The food of the third millennium: meat or cereals? PART 3
I’ll show a short presentation of prof. D. Joe Millward.
Even at this moment, proteins sources from plants provides 65% of protein consumed worldwide, most coming from cereals, the rest from vegetables, nuts and seeds.
From cereals, wheat provides 43%; rice, 39%; and corn, 12% of proteins of plant origin. Although many evidence suggests that plants can provide all the necessary proteins for human, persists the wrong idea that, in terms of nutrition, plant proteins are lower than those from animals. This conception is the result of some special cultural and social attitudes vs. meat.
In fact, nowadays, the important question is not whether plant proteins can fully meet the requirements of amino acids the human body needs, because is known that plant proteins provides all the amino acids, in absolute sufficient quantity for all age groups, but if such a thing can be made for populations in poor countries only with cheap cereals grown there.
Usually, it’s forgotten that wheat and corn are ” rich protein food “, when compared to breast milk and if not taken into consideration the energy density. Thus, feeding based on cereals, especially wheat, can give even more than we need to meet the proteins requirements that the human needs in all groups of age.
Regarding infants and children, the wide and successful use of milk and soy products has shown that the pure vegetarian alimentation can be appropriate for them too.
In the medicine treatments, we find that malnutrition syndrome or nutritional morass described in african children, in 1933, under the term kwashiorkor, is due to the diet rich in carbohydrates and lacking in protein. But in 1997, Golden has shown that kwashiorkor is not a disease caused by the lack of protein.
Today, nutritionists agree that the alimentation with vegetable products, which can be obtained in most regions of the world, provide enough protein for all ages. So, the amount is not a problem.
In the past, there were objections related to protein of vegetable origin digestibility. Now is known that, once the vegetable cell walls constituents are removed, the inherent digestibility of vegetable origin proteins does NOT distinguishes from the proteins of animal origin.
What was considered less digestible, for example, 80-90% whole grains, peas, husked rice, soybean flour and chickpeas, 50-80%, millet and beans, particularly referring to the walls cellsespecially resistant of the plant , and not on the actual proteins.
Studies on children in Peru showed that protein from plant sources digestibility, compared with casein, was 100% wheat, 90% corn, 82% potato and rice and 81% for and beans.
Regarding to the essential amino acids, the main difference between the plant nutrient sources and the protein content of human tissues consists in lysine content. The question is: How significant are these differences?
Research conducted on children have shown that the biological value of potato proteins or some corn hybrids is comparable to that of breast milk, even if the level of lysine is lower than in human tissues.
And in the American Journal of Clinical Nutrition (2000; 72: 113-121) Millward and his collaborators published results of the study on the use of lysine, showing that the human body has coping mechanisms for lysine conservation using lysine intracellular stores and by its synthesizing by the microbial flora. All this makes that lysine needs to be more lower than assumed so far, so wheat protein can be used by the body more efficiently than previously believed.
Different milk nutrients proportions show the needs of the newborn, whether it’s a child or an animal. While breast milk contains 1.2 g protein per 100 g, cow’s milk has 3.3 g / dl, and the rat, 11.8 g / dl. It’s clear that the human needs, from birth, fewer proteins than animals, and these proteins can be obtained from cereals, in sufficient quantities without the need for animal products. And if we know that in the poorest countries are consumed vegetables, seeds, nuts and fruit, then we realize that the most economical way to feed the world population is the vegetarian.