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Nutrients in seeds Domestication
of Seeds Domestication
Millets Rice Wheat & Barley Maize Oats Barley Rye Domestication of other annual seeds Seed eating now in the West
The human animal evolved in the forests, woodlands, and plains of Africa. The human animal spread into virtually all environments, from tropical rain forest to arid desert because that animal, which is you and me today, had evolved the kind of guts that could digest most kinds of food - plant (except woody twiglets and cellulosy grass blades) or animal. Our natural diet is everything edible. But in any given area of the world, we relied on starchy plants, nut and seed oils, or animal fat for fuel to burn for energy. Animals that know how dangerous humans are tend to run - fast, and in the opposite direction - and are fat only at certain times of year. Plants have the virtue of standing still, so underground storage tubers and carbohydrate rich seeds are a reliable energy, and in some cases, fat and protein source.The human animal evolved to eat every animal or plant that wasn't actually toxic (and, after simple treatments, some that to greater or lesser degree were). Seeds are a rich store of energy, some have good protein levels, vitamins (especially vitamin E), minerals, and protective phytochemicals. Living as wild animals for the last million years or so, we ate every seed that was worth collecting, grass seed, legume (bean-like, pea -like, peanut and others), and any other seeds that were sustaining and productive, or big enough to be worth bothering with.
Seeds were seasonal. We travelled to seed sources and ate them when they ripened, generally over a short period of time. 'Cached' seeds are hard to keep from becoming mouldy or insect ridden, unlike nuts. They have no hard shell to deter birds, and many being very small indeed, they are hard to handle. When the seasonal seed resource was too depleted to be bothered with, we moved on to another food, and didn't eat seeds until the next harvest season, nearly a year away. The fact we very recently gained the technical ability to eat seeds every day of the year is a major change for our ancient evolutionary genetic dictated biochemistry. For reasons to do with the behaviour of genes in populations as they disperse and/or become isolated in small groups, some people have not biochemically adapted to gluten containing grains - mainly wheat. Such mal-adaptations may be present for other seeds, such as maize or soya beans; or indeed for virtually any other foods, such as almonds, beef or oranges. The very small percentage of the population of the West who are gluten sensitive can relatively easily substitute grains with no gluten, such as rice. Or switch to tubers, nuts, and fruits for 'ready' carbohyrates.
Today, we have a wide range of seeds available to include in our diet, but for historical and cultural reasons Western people now eat only a few kinds of seeds, and, with the exception of beans and peas, generally eat only the carbohydrate store of the seed, leaving the vitamin, oil and mineral rich part behind.
Investing the time to change our cultural mind set to include more whole seeds of all kinds, or using canned precooked whole seeds can increase the amount of nutrients and protective plant chemicals consumed per calorie eaten, and help to displace un-natural, less nutrient dense, industrially modified foods. The result is a way of eating in harmony with the absolute needs of our ancient gene determined biochemistry. And over time, the removal of one the most important barriers to the possibility of feeling really well.
No reasonable energy source was ignored, and wild seeds were no exception. Indeed, grindstones with adherent plant starch from before 160,000 years ago - when the first recognisably modern humans appear in the fossil record - may have been used to grind grass seeds [ref]. We, of course, ate every non-toxic seed (including tree seeds) present in the environment we had moved into. There are many plants with edible seeds in the various climatic zones of Africa, but relatively few have big enough seeds, or are productive enough, to be worth expending the energy which are nicer to eat, easier to store, and require no preparation.
Of those wild African species that are worth collecting, probably the most important are the numerous species of wild 'millets' native to West and East Africa. The term 'millet' is a slightly confusing generic name to mean both 'millet' (Panicum, Setaria, Echinochloa, Eleusine, and Pennisetum spp.) and 'sorghum' (Sorghum spp.).
Early humans exploiting the riches of marsh, delta and riverine environments had access to the seeds of a reed-like grass, Phragmites autralis (communis) 'ditch reed' or 'water grass', which, although the yeild was probably relatively poor (there is little literature on this subject to form a view), had the virtue of being both widespread and in thick stands. When we migrated out of Africa, we would find this seasonal food source in damp and marshy places from the tropics to the temperate lands. These grass seeds were indeed our 'evolutionary fellow travellers'.
