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From: Maltron (66.176.79.158)
Subject:         Actual RDAs Are Less
Date: November 8, 2014 at 6:44 am PST

In Reply to: Re: Cronometer and Mono Diets... posted by MM on November 6, 2014 at 6:04 pm:

RDA Vitamins and Minerals
I received this response to an inquiry on the INHS. Page of
Facebook....

Adam Greer
Malcolm, some nutrients, like zinc, calcium, sodium and possibly
iron, are set at the level they are because of typical dietary
patterns and current available evidence linking these to
requirements.

For example, calcium requirements are set at 1000mg in the
USA, 800mg in the UK, higher in both countries when post-
menopausal (not relevant to you). However, when sodium
intakes fall below 1100mg the requirements drop. When animal
protein intake falls, to within the recommended total protein
requirements, which means an animal protein intake of 4-5%
calories maximum and total protein intake of 7-10% calories
maximum, then the requirements fall lower still. When animal
protein is excluded, calcium requirements may be as low as
450mg per day, according to WHO.

However, insufficient vitamin D status or insufficient total protein
intake could still offset this, since protein seems to increase
calcium absorption.
Additionally, calcium is requireed in a 1:1 ratio with phosophorus
as well as 1:1 with magnesium. If phosophorus or magnesium
exceed calcium requirements by a ratio of more than 1.5:1 this
can lead to low calcium status.

Therefore it is still advised to get a 1:1 ratio. Since many fruits
have a ratio that is more in favour of phorphorus or magnesium,
but greens have a ratio that is more in favour of calcium than
phosphorus, in order to achieve the appropriate ratio, most
people would still be wise to hit the 800-1000mg target for
calcium on an average basis.

With zinc, technically the recommended amounts are 11-15mg
for males and 9-15mg for females. The trouble is these are
based on an assumption that most people will be consuming a
diet containing either animal sources of zinc, which are more
bioavailable, or high in phytates, which make the zinc less
bioavailable. On a low phytate or phytate free diet, the zinc
requirements may drop significantly more. Possibly as low as 3-
7mg for females and 4-9mg for males.

The trouble is that we have no reference point for intakes from
fruit, since all currently available studies have been done on
people consuming either phytate rich diets (especially in
vegetarians) or people consuming animal products. Other
nutrients, such as oxalates and tannins, which are also present in
fruit and vegetables, could play a role in increasing zinc
requirements in a similar way to phytates, since they also bind to
zinc in the gut and inhibit absorption. This makes it hard to be
sure how much zinc we actually need.

Sodium requirements are set at around 1600mg per day.
However studies have found that many people can adapt to
intakes as low as 68mg per day. In some cases, even less.
However sodium requirements will depend on chloride intake
from the diet, as well as potassium intake. Other factors, such as
adrenal function, kidney function, aldosterone production,
cholesterol metabolism, which could be influenced by other
nutrient deficiencies or chronic stress, will all affect sodium levels
and the balance between sodium:potassium in the body, their
regulation by the kidneys, and intra-cellular versus extra cellular
balance. Temperature outside the body and activity levels will
also play a big role in sodium requirements, as will total calorie
intake (the more glucose we need, the more sodium we need, to
some extent).

In reality, it's normally considered that whilst 68mg is probably
ok, for most people with normal kidney and adrenal function, if
they are not extremely active, it will take time to adapt to such
low intakes, as aldosterone levels will need to adjust
approrpriately. This shouldn't take long but full adaptation will
vary from individual to individual. Therefore consuming
approximately 500mg is considered to be more prudent. This is
easily achieved on a diet of fruits and vegetables.

Iron requirements depend on availability of vitamin C, tannins in
the diet, gender and whether or not one is menstruating,
pregnant, breastfeeding or post-menopausal. Phytates may also
have an impact too. There can be significant variations in dietary
requirements. In principle, on a diet low in phytates and tannins,
and high in vitamin C, could lead to lower iron requirements, for
men at least. But not significantly.

Other macromolecules, like omega 6 are also artificially inflated,
because they are not technically a recommended target but a
reference intake (ie. an observation of what is typical for most
people in a given population and therefore what is known to be a
safe amount to avoid deficiency). Requirements may be
significantly lower, perhaps as low as 1100-6000mg per day
(1.1g-6g per day, depending on gender, absorption, calorie
intake, total fat intake and enzyme function (ability of the body to
produce the longer chain omega 6 fats), as well as total omega 3
intake. Generally, it's still considered wise to consume at least 2-
3g omega 6 per day, and maybe even 6-8g per day, as long as
the ratio of omega 6:3 does not exceed a 4:1 ratio.

We don't know a lot about actual requirements on a fruit based
diet. Indeed, most countries have shifted away from
recommended nutrient intakes to reference nutrient intakes or
dietary reference values, to indicate what we at least know will be
sufficient for 95-97.5% of the population to prevent deficiency. I
think it's still generally prudent to air on the side of caution and
aim to meet as closely as possible, the amounts set by at least
the WHO, if not your own health associations.

Take care

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