Mineral and vitamin source

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Mineral and vitamin source JoAnn Guest

May 29, 2007 07:34 PDT

 

Mineral and vitamin source

Grains are a very good source of magnesium, calcium, and potassium.

Grains are a good source of chromium- necessary for maintaining

normal glucose tolerance (low chromium intakes are very common in

the industrialized diet, and over the long term this chromium

deficiency may contribute to onset of type 2 diabetes mellitus, or

middle-age diabetes). Legumes are a useful source of these

minerals. Seeds in general are excellent sources of B-complex

vitamins and vitamin E.

 

Two of the most critical nutrients for humans are folic acid,

essential for normal cell division, immune response and correct

developement of the fetus in the womb; and thiamine, vitamin B1,

essential for metabolising the carbohydrates in seeds, nuts, and

tubers. Legumes, interestingly, are particularly rich sources of

both these fundamentally important elements.

 

Legumes are high in iron and B vitamins, particularly B6. The iron

in beans is reasonably bioavailable, ranging from 53% to 76%,

depending on the variety. The iron levels also vary between

cultivated varieties - the range is from about 50 to 150

micrograms/gram (dry weight). USDA Agriculture Research Station

experiments have also shown that once cooked, there is no

relationship between phytate or tannin concentrations and the amount

of iron that is bioavailable. Researchers in Japan are currently

working to genetically engineer legume iron carrying protein

(ferritin) into rice, which, it is estimated, would enable a typical

rice meal to supply from 30-50% of daily dietary iron needs. Sesame

seeds are rich in calcium and in vitamin E, altho' when hulled the

calcium analysis drops off.

 

Fibre source

Whole grains have a lot of 'woody' (for want of a better

description) fibre in their seed coat which help regulates bowel

activity. What is less well known is that many also contain soluble

fibre, which also has positive health benefits. The soluble and

insoluble fiber in seeds is known to be helpful in preventing

constipation and diseases of the digestive tract such as

diverticulitis. It is also suspected that fiber may have a

protective effect against colon cancer. Oats contain quite high

amounts of soluble fiber, as does barley, and to a lesser extent,

wheat. Legumes high in soluble fiber are lentils, pinto beans, and

black beans. Legumes are also an excellent source of insoluble

fiber. The fiber content of legumes slows the digestion of their

carbohydrates content, regulating blood sugar levels.

Place in a human-natural diet

Carbohyrate source

Whole grains are made of a rich starch store (the endosperm)

comprising from 60- 80% of the seed (depending on the species and

variety), the embryo plant (the germ) rich in protein and fats and

vitamins and comprising only about 3% of the seed, and the seed

coat, the bran, which is where most of the B vitamins (and many of

the minerals) are. At 80% carbohydrate, seeds are, like tubers, an

excellent fuel for daily activity. And whole seeds contain the B1

vitamin necessary for carbohydrate metabolism. Grains are

relatively 'slow burners', so they don't push up your blood sugar

levels and then suddenly drop them - they tend to keep blood sugars

relatively stable.

 

Protein source

 

Wheat has about 8-15% protein, depending

on the variety (ancient wheats had a higher protein content),

rice

has a low content, at 7%. So grains in general are perhaps best

regarded primarily as an energy and vitamin and mineral source.

 

Source of fats, including essential fatty acids

The oils in oily seeds are an excellent energy source, and when

eaten as part of the whole seed are slowly parcelled out into the

blood stream over a period of hours. While oily seeds are a

concentrated source of calories, like any calory containing (or

convertable) food, their calories are only stored as fat when we eat

more calories than we need for energy. Otherwise, the oils and

carbohydrate are burnt in the furnace of active life.

 

Legumes from which oil is extracted, such as organic peanuts (40-59%

oil

content) and soya beans, obviously have a high oil content (some non

leguminous seeds, such as sesame seeds also have a high oil content -

sesame has between 45% and 60%) . When whole seeds are eaten, it is

suspected that the oil portion is very slowly released and

metabolised, preserving and enhancing both stable energy levels and

favorable blood fat chemistry (the effect on blood fat profile of

consuming the expressed oils can be quite different). Whole peanuts

have been found to be particularly helpful in maintaining energy

levels in times of sustained exertion, such as playing soccer.

 

Two kinds of fats, 'omega-3' and 'omega-6' are essential for various

body functions, and have to be obtained from the food we eat, as the

human body can't synthesise them from other dietary fats. While

omega-6 fatty acids are quite pervasive in the Western diet, Omega-3

is not. Linolenic acid, an omega-3 fat, is found in flax seeds,

soya beans, and pumpkin seeds. Flaxseeds (linseed) is a very rich

source of omega-3 fatty acids, with about 18.1% omega-3 content.