Numerous legume seeds were available to our African ancestors, for example the 'morama bean', Tylosema esculentum, which grows in sandy arid to semi-arid areas of the more Southern parts of Africa and tastes like cashews when roasted. In addition to having a large edible tuber, this legume has pods containing one to two oil and protein rich seeds with a nutritional value similar to soya beans or peanuts (the protein content ranges between 30% to 39% - the oil content is in the 36% to 43 % range). The widespread Acacia spp. mostly have edible and sustaining gums, but one, A. albida has seeds eaten in times of food shortage. The shrubby Bauhinia petersiana of Southern Africa is an extremely important food for several months of the year for the Kade Bushmen of the Kalahari, who gather and roast their nutritious beans. Another important legume seed for the Bushmen is 'Chivi', Guibourtia coleosperma, of the arid sandy areas of the more northern parts of Southern Africa. The pod encloses a fleshy aril from which an edible oil is extracted, and the single seed is a staple food of Bushmen, especially as they are edible for a long time after having fallen from the tree. This seed is valued by the Bushmen as second only to the mongongo (manketti) nut. Some tribes regard them only a famine food, others boil them for long periods or soak them before eating, and others merely roast them. According to an unpublished manuscript (Maguire, B 1954) quoted in 'Food from the Veldt' by F.Fox and M. Norwood-Young, the bushman eat about 25kg each per week. This quantity seems a little unlikely, and it may perhaps be 2.5kg per person per week. Anyway, these seeds are available to the tribespeople for the better part of the year. According to the authors of the previously mentioned book, the seeds of another leguminous shrub, the 'Hottentot's bean', Schotia afra, of the Cape Province of South Africa, "...were eaten by Stone Age Man." Seeds of three species in this genus have been recorded as food used by African people, both savannah and scrubby woodlands having representatives. The only African legumes to be eventually domesticated seems to be the lablab bean, the cowpea, and the guar bean.
As humans radiated out of Africa into all the regions of the world,
they exploited all food sources they came across, grasses included. In
parts of Australia, the aboriginal people regularly harvested wild
seeds (chiefly a wild 'millet', Panicum spp.), and it is likely
that given time, they would have domesticated them. Indigenous
of the grasslands of Southern South America gathered grass seeds for
and even brought one species of brome grass into cultivation. In
one of the local 'panic grasses' (Panicum spp., a kind of
was collected, and ultimately, domesticated. Palaeanthropologists have
found 19,000 year old stone mortars for grinding grain show that wild
were not just parched, but processed, from at least since that time.[ref]
Saharan wild grass harvest There is a lovely cave art picture of women gathering wild grasses in the once productive Sahara region of Africa at the Paleologos site (www.paleologos.com).
Our ancestors probably parched the whole grains on ember-heated
(this would have burnt off the adherent husks around the seed), and
a dough from the cooked flour (Tibetan people today eat a dough from
barley flour mixed with tea and yak butter and formed into a ball - tsampa).
Such doughs laid on hot stones or embers would have made the first
'bread' . Or the roasted flour could perhaps have been mixed
water to make a thin 'porridge'.
Morama Bean. J Very brief notes on the variability of protein and oil content of the wild African Morama bean. Ironically, it is being considered as a 'new food'. In fact, it may be about the 'oldest' food in the human diet.
While you 'could' eat whole rice grass seeds (for example) without parching them first, only about 25% of the proteins are able to be digested. Cook the whole seed, and about 65% of the protein is available. Grinding raw rice seeds would probably make more than 25% available, but equally, grinding and cooking would likely improve protein availablity beyond 65%. The cultural evolution of both grinding and cooking seeds brought evolutionary advantage in the form of greater access to protein - at least, for those tribal groups who had the technology.
Grass seeds, in particular, had to be heat 'parched' anyway, to get rid of the adherent woody 'chaff' covering the seed (later, with domestication, this chaff became easy to remove by beating). So a degree of 'cooking' was more necessary than a choice.
A few seeds have somewhat less protein digestability after cooking, but they are the exception. You would have to cook grass seeds at 200-280°C (392-536°F) to reduce rather than improve, their protein digestibility. Meat protein digestibility, in comparison, decreases when cooking is above only 100°C (212°F).
Seeds contain 'antinutrients' - substances such as saponins, tannins, 'protein splitting enzymes' inhibitors, and phytates. These compounds reduce the body's ability to access the nutrients in seeds. The type, and amount of anti-nutrient varies both with the species of plant, and with the local variety of the species (common beans, Phaseolus vulgaris, for example, have a wide range of phytic acid and tannin concentrations - with white seeded beans having least tannins-depending on the variety). Some have several different anti-nutrients, some have few, some have relatively a 'lot' of any one anti-nutrient, some have very little.
Most, but not all, antinutrients are destroyed or reduced by cooking. Soaking and leaching are necessary to reduce some antinutrients, particulalry in some varieties of bean and other legumes. Soaking and sprouting seeds also reduces phytates. Soybeans, for example, contain a contain a 'tryptophane inhibiter' that interferes with the absorbtion of the amino acid 'tryptophane'. The inhibitor can be neutralized both by cooking and by sprouting (the sprouted root must be 3 to 4 inches long for this to be largely complete).
