Article found at www.drfuhrman.com
What
You Need to Know About Vegetarian or Vegan Diets
Following
a strict vegetarian diet is not as important as eating a diet rich in fruits
and vegetables.
All types of diets—vegetarian or
non-vegetarian--have potential health risks as well as associated benefits. My
patients frequently ask me questions about the most nutritious foods, and
positive aspects and the dangers of different types of diets, particularly
vegetarian and vegan.
As a start, we can define the various types of
diets in these ways:
Vegan |
Consists
totally of plant foods, with no dairy, eggs, or other foods of animal origin. |
Vegetarian |
Avoids
eating animals, but may or may not include some dairy, eggs or other products
of animal origin. |
Omnivorous |
Utilizes
both animal products and plant foods |
Lacto-ovo-vegetarian |
Contains
no meat, fowl, or fish, but allows eggs and dairy products |
Is a vegetarian or vegan diet the
healthiest diet for my family?
When
looking for the healthiest diet, people often consider vegetarian diets. But are vegetarian diets the healthiest diets? There
are two things we all know with certainty. First of all, more nutritious food,
such as vegetables, beans, fruits, raw nuts, and seeds in the diet have
dramatic effects at reducing the risk of both heart disease and most cancers.
The other thing we know is that as animal products increase in a population’s
diet, the risk of both heart disease and cancer increase. It has been observed
in multiple scientific studies that vegetarians have fewer heart attacks and
less incidence of cancer than those on omnivorous diets.
The chief feature that makes a vegetarian diet
beneficial compared to more conventional ways of eating is that a person
following a vegetarian diet is likelier to be consuming more high nutrient
produce that contains protective fibers and antioxidant nutrients. This diet
will naturally be lower in saturated fat, which is an accepted risk factor for
both heart disease and cancer.
Not surprisingly, fruits and vegetables are
the two nutritious foods with the highest correlation with longevity in humans.
Not whole wheat bread, not bran, not even a vegetarian diet shows as powerful a
correlation with decreased mortality as does a high level of fresh fruit and
raw green salad consumption1. The National Cancer
Institute recently reported on 337 different studies, with all showing the same
basic information:2
1.
Vegetables
and fruit protect against all types of cancers if consumed in large enough
quantities. Thousands of scientific studies document this. The most prevalent
cancers in our country are primarily a plant-food deficiency disease.
2.
Raw
vegetables have the most powerful anti-cancer properties of all foods.
3.
Beans,
in general, and not just soy, have additional anti-cancer benefits against
reproductive cancers, like breast and prostate cancer.
Clearly, the chief health reason to choose a
vegetarian diet is to consume high levels of fruit, green vegetables, and
beans. A diet primarily comprised of nutritious foods, not processed food or
animal products is the key both to better health, and healthy weight loss.
People often ask me whether it is absolutely
necessary to follow a vegetarian diet. Let me stress this: Following a
strict vegetarian diet is not as important as eating a diet rich in fruits and
vegetables.
A vegetarian whose diet is mainly refined
grains, cold breakfast cereals, processed health food store products,
vegetarian fast foods, white rice, and pasta will be worse off than a person
who eats a little turkey, chicken, fish, or eggs but consumes large volumes of
fruits, vegetables, and beans. That combination of little or no animal products
with a higher consumption of fresh produce is the crucial factor that makes a
vegetarian diet healthful.
Research has confirmed this. Multiple studies
have shown that vegetarians live longer than non-vegetarians do3. The research shows
those who avoid meat and dairy have lower rates of heart disease, cancer, high
blood pressure, diabetes, and obesity, which are the leading causes of death in
America4.
But when we take a close look at the data, it
appears that those who weren’t as strict with their diets as the vegetarians
had longevity statistics that were equally impressive -- as long as they
consumed high volumes of a variety of unrefined plant foods.
So the question is: can the total protection
offered by increasing the nutritious foods - the high phytochemical/antioxidant
(protective plant foods)-- to make ones diet produce-predominant be achieved,
even if the diet is not totally vegetarian and includes some animal products? I
think the answer is yes. In other words, you can achieve the benefits of a
vegetarian diet, without being a vegetarian or a vegan, and the science
available seems to support this.
So let’s not debate whether it is all right to
eat a little bit of animal food or not. The main focus here that cannot be
contradicted or disagreed with is: Whether you eat a vegan or vegetarian diet
or you include a small amount of animal foods you must get the majority of
calories from unrefined plant food for optimal health. A large quantity of
unrefined plant food grants the greatest protection against developing serious
disease.
A strict vegetarian diet, then, may be the
healthiest diet, but it also may not be. One can choose to be on a healthy
vegetarian diet, with careful planning; and one can choose to be on a healthy
omnivorous diet, with careful planning too. Both ways of eating still require
knowledge about the most nutritious food to eat to assure excellent health and
disease protection.
What are the drawbacks of a vegetarian
diet?
A strict
vegetarian or vegan diet is deficient in meeting the nutrient needs of most
individuals for vitamin B12. If you choose to follow a complete vegetarian or
vegan diet, it is essential you consume a multivitamin or consume a B12 source,
such as fortified soymilk.
Vitamin D, often called the sunshine vitamin, is another common deficiency in
those not drinking vitamin D fortified milk. Synthetic vitamin D is added to
both cow’s milk and most brands of soy milk today.
Most of us work indoors and avoid the sun or
wear sunscreens, which lowers our vitamin D exposure. Some of us live in
northern climates, are not outdoors as much, don’t absorb it as well, or may just
require more. It is important to assure your vitamin D requirements are met
sufficiently.
It is a myth that a vegetarian diet, rich in
green vegetables, beans, and whole grains would be likely to be low in calcium
or protein. Plant food contains adequate levels of these nutrients. However, if
a vegetarian diet is not carefully designed to include foods such as nuts,
seeds, green vegetables, beans, and whole grains, then levels of calcium, iron,
zinc, and protein could be low.
