28 de Outubro, 2009
Dr. Staffan Lindeberg explica porque os cereais “saudáveis” da civilização, afinal, não são assim tão saudáveis quanto isso, porque o ácido fítico destes se agrega aos minerais, formando sais insolúveis (fitatos), diminuindo assim a absorção daqueles por este mecanismo. Os cereais dão assim importante contributo para a deficiência em ferro tão tipica da civilização
Autor: O Primitivo. Categoria: Primitivos| Saúde
Foto: Cereais, um alimento neolítico/moderno,
somente possível com a agricultura.
Subject: Raw foods, esp cereals
From: Staffan Lindeberg
Date: Mon, 31 Mar 1997 03:15:21 +0100
Since all contemporary human populations appear equally intelligent, I find it a bit hard to believe that the ability to control fire is not at least as old as man himself, that is more than 150,000 years. Whether the need to use it was there is perhaps a more difficult question.
Whatever the use of fire during human evolution, the concept of making grains or beans edible by way of soaking, souring and fermenting needs further consideration. Whole meal cereals and other seeds as well as beans have in their shells phytic acid which strongly binds to minerals like calcium, iron, zinc and magnesium to form insoluble salts, phytates. There is overwhelming evidence that whole meal cereals through this mechanism decrease the absorption of such minerals. In this way cereals are an important contributing cause of iron deficiency in third world countries and possibly in the western world.
As to calcium deficiency the picture is less clear. Mellanby found back in the 30s that dogs got rickets when they were fed oats from early age. The possible absence of rickets in preagricultural skeletons, its apparent increase during medieval urbanization and its epidemic explosion during Western European industrialisation can hardly be explained only in terms of decreasing exposure to sunlight and decreased length of breast-feeding, nor to sub-optimal intake of foods rich in vitamin D or calcium. An possible contributing cause is a secular trend of increasing inhibition of calcium absorption by phytate from cereals since these apparently increased in amount during the Middle Ages, and since old methods of reducing the phytate content such as dampening and heat treatment may have been lost during the emergence of large-scale cereal processing from the agricultural revolution. Old fashion sourdough baking decreases the amount of phytic acid by use of phytases, enzymes which are also found in the cereals but which often are destroyed during industrial processing.
Non-westernized Melanesians from Kitava, Trobriand islands, that we have surveyed had four times higher magnesium levels in hair compared to Swedes, Asian Indians and westernized Polynesians of Tokelau (the latter three groups had similar levels) while those of zinc were two-fold higher in Kitavans. whether the very low phytate intake in Kitava (they do not eat cereals) is involved remains speculative.
The claimed notion of members of the raw food community that it might take a week or two for your digestive tract to adjust to raw cereals finds to my knowledge no support in the scientific literature, and then I’m exclusively referring to phytates.
As to other potential dangers of cereals, I have not much to say in this context, but Loren certainly has, though he may want to wait until after publication of his extremely interesting paper on cereals to come.
Let me know if you want references.
Staffan
Fonte: PaleoDiet Archives.
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