A very low percentage of the starches in some seeds 'resist' being digested ( up to 7% for wheat, and oats and 20% for baked beans) These undigested starches are fermented by the microflora of the colon, producing variable quantities of gas.
Guided by the practices of recent African gatherer-hunters, it seems likely our African ancestors mainly dealt with anti-nutritional factors by roasting the seeds. Sometimes they were soaked as well, either before or after roasting (and grinding). These are classic techniques that we use even today when preparing legumes; although westerners rarely roast any other than peanut seeds, and occasionally soya seeds.
Sprouting and soaking
Sprouting seeds is a form of 'delayed gratification' far beyond the wait for the seeds to parch by the fire. It probably didn't figure in our biochemical evolution. Certainly, in very recent but pre-industrial times, legumes (particularly) were sprouted. It conserves fuel in de-forested areas, and it makes seeds reasonably palatable and much more usefully digestible. Sprouting seeds converts some of the starches to simple sugars. In grains, a simple sugar, maltose, is formed.
In the middle ages of Europe, there is some suggestion that wheat
in hot water, and left overnight by the fire to soften and 'gell'
was as common as leavened bread.
Protein builds growing bodies, and protein is made up in turn of 'building blocks' called amino acids. Grains are low in the amino acid 'lysine', which makes their protein content less useful than it would otherwise have been. 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.
Legumes, on the other hand, are very good sources of protein. Peanuts, for example, are protein rich, with about 25% or more protein content (and with a favorable amino acid profile). Lentils have about 25%, cowpeas have from 23-35%, common beans (Phaseolus) have about 22%, and so on. Legumes tend to be low in the amino acids methionine and cystine, but are high in the amino acid lysine. Lysine is low in grains, so eating the two together leverages the protein content of both. Co-incidentally, legumes such as lentils and peas tended to grow as weeds among wheat and other grains at the time they were being domesticated; in South America maize, a grain, was (and is) grown with beans, a legume. In Asia rice and Soya beans complement each other.
In conjunction with tree seeds, and to a lesser extent meat/marrow, the protein and oils of wild African legumes may have been the deciding factor in allowing humans to develop a big brain, and consequently evolve to the point where you can read this on the Internet!
Other seeds are also rich in protein. Sesame seeds are about 20% protein, altho, like grains, they are low in lysine. Mixing them with a legume such as the chickpea, Cicer arietum, (e.g. in the middle Eastern dish 'houmous') balances it out. Both sunflower seeds and pumpkin seeds are also high in protein.
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.
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.
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 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 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. The destruction of wild places to catch meat, gather nuts and fruits, meant a much narrower dietary base, more possiblity that key nutrients would be missed.
Much depended - and still depends - on cultural beliefs and practices. Maize is deficient in the B group vitamins. In Central and South America, the Indians ate it with B vitamin rich fish, avocadoes, tomatoes, peppers, and green leafy plants such as 'Malva' (depending on the region). In North America, prior to the arrival of the colonizers, it was steamed with clams, cooked with beans and meat, and generally used as a staple of a mixed diet. In some parts of Africa, maize, once introduced, overtook some of the original grains, and became heavily relied on. With increasing population pressure, it became almost a sole food, and pellagra, vitamin B deficiency, showed up.
A diet based exclusively on seeds and vegetables is not optimal; a diet based predominantly on a wide variety of seeds, roots, vegetables and nuts, with a small amount of animal or sea food is certainly one of the optimal ways of meeting human evolutionary nutritional needs.
Well, a lot of things actually. Most grasses just don't pack a large enough lunch for humans to consider them worth collecting. But in sheer production per given area, there is a lot of food going begging. We ('we' being women, no doubt) likely only collected wild grass seeds when tree seeds, meat, or starchy roots weren't available. Parts of the human population may have had to turn more and more to grass seeds as a resource as richer lands were already occupied. And there is evidence that we harvested quantities of wild grass seeds at least 12,000 years ago. We have almost certainly always eaten wild grass seeds in our evolutionary history, but probably as a short seasonal harvest, rather than a daily fare. A site ('Ohalo II') on the shores of the Sea of Galilee, in the Jordan Valley shows that we were harvesting and eating wild wheat and wild barley over 19,000 years ago, as part of a seasonally mixed diet that included fish, animals, tree seeds (acorn), fruit, and other plant parts.
