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Protein
The most common question you will get from concerned loved ones
(and sometimes even doctors!) who know you are reducing your meat
consumption will be: “But where will you get your protein?” This
is an area where our knowledge has indeed come a long way. Protein
deficiency, unless caused by an extreme restriction in calories
(as in starvation or eating disorders) or a particularly poor diet
devoid of variety, is rare.
Consider these facts:
• Most people in developed countries eat too much protein (often
double the RDA, which already has a safety margin built into it).
• High protein intake increases excretion of calcium in the urine,
which can contribute to a negative calcium balance and bone loss,
which can lead to osteoporosis.
• Excess animal protein, which is often high in saturated fat
and cholesterol, raises blood cholesterol levels, and can contribute
to heart disease, kidney disease and osteoporosis.
• Nuts and legumes are excellent sources of protein and have many
other benefits as well.
• It is not at all necessary to “combine” plant proteins at the
same time or even at the same meal in order to get adequate protein.
• Since many plant foods contain protein, eating enough calories
and a variety of foods will ensure adequate protein intake.
• Legumes are an excellent source of lysine, which is the most
common amino acid lacking in people who consume very little protein.
Iron
Americans who eat a meat-centered diet get most of their iron from
meat. But iron is widely available in plant foods, too. The absorption
of iron is greatly increased by ascorbic acid (vitamin C), which
is found in many fruits and vegetables. Good plant sources of iron
include dried beans, tofu, whole grains, dark green vegetables such
as spinach and other greens, dried fruits, prune juice, blackstrap
molasses and fortified breads and cereals. Including foods that
are high in vitamin C, such as fruits or juices, broccoli, tomatoes,
green or red peppers etc., along with iron-containing foods, helps
your body absorb the iron. Dairy foods, on the other hand, are low
in iron and tend to inhibit its absorption. Thus, it is not uncommon
for people who replace meat with dairy products to become iron deficient.
It is important to replace iron-rich animal foods with iron-rich
plant foods to reduce risk of iron deficiency.
The high amount of iron consumed in meat-based diets can actually
be a problem for many people. While iron deficiency is a big nutritional
problem worldwide, hereditary iron overload (hemochromatosis) in
men is much more common than iron-deficiency anemia. Even people
without this faulty iron-storage gene typically build up iron in
their bodies as they age. And too much iron can contribute to heart
disease by acting as a pro-oxidant (the opposite of the protective
anti-oxidant).
“Animal source food is adaptive when there’s not enough
food, but in a world with abundant and diverse plant foods,
animal source food is obsolete and only causes problems.”
-- William Harris, M.D.
Calcium
While we are all very much aware of the high calcium content in
dairy products, they are not our only source of calcium, nor are
they our healthiest source. Many plant foods offer abundant, available
calcium, and now many non-dairy beverages, such as orange juice
and soy milk are fortified with calcium to the same level as cow’s
milk. Good calcium sources include dark green leafy vegetables such
as kale, mustard greens, bok choy, and broccoli. (Note that not
all dark green vegetables—especially spinach and collard greens—are
good sources of calcium because their availability for absorption
is poor.) Tofu prepared with calcium, some beans, and some nuts
(such as almonds) and seeds (such as sesame seeds) are also good
sources.
The reason that dairy isn’t our healthiest source of calcium is
that it comes with a lot of “baggage”: saturated fat, cholesterol,
genetically-engineered growth hormones and antibiotics. When you
trade a glass of milk for a cup of steamed broccoli, not only do
you avoid all that baggage, but you get all of the benefits of that
plant: vitamins, fiber, phytochemicals and anti-oxidants.
“You have just dined, and however scrupulously the slaughterhouse
is concealed in the graceful distance of miles, there is complicity.”
-- Ralph Waldo Emerson in Fate
Fats
Saturated fats
Saturated fats have been shown to be a big dietary contributor
to high blood cholesterol levels. The main sources of saturated
fat include animal fat, dairy fat, tropical oils, and cocoa butter.
Trans fats
Margarine, shortening and many processed foods contain hydrogenated
oil. The process of hydrogenating oil creates these trans fats,
or “funny fats.” Because trans fats increase LDL (“bad” cholesterol),
decrease HDL (“good”cholesterol) and raise triglycerides, they are
the worst kind of fat to consume. Trans fats appear to be 2-4 times
worse for the risk of coronary artery disease than even saturated
fats. (16) Look closely at the labels of peanut butter, burritos
and processed foods such as chips and cookies, and try to avoid
“hydrogenated” or “partially hydrogenated” ingredients.