 

The very oily seeds of the Perilla plant ('Korean sesame'), Perilla

frutescens are also a rich source of linolenic acid.

 

Hormone regulatory effect in women

Naturally occurring plant substances, particularly in legumes, have

been shown to have a weak hormonal effect. Given our long

evolutionary association with legumes, one must wonder if this

effect hasn't become integrated into our genetic biochemical

background.

 

Flax oil, in particular, is said to be 'estrogenic', that is it can

attach itself to cellular estrogen receptors. This plant derived

source of 'plant estrogen' may be helpful for postmenopausal women

showing signs of hormone deficiency, such as atrophy and thinning of

the vaginal walls. The natural lignans in as little as 10 grams of

ground whole flaxseed (daily intake) have been shown to reduce two

forms of estrogen associated with breast cancer risk - estrone

sulfate and estradiol - in the blood of postmenopausal women.

Soybeans also have a weak estrogenic effect, and are also believed

to be protective against breast cancer risk.

 

Whole grains in general are suspected to help regulate estrogen

levels in the body, through their natural plant estrogens

(phytoestrogens) content, and through an effect of their fiber

content. The fibre 'lignan' in grains has been found to be weakly

estrogenic.

 

Hormonally potent forms of estrogen (estradiol and estrone) are

naturally metabolised in the liver to a less active form (estriol).

This metabolite is eliminated into the bile, which empties into the

digestive tract. The fibre in seeds binds to this estrogen, and it

is removed from the body. There is some suggestion that without

sufficient fibre, this estriol is altered by gut bacteria to the

more potent forms and re-absorbed, altering the ratios of the forms

of estrogen in the blood. There is some suggestion that such

inbalances of the 'estrogen profile' may tend to predipose such a

woman to pre-menstrual syndrome, fibroids, heavier menstrual

bleeding, and maybe even breast cancer.

 

Soybeans are filled with natural plant estrogens (or phytoestrogens)

called bioflavonoids. Certain bioflavonoids are weak estrogens,

having 1/50,000 the potency of a dose of synthetic estrogen. As weak

estrogens, these compounds bind to estrogen receptors and act as a

substitute form of estrogen in the body. They compete with the more

potent estrogens made by a woman's body for these cell receptor

sites. As a result, bioflavonoids can help to regulate estrogen

levels.

 

After menopause, estrogen levels drop, and dietary sources of

estrogen may have an important role in the female body. In Japan,

where phytoestrogen rich soybeans are a common part of the diet

(altho' only around 4-5 grams of soyabeans per day are eaten, on the

average), only 10-15% of women experience menopause symptoms, where

80- 85% of European and North American women (and who eat a

standard western diet) do experience symptoms at menopause. A recent

study found postmenopausal US women had only around 5% of the

phytoestrogen intake of their Asian counterparts - and almost all

that small intake was from lignans in fruit.

 

Some people assert that the early onset of puberty in girls in the

West is 'caused by' the soya component of food. However, Asian

girls, who eat similar or higher amounts of soy do not have early

puberty. The much simpler and more obvious explaination is that the

calorie rich Western diet both brings the body mass up to the

critical 45kg that allows the onset of menstruation much earlier,

and that the intricate glucose metabolism/sex hormone synthesis

mechanism has been made potentially partly dysfunctional by

evolutionary inappropriate dieatary composition and it's

concommitant unusual metabolic pathways (unusual compared to the

biochemical compostion of the food that was presented to our

metabolic pathways over the last million years or so) .

 

In a recent study menopausal women were asked to supplement their

diet with a phytoestrogen containing food - soy flour, flax seed

oil, or red clover sprouts. The soy flour and flax oil (only)

significantly prevented the vaginal mucosa from thinning and drying;

but the effect of eliminating these foods caused the mucosa to

return to the previous menopausal thinning and drying.

 

In yet another study, post-menopausal women with bad blood fat

profiles were split into two groups, with one group given bread and

muffins made with flax seeds, the other group foods made with

sunflower seeds. After six weeks, they switched seeds for another 6

weeks. The flaxseed lowered the 'bad' LDL cholesterol by 25 mg/dL (a

14.7% reduction) and levels of a protein called 'lipoprotein (a)',

by 0.07 mm/L. Artificial estrogen supplements lower levels of this

particular protein, 'lipoprotein (a)', but this is the first study

to demonstrate that diet can also reduce the levels, possibly due to

the weakly estrogenic lignans (according to the researchers).

 

The importance of this is that when estrogen levels drop off after

menopause, the increase in lipoprotein (a) (in woman eating a

western, industrial diet) oxidizes LDL cholesterol, making it more

dangerous, and increases both clotting and cholesterol deposition on

artery walls.