Certainly, when we radiated out of Africa into the Eastern Mediterranean and South West Asia there was an annual abundance of waving grasses in the foothills - and the animals that grazed them, no doubt. Experiments with harvesting wild 'einkorn' wheat (higher in protein than domestic wheat) in Turkey showed that one hour of work yielded nearly 1 kilogram of grain. Every 1 kcal of energy expended yielded about 45 kcal of energy food. (see also below)
One thing is certain - we would have preferred the larger seeds and the more palatable seeds.Of the 23 or so edible grass seeds of the grasslands of the eastern Mediterranean, two had big seeds - relative to the rest, anyway. One was emmer, a form of wild wheat, the other was barley. Emmer had the additional advantage of the seeds not sticking to the outer husk, unlike barley (even today, barley has to be 'pearled', that is, the adherant hull abraded off mechanically). The temperate zone grasses did not spread south beyond the climatically similar Nile valley. Dryland grasses are not suited to Equatorial and Sub Equatorial Africa's humid climate and pattern of summertime rainy season.
In the hot and humid parts of Africa and Asia, the aquatic grass we call 'rice' met the prescription for larger and more palatable seeds.
Domestication of grass seeds
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
to Africa. In South East Africa, possibly the cradle of the human
there are at least seven species- Panicum aequinerve, 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.
Millet, Eleusine coracana - A very good page
the origin, distribution, nutrient analysis, ecology and more.
Millet, Eleusine coracana - an online
of the section on finger millet in 'Lost Crops of Africa: Volume
I: Grains' (1996), including an outline drawing of the seeding plant.
millets, Setaria sp. - an Iowa State
page on their weed potential also has put up good photographs of the
heads-foxtail millet S.
viridis var. Italica; yellow foxtail S.
glauca; knotweed, S.
parviflora; giant foxtail S.
faberi ; and Bristly foxtail
Unlike the dry climates of the Mediterannean and South West Asia, rice grows in hot, wet, humid climates, so evidence of it's first domestication is poor. 11,500 years is as close as we get (from archaeological sites in China's Yangtse valley, altho' this may have been wild gathered rice), for the dominant rice seed, Oryza sativa, but if the wild seeds were edible and big and productive enough to be worth gathering - and they are - you can bet they have been gathered and eaten for many millenia before that, and probably domesticated as well.
A West African rice species, Oryza glabra, was domesticated in West Africa at least 3,000 or so years ago, and is still cultivated to a diminishing extent. And when humans radiated out of Africa into South East Asia, they would have encountered the wild progenitors of O. sativa . These progenitors are thought to have been a weakly rhizomatous perennial form, O. rufipogon, giving rise to an annual form, O. nivara. This species seems to have been domesticated by the peoples of South Asia, the warmer part of East Asia, and the Northern part of South East Asia. The cultivation of this pond edge marginal grass over a wide geographic range, taking in many different soils and seasonal variations has resulted in the very variable O. sativa that is cultivated today.
The native African rice also seems to have probably arisen from a rhizomatous perennial ancestor, O. longistaminata, also giving rise to an annual species, O.barthii, ultimately becoming the cultivated O. glaberrima.
The Asian and the African rice are very similar in form, but
distinct (hybrids between the two species are sterile). The African
varieties are now rapidly being replaced by highly bred Asian
Wheat & Barley
Yields of wild wheats are high relative to the energy expended. In a famous experiment in the later 60's, a botanist used a flint sickle to harvest wild cereals in their natural range. He harvested 1.8 kilograms /4 lbs in an hour. A few weeks' work would have yielded enough grain for one family for a year. Just how many families the wild grain resource of that area could have supported - annual fluctuations aside - is uncertain. But relatively large quantities could be harvested. In some ways, the problem was what to do next. 'Cache' the excess in one place, guard it, and scrape by on whatever other alternative food sources there were until the next harvest? Or eat only a portion of what was there in the grain season, then move on? The first strategy would require semi permanent settlement, and this seems to be be what eventually happened. Settled camps are also defensive units, and it would have made sense to make sure the immediate environment was growing plenty of wild grasses, so the tribe's women and children didn't become dangerously exposed, and didn't have too far to carry the harvest.
Gatherer hunters are acute observers of the natural world, and it wouldn't take a big leap of understanding to hit upon both planting harvested seeds close to home, and perhaps choosing the best sorts from the wild population. And when gathering and re-sowing grains over many years, there is a 'drift' towards those that retain their seeds on the head, and that have the most grains on the grass head. Genes for these attributes tend to accumulate by unconcious and conscious human selection at harvest time, as well. This, then, was probably how Europeans came to be eating these particular grass seeds.
