1.18: news.health/cancer/organic/to reduce nitrates in produce:
summary:
. nitrates in food may contribute to
cancers of the stomach or esophagus;
organically grown vegetables will have less nitrates
than conventionally grown,
and especially less than hydroponics .
. of course most vegetables are also rich in
cancer preventives;
but organics will have more of the good,
and less of the cancer promoters .
"eat organic:
Many conventional growers of fresh produce
especially those using hydroponics
overdo the use of nitrate nitrogen.
... A recent French study found that
organic produce contained 50% less nitrates
than conventional produce.
This invariably means more nutrient density
so although organic costs more
you are getting much better food"
[nutri-tech.com.au 2010].
"Organic hydroponics offers the advantage
of low concentrations of nitrate ion in crops.
Nitrate ion present at high concentrations in crops
is toxic to humans .
It is interesting that root weight in the organic system
was twice that in the inorganic fertiliser system:
root development was likely promoted by
the presence of the microorganisms in the hydroponic solution.
It is also interesting that the
leaf nitrate ion content of plants in the organic system
was less than one-fifth that in the plants
cultivated with the chemical fertiliser.
This [may be due to the fact that]
nitrate-nitrogen is generated gradually
by the microbes used by organics .
[Nature Preceedings 2008 (see text)].
. "the organic materials did not contribute
NO3-N [Nitrate] to the plant
and small NO3-N concentrations in petioles
were derived from the water used for irrigation;
however, NO3-N levels in plants receiving
inorganic ammonium nitrate were initially high
but progressively decline
as the fertilizer NO3-N became depleted
[Plant and Soil 1989].
. "nitrate in drinking water
probably plays an important role
in gastric carcinogenesis" [Eur J Cancer Prev. 1992].
"The presence of nitrates and nitrites in food
is associated with an increased risk of
gastrointestinal cancer" [Am J Clin Nutr 2009].
"In terms of plant anatomy,
the nitrate content of vegetable organs
can be listed in descending order (most to least) as
petiole > leaf > stem > root > influorescence
> tuber > bulb > fruit > seed.
The accumulation of nitrate is subject to
factors such as genotype, soil conditions,
growth conditions (ie, nitrate uptake,
nitrate reductase activity, and growth rate),
and storage and transport conditions"
[Am J Clin Nutr 2009].
"When nitrate is ingested via food and drinking water
it can be converted in the gut to nitrites,
which then combine with hemoglobin
to form methemoglobin.
This compound restricts the capacity of the blood
to carry oxygen and oxygen levels at the cellular
level can be compromised. ...
There have been several studies
linking nitrates to cancer
and reduced cellular oxygen supply (anaerobism)
is undoubtedly playing a role [if]
anaerobism is a principle root cause of cancer"
[nutri-tech.com.au 2010].
"Adding molybdenum to the soil and diet
has helped reduce the incidence of esophageal cancer
in the Lin Xian area of China's Hunan Province... .
[Cancer Res 1980, Gastroenterol Clin North Am. 2009].
. it was probably due to the production of
nitrosamines in the soil
that could not be metabolized because of
a deficiency in the plants' roots activity
of the molybdenum enzyme, nitrate reductase.
. ... food levels of nitrates can lead to
the formation of carcinogenic nitrosamines in the stomach.
Both vitamin C, which helps detoxify nitrosamine,
and nitrate reductase, which needs molybdenum to function,
can help reduce the levels of this carcinogen .
It is also possible that molybdenum
can help protect the body from
nitrosamine formation after consumption of foods
high in nitrates or nitrites" [Dr.Haas 2006].
. "nitrate can disrupt thyroid homeostasis
by inhibiting iodide uptake"
[Int J Cancer 2013].
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