VEGAN VS VEGETARIAN
Vegan vs. Vegetarian
There are many similarities between Vegan and Vegetarian diets, and a few differences. We all must consume food for energy, growth and repair - without it, we would eventually perish! However, many of us follow certain cultural, health-oriented, moral, spiritual, or combination ways of eating. Some of the dietary trends that are discussed and debated in the media or by health practitioners include Veganism & Vegetarianism.
Vegetarianism is the dietary practice of consuming foods that are mostly plant-based, including: fruits, vegetables, grains, sprouts, nuts, and seeds. An individual who practices strict vegetarianism does not eat meat, chicken, or fish, and sometimes other animal products - often for moral, religious, and/or health reasons. Individuals often begin a vegetarian diet for moral reasons, because they have decided that the killing of and consumption of dead animals is wrong and immoral.
Other individuals choose to begin this new way of eating for health reasons, such as: trying to reduce their consumption of cooked saturated fat, which is largely found in animal fat; as well as trying to reduce their consumption of cholesterol, which is only found in animal products.
If one is practicing as a lacto-vegetarian or an ovo-vegetarian, they may still consume dairy and egg products, respectively. In a more moderate approach to vegetarianism, some vegetarians like to avoid the heavier and harder to digest animal proteins of meat and poultry, but still consume the lighter texture of fish protein; they are called pesco-vegetarians.
Vegan vs. Vegetarian – Veganism is a stricter version of vegetarianism. The vegan will not consume any food or food product that once was a living animal or is derived from a living animal (such as honey from bees). Quite often, vegans practice this way of life for strong moral reasons.
Pros: For heart patients or others on a strict low saturated fat and low cholesterol diet (even though most blood cholesterol levels are affected not by direct intake of cholesterol but by the production of cholesterol via the liver from predominantly saturated fat intake), it can be a wise decision to cut down on saturated fat and cholesterol intake via a vegetarian diet. ‘Whole food-based’ vegetarian diets tend to contain more colorful fruits and vegetables, and, therefore, provide an assortment of healthy nutrients, including: anti-oxidants; phyto-chemicals; enzymes (if raw or low-temperature prepared, below approx. 116 °F); fiber; prebiotics; and sometimes probiotics. Magnesium and potassium rich fruits and vegetables can provide an alkaline residue which protects against bone loss. This alkaline residue is especially important to the aging kidney which has a problem handling excess acid. Vitamin K-rich leafy green vegetables facilitate the formation of the essential bone protein osteocalcin. If practicing as a lacto- or ovo-vegetarian or especially as a pesco-vegetarian, one could also receive some nutrients that are more difficult, though not impossible, to consume through a strict vegetarian or a vegan diet, such as B12 and DHA & EPA omega 3 fatty acids. [In addition, a vegetarian and a less strict vegan can now obtain DHA from microalgae supplements.]
Cons: A possible deficiency of: vitamins B2, B6, & B12, vitamin D, calcium, heme iron, DHA & EPA omega 3 fatty acids may occur if an individual is a very strict vegetarian, a vegan and/or not supplementing with these nutrients. In addition, a possible protein deficiency (if not mindful enough of incorporating rich sources of mixed plant-based proteins or adding protein supplements to one’s diet) may also occur. The amino acid pool (the building blocks of protein) present in a vegan and sometimes in a strict vegetarian diet may not be as balanced as the amino acid pool from protein obtained from animal sources. The missing or low amino acids in some vegan or vegetarian protein sources are referred to as the rate limiting amino acids. 
|Protein source||Limiting amino acid|
|Legumes||Tryptophan or Methionine (or Cysteine)|
|Maize||Lysine and Tryptophan|
|Egg||none; the reference for absorbable protein|
The biochemistry of vegetarian vs. animal-based foods:
The mineral ratios (potassium / sodium, or calcium / phosphorus) of vegetarian verses animal-based foods also deserves attention as they can have a favorable or unfavorable effect on someone’s health. Kidney and liver chemistry are some of the more precise ways to evaluate the decision on whether a patient would benefit more from an omnivorous (meat and plant eating) or a vegetarian diet. Individuals who predominantly exhibit lower levels of iron, protein, phosphorus, sodium, and manganese, and higher levels of potassium and zinc are better candidates for diets with a greater emphasis on meat, while those with a tendency for higher levels of the above (iron, protein, phosphorus, sodium, and manganese) and lower levels of zinc and potassium are better candidates to adopt vegetarianism, and they should reduce or avoid animal-based food sources as much as possible.
With some medical problems (renal failure), a primarily vegetarian-based diet becomes almost mandatory, but even then certain types of foods, (i.e., those that are oxalic acid-rich – berries, celery, spinach, almonds, pecans, etc), would have to be avoided. On the other hand, patients exhibiting very high levels of cellular potassium or zinc, and are, therefore, at a greater risk of developing genitor-urinary conditions, including ovarian / testicular cancer, should avoid strict vegan-types of diets that tend to promote much higher cellular levels of both these elements.
John Friedstein, CNReferences:  http://en.wikipedia.org/wiki/Essential_amino_acid#Essentiality_vs._conditional_essentiality_in_humans  www.acu-cell.com