Tribespeople living in the dry Mediterranean climate these grasses grew in obviously didn't just eat grass seeds. They would have eaten animals large and small, other seeds of annual plants, nuts, and fruit. Upland grass meadows are, by definition, relatively devoid of trees, including seed bearing trees such as nuts. So grass seeds may have been the major carbohydrate source for the local tribes. The seeds would have been a good source of protein, altho' limited by low levels of one of the essential amino acids (lysine). These limiting amino acids could have been 'made up' by other seeds that mature at the same time, such as lentils (or other legumes such as peas). Grass seeds contain oil, vitamin E, and some other vitamins and minerals, except for vitamin C. So they are a very good framework from which to flesh out a diet for health and growth.
These domesticated seed producing grasses soon spread west and east to European and Asian countries of a similar latitude. In a span of about 8,000 years or so, grass seeds went from domestication in the eastern Mediterranean and the Tigris-Euphrates river valley region of Iraq to a situation where the seeds were being grown for food from Ireland to Japan. And that is in prehistoric times, a time of relatively low population, with no modern infrastructure or communications other than trade trails and war parties. This is an example of a technology so 'hot' that its benefits needed no selling.
The temperate zone grasses did not spread south beyond the climatically similar Nile valley. Dryland grasses are not suited to Equatorial and Sub Equatorial Africa's humid climate and pattern of summertime rainy season.
Wild 'einkorn' wheat, Triticum boeoticum, became the cultivated T. monococcum, still not much different from the wild progenitor, and fairly low yielding. Einkorn wheat is still in cultivation, but in almost imperceptible quantity. Goatgrasses, a group of weedy, very small-seeded Triticum species with a high gluten content and wide ranging climatic adaptability crossed naturally (perhaps even as weeds of our early crops of einkorn wheat) with einkorn to give rise to a series of species known as the 'emmer' wheats. Wild emmer has been identified from at least 10,000 years ago. One emmer, T. dicoccum, is still grown, albeit in small amounts. Emmer wheats have hulls on the seeds that have to be winnowed off. Modern wheats arose from the emmer by mutation in chromosome number. Of these, one, 'spelt' formerly the main wheat of Europe, has grains with hulls, but another, T. aestivum, has naked seeds that fall free from the wheat head. These are now the preferred wheat for bread.
wheatgrass in southwest Asia - a good factsheet on
a dryland wild wheat relative that our ancestors may well have
It appears to have "no functional gluten", and has similar levels of
substances to wheat'.
history of the domestication of wheat - A New York
article relating the probable story of domestication of wheat, in the
of 'einkorn' wheat, Triticum monococcum monococcum.
'Maize', Zea mays, and another wild grass 'Teosinthe', Zea mexicana lived in the same region of South America (Mexico and Guatemala) and were probably derived from the same common ancestor. Over the millenia, the very hard grained but 'poppable' teosinthe probably crossed with maize, creating a seed head with more worthwhile characteristics.
Native Indians first wild harvested this variable seeding grass, then later domesticated it. The earliest evidence for domestication is from about 12,000 years ago, but evidence of any kind is sparse this far back. Early forms were very small, with very small kernels, and were probably a hard kernelled 'popcorn'.
From these early forms, came larger hard kernelled types with a small soft floury core-'flint' corns. 'Dent' corn has a larger floury core, which shrinks as the grain dries, forming a 'dent' on the surface. Floury corns have little hard endosperm, and were preferred by the Indians for cooking. They have smooth kernels, and may be brown, white, pink, red, yellow, purple, streaked, or speckled.
Maize seeds were (and are) ground to flour to make a flat bread cooked on the embers, the ears were roasted whole, steamed in an earth oven; the dry grains were soaked in wood ash and lime to remove the hull, then dried and ground to make thin flat breads (tortillas). Immature green corn was eaten in earliest times, and the fungal fruiting bodies of 'corn smut' a serious fungal disease of maize, were eaten (and still are by those who know). Even the pollen was sometimes added to stews.
Oats, Avena sativa and A.byzantina, are a grass seed of temperate climates with a good rainfall (although there is a dryland African species, A. abyssinica in Ethiopia). The cultivated species probably evolved from a weedy grass ancestor, A. sterilis, a present day major grass of the hills of the Mediterranean and South West Asia. The larger seeded crop species are very close genetically to the ancestor. It is believed that oats were initially a weed in wheat crops as wheat pushed into central Europe and beyond. As wheat reached its northern European limit, the oats thrived where the wheat didn't, and from this switch, domestication of oats developed. That oats were a less worthwhile seed than other grasses is evidenced by archaeologists finding emmer and einkorn wheat, pulses and barley at sites 8,000 years old in South West Asia, but not oats. Oats don't appear in the archaeological record until about 3,000 years ago, and then not in their native South West Asia, but in Europe.