Monounsaturated fats
These “good” fats are found in high percentages in olive oil,
canola oil, avocados, olives, and nuts. Research has shown that
replacing saturated fats with monounsaturated fats can be effective
in lowering LDL (“bad”) cholesterol levels. These fats are also
believed to be the best fats to consume to reduce your risk of certain
types of cancers.
Polyunsaturated fats
These fats have received both praise and criticism for their effects
on health and disease. The essential fatty acids—needed in order
to maintain good health—include two poly-unsaturated fatty acids:
linoleic acid (an omega-6 fatty acid) and alpha-linolenic acid (an
omega-3 fatty acid).
It is important to consume both omega-3 fatty acids and omega-6
fatty acids. The typical American dietary pattern provides excessive
amounts of omega-6 fatty acids in relation to omega-3 fatty acids.
Current research suggests that essential fatty acid levels and balance
may play a critical role not only in growth and development, but
also in the prevention and treatment of chronic diseases, including
coronary artery disease, hypertension, type-II diabetes, arthritis,
other immune/ inflammatory disorders, cancer, and psychological
disorders such as depression, Alzheimer’s disease, schizophrenia
and ADHD.
Plant sources of omega-6 polyunsaturated fats include corn oil,
sunflower oil and safflower oil. Omega-3 fatty acids are found in
canola oil, flaxseeds and flaxseed oil, walnuts and hempseed oil.
Research has shown that omega-3 fatty acids aid in preventing thrombosis
and coronary artery disease, and may be helpful in reducing inflammation
in arthritis. For this reason, it is important to insure adequate
essential fatty acid intake and balance by….
1. reducing intake of saturated fat (found mostly in animal
foods) and trans fats (found in processed foods and margarine);
2. avoiding omega-6-rich oils (corn oil, safflower oil,
sunflower oil);
3. if using oils, select those rich in monounsaturated
fats (olive oil and canola oil);
4. including a daily source of omega-3s (walnuts, flaxseeds,
greens); and
5. making whole foods (nuts, seeds, avocados) your primary
source of fat, instead of oils.
"I don't understand why asking people to eat a well-balanced
vegetarian diet is considered drastic, while it is medically
conservative to cut people open and put them on powerful cholesterol-lowering
drugs for the rest of their lives." -- Dean Ornish, MD
Vitamin D
In most climates and for most people, 15 to 20 minutes of exposure
to the sun alone is ample to meet needs for vitamin D. If supplementation
is desired or needed (for those who are housebound, who have dark
skin, or who live in northern climates in the winter months), vitamin
D-fortified milk alternatives are good sources of this vitamin,
or one can take a vitamin D supplement.
Vitamin B-12
Vitamin B-12 is produced by microorganisms, bacteria, fungi and
algae. Neither plants nor animals make this vitamin. Animal foods
are sources because animals consume the B-12 in their food and/or
absorb it from B-12-producing bacteria in their intestines. Plants
may contain some B-12 (if contaminated by the bacteria), but they
are not a reliable source as most would be removed when the produce
is washed. Because of this, it is advisable in a diet devoid of
all animal foods either to take a vitamin B-12 supplement of approximately
50 mcg once a week, or to eat foods fortified with the vitamin.
Many non-dairy beverages, some breakfast cereals, some meat analogs
and some nutritional yeasts are fortified with vitamin B-12.
Zinc
Meeting recommended intakes of zinc appears to be a challenge
for vegetarians and non-vegetarians alike. Whole grains, nuts, dried
beans and tofu are good plant-based sources of zinc. Although these
same foods contain phytates that may reduce availability of zinc,
the zinc and trace mineral status of most adult vegetarians appears
to be adequate. Again, eating a variety of foods is the key.
The Bottom Line
As with any diet, a vegetarian or near-vegetarian diet should be
well-planned and balanced. Keep the intake of low-nutrient-dense
foods, such as sweets, fried foods and highly-processed foods, to
a minimum. Choose whole or unrefined grains instead of refined products
whenever possible to meet energy needs. Eat a variety of fruits
and vegetables—at least 5-10 servings per day—including a good food
source of vitamin C to enhance iron absorption. Meet your protein
needs by eating a variety of legumes, nuts and seeds, tofu, meat
substitutes and whole grains. And if you choose a vegan diet, use
a properly-fortified food source of vitamin B-12, or take a supplement.
End Notes: Works Cited
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