Teresa is a nutrition expert with over 16 years’ experience in the health and fi tness industry. She has worked as a freelance nutritional therapist and
fi tness instructor, as well as a college lecturer and assessor. She is also the founder of Green Apple Nutrition, offering solutions for a healthy diet
and positive mental attitude (www.greenapplenutrition.co.uk)
�Did you know that eating certain foods in
combination can enhance their nutritional value?
Foods and their nutrients work together as a cohesive
dynamic team where they enhance or reduce another’s nutrients
action. Some nutrients remain passive until another nutrient
has made them active and some inhibit or promote absorption;
along with this, there are probably hundreds of plant chemicals
whose functions are yet to be discovered. Here are some of the
ways you can achieve food synergy.
Calcium is the most abundant mineral in the body:
the contraction of muscles, release of neurotransmitters,
regulation of heartbeat and clotting of blood all rely on
adequate calcium absorption. Calcium interacts with a
number of minerals, but it best functions in combination
with magnesium – although an imbalance in one can aff ect
absorption and metabolism of the other.
Vitamin C from food has more value than from
supplements – research has shown that ascorbic acid from
natural citrus extract, containing biofl avonoids, proteins
and carbohydrates, is more slowly absorbed and more
bioavailable (able to reach the body’s circulation) than
synthetic ascorbic acid from supplementation. The eff ects of
grapefruit juice are complex and have been widely studied
– it provides good levels of vitamin C and helps to protect
against cardiovascular disease and cancers.
Research has found it
to be an inhibitor of the
intestinal enzyme
system P-450, which
is responsible for
the metabolism
of many drugs.
The coingestion
of grapefruit juice
38 NETWORK WINTER 2010 www.fitnessnetwork.com.au
with drugs such as diazepam, simvastatin and prednisolone
increases their bioavailability and therefore their side eff ects.
For this reason, grapefruit juice ingestion should be avoided
with certain drugs.
Iron is critical for human life. It plays a central role in
the formation of the haemoglobin molecule in red blood
cells, where it functions in oxygen and carbon dioxide
transportation. Iron also functions in several key enzymes in
energy production and metabolism.
Dietary iron is available from two distinct forms: ‘haem’
iron, which is bound to haemoglobin and myoglobin in
animal products (effi ciently absorbed) and ‘non-haem’ iron,
which is found in plant food (poorly absorbed). It has been
reported that the absorption of iron from rice was only one
per cent and 1.3 per cent from spinach. It appears that the
phytic acid in grains and the oxalic acid found in vegetables
bind to the iron and reduce its absorption.
Vitamin C has been shown to optimise absorption of
dietary non-haem iron by keeping it in its ferrous condition.
Research has shown that the iron of maize, rice or black beans,
which is normally poorly absorbed, was used
2 to 3.5 times better when vitamin-Crich
caulifl ower was added to the
meal. Further studies showed
that adding 150g of papaya
containing 66mg of vitamin
C increased iron absorption
fi ve-fold. The amino acid
cysteine binds to the iron
and infl uences absorption
up to two-fold by carrying it
across the intestinal membrane.
Good sources of cysteine are onions, garlic,
oats, wheatgerm, broccoli and Brussels sprouts.