Like barley and flax seeds, oats are one of the few seeds that grow well in a moister, colder climate. And oats are particularly useful for the cold of northern climates, because not only do they have good protein content (about 16%), but they are also a valuable source of fat (about 8%).
Another South West Asian grass seed we would have been confronted with as we migrated out of Africa, barley, Hordeum vulgare, is valuable because it is very cold hardy, growing up into the Arctic, and growing at high elevations in the mountains. The husk is tightly adherent to the seed, and our ancestors no doubt would have had to parch it off. (Today it is mechanically abraded off, a process known as 'pearling').
Barley originated from the wild H. spontaneum (H. vulgare is strictly the same species), widespread in Eastern Mediterranean and South West Asia. Archaeological finds of 10,000 year old remains in these regions may be from wild harvested seeds, or may have been the beginnings of cultivation, nobody knows. By 8,000 years ago, 'improved' varieties appear, and it became probably the most important grass seed -far more important than wheat - until only about 2,000 years ago, when wheat more or less replaced it.
Curiously, it had the reputation for being a 'strong' food; it was awarded to the champions at the Eleusian games, and gladiators were called 'hordearii', 'barley men', because that was the chief component of their training diet.
Like oats and barley, rye, Secale cereale, is a relatively unimportant seed in the big picture of human diet, in that it is a 'second choice' seed used mainly because of it's adaptation to poor soil and very cold conditions. Like oats, it appears late in the history of human domestication of grasses, and linked to life in the colder, more marginal climates of northern Europe.
Again like oats, it was probably selected from weeds in wheat crops, as wheat pushed into the limits of its climatic adaptation. Another case of 'the wheat crop failed yet again, but at least we got those weed seeds. Maybe we should forget the wheat and grow the weeds!'
The very particular downside of this grass seed is that, like most grasses, it is parasitised by a fungus - but this fungus (ergot, Claviceps purpurea) has poisonous, not edible, fruiting bodies. In fact bread made from heavily contaminated rye seeds can cause hallucinations, gangrene, or abortions, amongst other unpleasantness.
What is known is that in what is present day Botswana, the people raised 'millets' (perhaps Sorghum spp.), a legume similar to the pigeon pea, and a small, spotted type of bean. According to the European commentator (1801), the 'millet' and legumes of these cattle raising peoples were usually boiled together in milk, or 'broiled' (? parched on hot stones).
Roasting legume seeds seems to be a major way that hunter gatherers prepared them. Some species were soaked in water first, or the outer seed skin was removed. But even these practices varied between different tribes (today, some tribes peel the seed coat off the introduced South American bean, the 'lima bean', before cooking them, and some don't).
As noted above, Africa has many edible legumes, mainly shrubs and small trees. Only three, the lablab bean, Dolichos lablab (a perennial climber), the 'guar bean', Cyamopsis tetragonolobus, and the 'cow pea', Vigna unguiculata, have been fully domesticated, even tho' there are 66 species of Vigna indigenous to Africa for example, and numerous other legumes, some of which, at least, might also be suitable candidates for domestication. Outstanding candidates are the 'morama bean', Tylosema esculentum, (mentioned above), and a peanut look-alike, the Bambarra groundnut, Voandzeia subterranea native to tropical Africa .
It is suspected that the cowpea was domesticated 5,000-6,000 years ago, probably in Ethiopia, and in conjuction with the domestication of sorghum, Sorghum bicolor. Obviously, it would have been an important dietary item for a long time before that.
The 'guar' or 'cluster' bean has a very interesting galactomannan gum in the seed. Its presumed predecesor, C. senegalensis, is native to drier areas of west Africa. That it was used as human food in Africa is strongly suggested by the fact that it was introduced to Southern India, probably by Arab traders.
Generally, introduced 'beans', Phaseolus vulgaris, Vigna radiata (mung bean), Soya bean, Glycine max; and peanuts Arachis hypogaea, have surplanted them.
Soya beans were selected by early agriculturalists in Asia, and have been cultivated for at least 2,000 years. Given our long evolutionary history of use of legumes, it is unsurprising this bushy annual was so highly valued.
Lentils and peas grew in the same South West Asian/East Mediterranean region as wheat, and when one was domesticated, the other came with it, possibly initially as a weed in the cereal crop. Lentil remains have been found in early settlements of about 8,000 years ago. It is not certain whether they had been gathered from the wild, or were from a crop. By 6,000 years ago, seeds that are larger than the wild forms are found - a strong indicator of domestication.
