Page 44 - Spring2013

Adequate vegetarians are twice as likely and vegans are is six times richer. Thus, most omnivores may
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three times as likely to have elevated homo- stand to gain substantial improvements in mental
glutathione cysteine. Figure 5 provides a resolution to this health by including glycine-rich skin and bones
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status paradox: while vegetarians and vegans may (in the form of bone broth) in their diets.
generate less homocysteine, they also have lower Moreover, Figure 5 shows that folate assists
protects intakes of vitamin B , which is needed to recycle vitamin B in its support of the methylation pro-
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against homocysteine back to methionine. cess. Folate is found primarily in legumes, leafy
Indeed, using the highest quality markers greens and liver. Vegetarians tend to consume
degenerative of vitamin B status, investigators have esti- more leafy greens and legumes than omnivores,
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diseases of all mated that up to 73 percent of vegetarians and and most omnivores fail to take advantage of
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kinds. up to 90 percent of vegans are deficient in B . liver or other organ meats. Many omnivores may
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This should be unsurprising since vitamin B is thus improve their mental health even further by
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found almost exclusively in animal products, and including folate-rich plant foods and liver in their
even that which occurs in eggs, a key vegetarian diets.
source of animal protein, is poorly bioavailable. 16
Thus, methylation takes a double-whammy: less HARNESSING GOOD NUTRITION
methionine is available to begin with, and what FROM ALL SOURCES
is available often gets trapped as homocysteine Vegetarians and vegans may adhere
rather than being recycled. more strongly than omnivores to other health-
Figure 5 provides another key part of the promoting habits as well. This is especially
balance. When methionine concentrations rise, important to consider if we are interested in
for example after eating a protein-rich meal, the preventing all diseases rather than just mental
amino acid glycine acts as a buffer to prevent disorders. For example, Figure 5 shows that
excessive methylation. Although animal foods glycine helps convert homocysteine to gluta-
are not richer in glycine than plant foods as a thione, the master antioxidant and detoxifier of
proportion of total protein, a diet that includes the cell, and a key regulator of protein function.
animal products provides more glycine than one We might predict from this that vegetarians and
that does not simply because it is richer in total vegans should have lower glutathione status than
protein. omnivores because of lower intakes of methio-
Vegetarians excrete almost twice the level nine and glycine.
of a unique marker of glycine deficiency in their Some studies, however, have shown that
urine as omnivores. This suggests that exclud- while vegans have lower glutathione status than
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ing animal products from the diet could not only omnivores, vegetarians have slightly higher glu-
lead to a generally inadequate level of meth- tathione status. Unlike the vegans, the vegetar-
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ylation because of lower intakes of methionine ians in such studies may have been consuming
and vitamin B , but the lower intake of glycine plenty of milk and eggs. Thus, the vegetarians
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could also lead to transient periods of excessive and omnivores may have had similar intakes of
methylation. This could theoretically result in methionine and glycine. Both the vegetarians and
seesawing between excessive mental stability vegans may have been consuming more fruits
and excessive mental flexibility. and vegetables. These provide vitamin C, which
The purpose of this article, however, is not spares glutathione from oxidation, polyphenols,
to denigrate vegetarian diets but to emphasize which increase the production of glutathione,
the importance of nutrient-dense animal foods. and, especially in their raw state, glutathione
A standard omnivorous diet is hardly the ideal. itself.
Even omnivores excrete substantial amounts of Adequate glutathione status protects against
the marker of glycine deficiency discussed above degenerative diseases of all kinds. The best way
in their urine. This could be because the typical to support glutathione status would likely be to
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omnivore fails to make use of skin and bones in consume a traditional diet that includes plenty of
their diet. Protein from skin is three times richer nutrient-dense foods of all kinds: meat, organs,
in glycine than meat, while protein from bones bones, skin, folate-rich legumes and leafy greens,
44 Wise Traditions SPRING 2013 SPRING 2013 Wise Traditions