Monday, December 9, 2013

Phytates: Antinutrient or Essential Nutrient?

'Paleo' and low-carbohydrate diet advocates often claim that humans can't obtain adequate nutrition from a plant-based diet because plants have too many so-called antinutrients. For example, in their paper "Man The Fat Hunter" Ben-Dor et al write:

"Nuts, or other high-quality foods of decent size appear only seasonally above ground in the savanna and such is the case in the Levant, too. But not only are they seasonal, they also require laborious collection and most of them contain phytic acid [phytate] that inhibits the absorption of contained minerals. These foods also contain anti-nutrients and toxins such as trypsin, amylase and protease inhibitors as well as tannins, oxalate, and alkaloids the elimination of which can only be achieved (sometimes only partially) by pre-consumption processing like drying, soaking, sprouting, pounding, roasting, baking, boiling and fermentation."

As I wrote in Powered By Plants: Natural Selection & Human Nutrition:

"Whether any of the so-called anti-nutrients has any harmful effects in humans depends entirely on whether humans have specific metabolic adaptations to these compounds."
In Powered By Plants: Natural Selection & Human Nutrition I have a section devoted to one of these "antinutrients": tannins. Animals naturally adapted to plant-based diets produce salivary proline-rich proteins, which neutralize the anti-nutritive effects of tannins. About 70% of the proteins in human saliva consist of proline-rich proteins. Moreover, humans seem to have a 'taste' or preference for tannin-rich foods such as tea, herbs, spices, chocolate, beer, and smoked foods. Thus we have clear evidence that humans have an evolved adaptation to tannins, which negates their claimed antinutrient effects.

Read more....

1 comment:

Elizabeth said...

Very interesting!!! I really enjoyed learning many new things, thank you for sharing your knowledge.
Peace & Raw Health,
Elizabeth