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ing tofu provides the same nutritional value as eating pork, beef, salmon contains more essential amino acids than beans
or chicken. Tofu is especially deficient in methionine and tryptophan. for five of the nine amino acids, but beans can
As shown in Figure 7, various parts of the egg contain different por- help balance the corn in the other four areas. That
tions of the essential amino acids. Many people just eat one part of the egg, is why beans and corn are often served together
the white or the yolk, for ostensibly better health. If you just eat the white in the Mexican diet, for example. Those who
of the egg, you’ll get less nutritional value than available from either the eat only vegetable proteins need to pay careful
yolk or the whole egg. The white contains only protein, but no vitamins attention to the amount of amino acids in each
or minerals. If you eat just the yolk, you’ll get less of one essential amino source to make sure they have enough overall.
acid, tryptophan (number 8), than from either the white or the whole egg. Figure 11 compares two incomplete pro-
The egg yolk also contains vitamins, minerals and important fatty acids. teins—navy beans and wheat bread—with a
For maximum nutritional value, it’s best to eat the whole egg. complete protein, in this case chicken. You can
clearly see the superiority of chicken in provid-
PROTEIN FROM PLANTS ing the essential amino acids. Yet the first two
Plant foods do not provide the same quality protein as animal foods. items, wheat bread and navy beans, are those the
First, we focus on wheat, an incomplete protein. The amino acid amount in USDA recommends as sources of amino acids to
the whole wheat kernel is greater than in wheat flour, whole wheat bread, substitute for meat, milk and eggs. This figure
and white bread. Wheat is lower in tryptophan (number 8) than is needed. illustrates why such advice is faulty. It is a myth
The longest bars in Figure 8 indicate that the wheat kernel contains more to say all protein sources are equal.
of the nine amino acids than wheat flour, and that whole wheat bread The incomplete proteins from grains and
contains more of the amino acids than white bread. Most of us eat wheat other plant sources—corn, rice, peas, beans, nuts
in bread, either of the whole wheat or the white bread variety, not a whole and sesame seeds—contain all nine essential
wheat kernel. Figure 8 illustrates the fact that the grains we currently eat amino acids but not in the same amounts and not
do not furnish enough protein to be a major source of protein in our diet. in adequate amounts as found in eggs, dairy prod-
Figure 9 illustrates our concern with the lower amounts of essential ucts and meat. However, as we showed above,
amino acids in grains versus animal products. Here the comparison is it is possible to obtain the nine essential amino
between the protein in whole wheat kernels, a form most of us do not eat, acids, piecemeal fashion, by eating several kinds
and egg. Note how much more of the amino acids are in the complete of vegetable protein, like grains and legumes, at
protein, egg, versus the incomplete protein, wheat. the same time. It is true that if you eat an extra
The amounts of amino acids in 100 grams of navy beans and corn are large amount of the incomplete proteins, you can
compared in Figure 10. As shown, both are low in tryptophan (number 8) get 100 percent of what you need. However, you
and methionine (number 5). Corn is also low in lysine (number 4). Corn may not have a large enough stomach to eat any-

FIGURE 7: Comparison of equal amounts of FIGURE 8: Amino acids in whole wheat kernel, wheat flour, whole wheat
egg white, egg yolk and whole eggs. 1 bread and white bread. 1

Egg white Egg yolk Egg whole White Bread Wheat Flour Wheat Bread Whole Wheat

1. Histidine; 2. Isoleucine; 3. Leucine; 4. Lysine; 5. Methionine g Cystine; 6. Phenylalanine g Tyrosine; 7. Threonine; 8. Tryptophan; 9. Valine g/100g
38 Wise Traditions FALL 2011 FALL 2011 Wise Traditions

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