Got Food? - the Scientia Review

supplements and, in more serious cases, shots. Generally, however, it is possible and better to obtain B12
from a natural or semi-natural source.
The following table shows vitamin B12 content as a percentage of the RDA (only the bottom few
foods are vegetarian):
Trace Minerals in Vegetarian Diets
Aside from proteins and vitamins, trace metals, such as nickel, copper, and manganese, are also
an essential part of a complete diet. The nature of the vegetarian diet makes it easier to obtain certain
metals than others; for example, the adult vegetarian diet generally lacks zinc and selenium, whereas it
has a higher concentration of copper and manganese. In most diets, cereals are the primary source of
copper, manganese, and selenium (Gibson, 1994). However, the cereal also takes on the job of providing
zinc in a vegetarian diet, which is often inadequate by itself. While multivitamins generally contain
adequate amounts of the metals, there are many natural vegetarian sources for this missing zinc and
selenium that can be incorporated into the diet.
In most omnivorous diets, the principal sources of zinc are oysters, shellfish, liver, and muscle
meats (Weil, 2004). Selenium is generally found in fish, liver, kidney, and Brazil nuts. None of these are
vegetarian sources, with the exception of the Brazil nuts, and most of the food items that vegetarians
replace these with, fruits and vegetables, have high water contents (Gibson, 1994). Although traditional
meat substitutes like soy and tofu make up for the protein deficiency in the vegetarian diet, they do not
carry with them the minerals that animal protein sources do.
Nonetheless, meat substitutes like eggs and legumes are generally the secondary sources of zinc
in the vegetarian diet, followed by milk and dairy products. Selenium is quite different. It is rather
difficult to obtain selenium in a vegetarian diet from a source other than the Brazil nut because its other
primary source is seafood. Luckily, Brazil nuts are extremely rich in selenium and thus offer a suitable
substitute for their flesh food counterparts.
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