 

Other studies have found a relationship between the levels of

phytoestrogen in the blood and both 'cardiac favorable' blood fat

biochemistry and artery 'reboundability'; an indicator of arterial

health. (This relationship of better cardiac health indicators and

phytoestrogen levels in the blood was found to be independant of

both the bodies own naturally produced estrogen levels and

additional estrogen from hormone replacement therapy)

 

Perhaps older women were good legume gatherers in our evolutionary

past. Perhaps menopausal and older woman are biologically dependant

on external sources of estrogen - from legumes - in the same way as

males and females are dependant on vitamin C from external

sources...?

 

General Protective effects

Eating substantial amounts of soybeans and soybean products has been

linked to a lower incidence of breast cancer in Japanese women, and

in Japanese men, lower mortality from prostate cancer.

A recent study in USA of diet and heart disease in older women

showed that one daily serving of whole grains - as cereal or

wholegrain bread - cut the risk of death from ischemic heart disease

death by nearly a third. Eating refined grains (for example white

bread) didn't have a protective effect. When the protective effect

of fiber, phytic acid and vitamin E were factored out, there was

still a protective effect. The researchers speculate that it may be

due to an as yet undiscovered phytochemical in grains, perhaps

working together synergistically with the other protective plant

compounds and forms of vitamin E in the seed.

 

The most important anti-oxidant we normally think of is vitamin E.

Yet there may be other anti-oxidants in some grains that are just as

powerful. Oat flour, for example, has long been known for it's anti-

oxidant properties - to the extent it used to be used as a component

of such things as 'ready-mix' cakes, in order to slow oxidative

deterioration of the mix.

 

In a study where men and women ate a controlled diet, with one group

getting 1,000 calories of their daily maintainence requirements from

oats, and the other getting 1,000 calories from wheat, the people

who used oats for energy dropped their blood levels of low-density

lipoprotein cholesterol (LDL or " bad " cholesterol) by 23 mg/per

deciliter, and the wheat eaters dropped LDL by 13 mg/dL. In

addition, at the end of the six week study period, the oat eaters

lowered their systolic blood pressure by 7 millimeters of mercury,

and the wheat eaters showed a lowering of 2 mm/Hg. The reseachers

speculate that the bood chemistry improvement and lower blood

pressure are due to the soluble fibre. Oats contain more soluble

fibre than wheat. They speculate that the soluble fiber slows down

the rate of both digestion and absorbtion, slowing the release of

insulin, high rates of release of which is implicated in blood

pressure rise in some people. There may also be 'unidentified

factors' in oats which have a beneficial effect on blood vessels.

 

Women eating a diet that included 1.3 'servings' of 'whole grains'

had about a 30 to 40% lower risk rate of ischemic stroke, relative

to the women whose 'normal' intake was a half a serving of whole

grains per day. So boosting intake of natural grains to even one

serving per day has a powerful stroke protective effect. What

particular attribute of grains in gneral, or their effect on

metabolism, that is so helpful isn't known. But some useful chemical

constituents have been identified.

 

Plants contain a class of common natural chemicals

called 'Isoprenoids'. They help regulate such things as seed

germination, and plant growth. Grain seeds contain an isoprenoid

called 'gamma-tocotrienol', chemically somewhat similar to vitamin

E. Laboratory experiments on the growth of human leukemia and breast

cancer cell lines showed that the cancer lines growth was three

times slower compared to a normal human cell culture which received

the same dose of isoprenoid. The important point is that the

experiment used a dose of isoprenoids that anyone might be able to

be obtain from eating a standard natural diet.

 

Recent (1998) research has shown that nitric oxide in the body has a

protective effect on the integrity of the blood vessels. An amino

acid, arginine, is the main source of nitric oxide in the body.

Peanuts, sesame seeds and sunflower seeds are the richest sources of

arginine, along with meat and nuts. The arginine content of wild

legumes and nuts in the African and Asian ancestral environment has

not been reported (except for the Southern African manketti nut,

which has the highest concentration of all, with 3.5 mg/100 mg -

peanuts are the next highest with 2.8mg/100 grams). Arginine is said

to also be useful in treating some cases of 'penile hypotumescence'.

Ahem.

 

The natural 'phytochemicals' known as 'phenols' and 'polyphenols'

are hypothesized to be responsible for reducing the risk of cancers

in people who eat sufficient fruit and vegetables. The various kinds

of polyphenols have a variety of protective modes of action -

carcinogen compound blocking, antioxidant and free radical

scavenging, and tumour proliferation repression. While the phenols

in fruit, black tea, red wine, and vegetables are well known, few

know that in fact barley, at 1,200 to 1,500mg/100gms, and some forms

of sorghum, (at up to 10,260mg/100 grams) have by far the highest

amounts of any foods -other than dried figs (around 1,000mg per

100grams of product).