When we radiated down into central and South America, we soon came to appreciate, and domesticate, the wild phaseolus species (P. vulgaris, the common bean, P. lunatus, the lima bean, and P. coccineus, the scarlet runner) we found there.
The other big 'find' was a useful legume, the peanut, one of the 40
or so species of Arachis in South America, but with a complex
background that resulted in it being big and productive enough to be
human attention. It was probably domesticated by tribes in the Andean
of Southern Bolivia. From there, it spread with Indian tribes
South America as far as Mexico and the Caribbean, such was its value.
The seed coat is tightly adherent, and has to be abraded or parched off. It is claimed that buckwheat contains "dyes" which, when consumption is heavy enough, are activated by exposure to light to produce skin irritation in the exposed area.
Of the 36 or so species in the genus Sesamum, two thirds are indigenous to Africa. S. angustifolium, S. radiatum, and Ceratotheca sesamoides (same family as sesame, different genus) are still grown to a very limited extent in Africa. One species, S. indicum, is the main commercial crop. It is not found in the wild, so its origin is obscure, but it probably arose from the species S. capense and S. grandiflorum, which are native to Africa, South Asia, and South East Asia.
Everywhere, it has been highly valued for its rich, oily seeds. The outer seed coat is tightly adherent, which meant it would have to have been ground to make it edible. Sesame is a low yeilding plant, and the fact it is harvested and has been domesticated attests to the value that humans place on oil rich foods.
Archaeological evidence shows sesame in India about 4,000 years ago, and East Mediterranean and South West Asia from at least 6,000 years ago.
Due to its small seed size and poor productivity, it has not been a mainstay of a domesticated human diet, but more a highly valued adjunct.
Flax seed (linseed)
Flax is a widespread annual plant of temperate and warm temperate North Africa and Eurasia. Linum usitatissimum, the domesticated flax, may be derived from the biennial L. angustifolium of South West Asia and Southern Europe. This is a very variable species, and some presently described species, such as Linum africanum, may in fact be L. angustifolium. Either way, this very plastic and variable seed plant will have long been a part of our evolutionary history.
South West Asia seems to have been the major centre of diversity for useful seeded forms, and it is thought that flax spread north and west fromýÿÿÿ‚
Similarly, rice is stripped of its nutrient rich outer coat (bran) in the interests of a softer whiter product, albeit a nutritionally gutted product our ancestors did not have the technology to create. The main vitamin lost is B1(thiamine)- white rice has ten times less of this vitamin than the whole seed (brown rice). And what nutrient factor is absolutely essential for carbohydrate metabolism? Thiamine.
Culturally, people in the west don't make or use flat breads. The seed we overwhelmingly eat, the wheat seed, is turned into a 'biological foam' by fermenting it with carbon dioxide producing yeasts. The biofoam is then stabilised with heat. The result is the stabilised biofoam of wheat seed carbohydrate that we call 'bread'. This biofoam has best 'mouth feel' if it is made from the depleted, nutrient stripped seed ('white flour'). It is estimated that of the 200 pounds of grain seeds eaten annually by the average American, 95% is nutrient stripped (and artificially 're-fortified' with a few of the originally stripped nutrients), and only 5% is derived from the whole grain nature 'intended' us to eat!
Why is wheat seed biofoam more common than most other seed biofoams? Because wheat seed has a particular kind of protein in it called 'gluten', which can form a light springy mass when fermented with yeast. Removing the bran makes it even softer and 'melt in the mouth'. Most other grass seeds either don't have this protein, or don't have much of it (oats and rye have some gluten), and their biofoams are not very foamy, they are dense and solid. 'We don't like to chew, but we sure like to swallow', as the old saying goes!
Much has been made of 'gluten intolerance'. Some people are allergic to gluten ( it is more prevalent in women than men, and because it is genetically determined, it's prevalence varies between about 1 person in 300 in Western Ireland and 1 in 2,000 for Europe in general); but the gassiness, fatigue, depression, and stomach discomfort can be quickly eliminated by eating other grass seeds such as rice, or millet which contain no gluten.
Gluten intolerance is primarily a genetic predisposition, probably involving several genes, and has persisted at a very low level, probably ever since a small portion of the human species inhabited South West Asia and the Eastern Mediterannean. The levels of gluten in the local perennial and annual wheat type grasses were low, and likely didn't provoke much of an auto-immune reaction in most new immigrants; and for those in whom it did, there was much likely to be malabsorbtion of food, poorer nutritional status overall, maybe diarrhoea, complications and either death or poor reproduction, hitting children especially hard.
In other words, those indivduals whose genes caused them to react severely to the low levels of gluten in the grains tended to disappear from the local gene pool, leaving a population well adapted to wheat eating, but with a small number who reacted to gluten without showing symptoms, or who had relatively inconsequential symptoms, as the amount of gluten in wild grains was not high.
But cultivated wheats have much higher gluten content than their
parents. It may be that modern wheat is more likely to tip the immune
(of those already genetically pre-disposed) into a reaction. One
estimate is around .5% overall in Europe -
( still a high actual number of people) exhibit symptoms of some degree, and maybe 5% being 'silent carriers' of the genes (not exhibiting symptoms, but demonstrating a biochemical reaction to gluten when tested, and perhaps a potential for reaction to triggered off at some stage in their life).
So most of the European population of South East European descent show no bad effect from eating gluten containing grains; and those most recently introduced to glutens, as in Ireland, having more people who react. Having a west European background doesn't mean that you are gluten sensitive; it simply means you are more likely to be one of the small percentage of gluten sensitive people.
The genes will live on at a low level within the European population, but with the mixing of various populations the level of the genes in the population may shift either higher or lower, depending on a variety of difficult to predict interplaying factors. Gluten intolerance will never 'go away', each individual is biochemically distinct. Some of us have to learn to listen to the intelligence of our our own biochemistry.
The seeds we eat are chosen more for convenience and because of cultural norms, not because we 'have' to eat any one particular seed to have a healthy diet. Most people are tolerant of most foods, including grass seeds of all kinds. Some people have food allergies of greater or less importance (one estimate is 10% of the population). These allergies traverse virtually all foods, from beef to wheat, peanuts to oranges. The consequences range from mild gut disturbance, to, in a tiny minority of cases, anaphylactic allergy reaction and death. 90% or more of us have no food allergy (not all digestive effects are caused by allergy-because beans cause gas doesn't equate to allergy!).
People in the west today have seeds from Mediterranean-like climates in both the new and old world - wheat, rye, barley, maize, flax, garbanzo/chickpeas, lentils, peas, sesame. We have seeds from tropical and subtropical climates - rice, sorghum, peanuts. We have temperate climate seeds - barley, oats. Some of these seeds are available only in health food stores. Some are preground, some whole, some pre-cooked and canned. We can easily mimic the diverse seed eating of our ancestors because the seeds are available. The main reasons for eating seeds are cultural (convenience) and very recent, not evolutionary. Tubers and roots could be substituted, or green bananas, or nuts. But for 90% or more of the population, there is no reason to.
As always, to the extent we re-culturate to eat freshly ground whole seeds, or sprouted seeds, or biofoams with soaked whole seeds, or boiled whole seeds, freshly roasted /parched whole seeds, then we are eating the foods we evolved to eat; and we will obtain the oils, vitamins, minerals, fibres, phytochemicals the cells of our bodies unconditionally require. This natural way of eating creates the pre-conditions for a healthy life, all other lifestyle factors not limiting.
Reading & notes
Lost Crops of Africa: Volume I: Grains Board on Science and Technology for International Development, National Research Council 408 pages , 6 x 9, 1996. Available by mailorder at: http://www.nap.edu/catalog/2305.html
 Ofer Bar-Yosef, in an article in Evolutionary Anthropology, 1998:161, dates the Kebaran sickles somewhere between 18,000 and 14,500 years before present, and puts stone mortars for grinding wild grains at about 19,000 years before present
Catassi C, Ratsch IM, Fabiani E, Rossini M, Bordicchia F, Candela
F, Coppa GV, Giorgi PL: Coeliac Disease in
the year 2000: exploring the iceberg.
Lancet, 1994, 343: 200-203.
Greco L, Maki M, Di Donato F, Visakorpi JK. Epidemiology of
Disease in Europe and the Mediterranean area. A summary report on the
study by the European Society of Paediatric Gastroenterology and
In "Common Food Intolerances 1: Epidemiology of Coeliac Disease",
S, Visakorpi JK, editors, Karger, Basel, 1992, pp 14-24
Van Peer et al. 2003 'The Early to Middle Stone Age Transition and the Emergence of Modern Human Behaviour at site 8-B-11, Sai Island, Sudan'
Journal of Human Evolution Vol 45. pp 187–193
Paper Reading-list of books & scientific papers to buy or find at the library (links to internet sources of the book or paper are included where available)
Form your own opinion on these matters after reading widely and consulting appropriate professional advice, including advice of medical practitioners and professional nutritionists.
Remember, there are many 'crackpot' sites on the Internet, and, although I don't believe this is one of them, it is only my opinion!