 

Domestication of Seeds

People are quick to seize new technologies - that is a major reason

we are so successful. So the initial wild grasses and legumes that

had already been domesticated acted as a sort of 'pre-emptive

strike' against the domestication of other perfectly edible wild

species. Once the advantages of growing these 'new technology' seeds

was apparent, wild harvesting (and thus the possibility of

domestication) of other equally promising species effectively ended.

That is why we eat dried peas, Pisum sativum, and not the equally

good, closely related species Pisum fulvum. The same effect

prevented any of the other numerous edible relatives of flax,

barley, lentils, or chickpeas being domesticated. It's not that they

weren't good enough. They just weren't first.

Domestication of seeds meant that on average, vastly more people

could live per square kilometre than if the same space was used for

gathering and hunting. Increased births resulted in pressure for

more land, more forest was cleared for seeds, and continues to be

cleared today.

 

'Millets'

This is a slightly dismissive term used by European colonialists to

describe predominantly African and Asian grains that Europeans

themselves didn't ordinarily eat. It includes 'common' or 'broom-

corn' millet Panicum miliaceum, the shiny seed usually fed to

budgies in the west; 'foxtail millet' Setaria viridis var. italica,

an Asian species domesticated in China for at least 2,500 years and

used in the west primarily as 'millet sprays' for your budgie cage

(a native middle Americas species, S. parviflora, was almost

domesticated by 3,500 years ago, but was abandoned as maize

emerged) ; 'Japanese millet' Echinochloa frumentacea a very fast

maturing grass seed widespread in many climatic zones of South East

Asia; but not much now used; 'pearl' or 'bulrush millet' Pennisetum

typhoides a white seeded millet on a bulrush-like head, which,

unlike bulrushes, is adapted to semi arid areas and probably

originated in the Sudan or immediate sub Saharan Africa ; 'finger

millet' Eleusine coracana, a species native to tropical east Africa,

is a short stemmed, dry land adapted, millet with excellent storage

characteristics and an outstanding mineral content, and is still a

staple in parts of central and eastern Africa; and 'sorghum' Sorghum

bicolor, from Ethiopia a relatively large seeded drought resistant

millet that doesn't keep well. It was probably domesticated in

Ethiopia or Central Africa, initially maybe around 5,000 years ago,

and carried to West Africa, perhaps 3,000 years ago, where it was

further developed by the Mande people, especially the high quality

white seeded forms (red grained types are bitter).

 

Various species of Panicum, or 'panic' grasses, are indiginous to

Africa. In South East Africa, possibly the cradle of the human

species, there are at least seven species- Panicum aequinerve, P.

deustum, P. ecklonii, P. hymeniochilum, P. maximum,

P. natalense, and P. subalbidum. Westerners who chose to eat a

primarily grain and seed based diet consider Panicum the most

digestible of all seeds, and the best suited to human nutrition.

Given our long evolutionary association with this grass seed, it is

not suprising.

 

'Millet' farming has been dated to 7,500 years ago in Northern

China, so it seems likely that consumption of wild millets has been

going on for many millenia prior to that date in Asia.

 

These grains are primarily dry-land adapted, are generally low

yielding, but very tough. They don't have the high productivity of

temperate grains such as wheat, and are much smaller seeded (except

for sorghum). But they make life possible in drought prone,

difficult areas.

 

Presumably Europeans don't eat millet because it has no gluten and

can't be made into a bread.

 

Finger Millet, Eleusine coracana - A very good page covering the

origin, distribution, nutrient analysis, ecology and more.

http://www.hort.purdue.edu/newcrop/duke_energy/Eleusine_coracana.html

 

 

Finger Millet, Eleusine coracana - an online re-presentation of the

section on finger millet in 'Lost Crops of Africa: Volume I:

Grains' (1996), including an outline drawing of the seeding plant.

http://books.nap.edu/books/0309049903/html/38.html

 

Foxtail millets, Setaria sp. - an Iowa State University page on

their weed potential also has put up good photographs of the seed

heads-foxtail millet S. viridis var. Italica; yellow foxtail S.

glauca; knotweed, S. parviflora; giant foxtail S. faberi ; and

Bristly foxtail

S. verticillata

http://www.agron.iastate.edu/~weeds/Ag317-99/id/WeedID/Ffox.html

 

JoAnn Guest

mrsjo-

www.geocities.com/mrsjoguest/