For example, iron deficiency anemia has been
reported in some macrobiotic vegetarians who followed a very restrictive diet
and consumed a diet with rice as their staple food. This would not have
occurred if these individuals ate more green vegetables and beans which contain
adequate iron.
Likewise, if vegetarians and vegans eat a
variety of plant proteins, their intake of protein should be as good as that of
a person who eats meat or other foods that contain animal protein. The mixture
of proteins from grains, legumes, seeds, nuts, and vegetables provides a
complement of amino acids so that deficits in one food are made up by another.
Not all types of plant foods need to be eaten at the same meal, since the amino
acids are combined in the body's protein pool. So there is no need to mix or
match amino acids to form complete protein at each meal; your body can do that
on its own from what you consume all day.
Keep in mind that it is not a vegetarian diet
per say that is low in these mentioned nutrients; it is just that some who
indiscriminately drop animal products from their diet may not substitute enough
of the nutrient-rich plant foods to make the diet adequate. You can be a
vegetarian, yet be a vegjunktarian with a poor diet.
Although a low-saturated-fat vegan diet may
markedly reduce risk for coronary heart disease, diabetes, and many common
cancers, the real Achilles heel of the low-fat vegan diet is the increased risk
of hemorrhagic (vessel rupture leading to bleeding) stroke. Apparently the
atherosclerotic (plaque building) process that creates a local vascular
environment favorable to coronary thrombosis (clot) and intravascular embolism
(traveling clot) may be protecting the fragile blood vessels in the brain from
rupture under years of stress from high blood pressure. Admittedly, hemorrhagic
stroke is a very small percentage of the deaths in modern countries. It still
is worth noting that if strict vegetarians are to have the potential to
maximize their lifespan, it is even more important they avoid a high salt
intake because salt intake increases blood pressure. Almost all of the soy
based meat analogues and many other health food store (vegan) products are
exceptionally high in sodium.
A number of studies both in Japan (where the
high salt diet had made stroke a leading cause of death) and the West have
illustrated that less animal products and a low serum cholesterol was
associated with an increased risk of hemorrhagic stroke5. The high
salt->high blood pressure ->stroke causation chain may be more likely a
late life event in a vegetarian successfully maintaining excellent heart
health. So avoiding excess sodium may be even more important for a vegetarian
than an omnivore. Of course, excess sodium increases both heart attack and
stroke death in all diet-styles, but in a vegan, the high-salt diet is even
more likely to rear its ugly head as a cause of late life morbidity and
mortality. Especially since vegans often live longer and will not likely have a
fatal heart attack at a relatively young age. Obviously, dying prematurely of a
heart attack would preclude having a stroke at a later point in life, because
you are dead already.
Keep in mind, stroke mortality is
significantly higher in Japan and exceptionally high in certain areas of China
where salt intake is high, in spite of low fat diets. It is also well
established that populations in Third World countries which do not salt their
food are virtually immune to hypertension, the age-related rise in blood
pressure we see in 90 percent of Americans and the incidence of strokes.
And lastly, another concern is that many
vegetarians may not have ideal levels of all essential fatty acids. Fish supply
two non-essential fatty acids (EPA and DHA) that have been shown to have
beneficial effects, offering protection against both heart disease and aging of
the brain. To assure that vegetarians get sufficient levels of these omega-3
fats, people on vegetarian diets need to consume foods such as flax seeds, hemp
seeds, and walnuts on a regular basis. The body can then manufacture the longer
chain fats typically found in fish.
Some individuals may still not have optimal
levels of long chain omega-3 fats, even with the consumption of a well designed
vegetarian diet utilizing these seeds and nuts, therefore I recommend
vegetarians and those not eating fish regularly consume a DHA supplement.
I also recommend that all individuals--vegetarian or not-- consume a daily
multivitamin.
What are the drawbacks of an omnivorous
diet?
Despite the availability of nutritious foods,
much of the modern developed world today eats a much less than optimal diet. In
fact, the incidence of heart disease and cancer is higher in more developed
countries and still kills about 80% of all adults, despite the fact that the
nutritional causes of these illnesses have been explained by scientific
studies.
Unfortunately, our society has developed to the point where half of all caloric
intake today comes from refined or processed foods and about 40 percent from
animal products. Both processed food and animal products lead to heart disease
and cancer, according to scientific literature.
The most commercially successful diet books in
our country appeal to America’s love-affair with saturated, fat-rich animal
products and still leave the public with a relatively dangerous solution to
their growing waistlines. These books encourage a higher percentage of animal
products in people’s diets in spite of the preponderance of evidence showing
the links to heart disease and cancer.
There are three main problems with diets that
contain significant amounts of animal products:
1.
More
than a thousand well-designed studies have led to all major health authorities
around the world to conclude that saturated fat is a leading contributor to
high cholesterol, heart disease, and many cancers. In spite of that, some still
believe the earth is flat, and saturated fat is not harmful.
2.
Fat
soluble petrochemicals such as PCB’s and dioxin, as well as other toxic
elements such as mercury are transferred to humans predominantly via the fatty
portions of fish, dairy, meat, and poultry and in that order. Fatty fish that
are rich sources of omega-3 fats are also typically heavily contaminated with
harmful pollutants.
3.
Animal
products contain no fiber, and almost no antioxidant vitamins such as vitamins
C, K, E and folate. They also are lacking in all the anti-cancer
phytochemicals, bioflavonoids, lignins, and carotenoids that are so essential
to protect us against chronic illnesses, immune system disorders, and a
premature death.
With animal products occupying a major caloric
percentage of the diet, less remains for natural, unrefined plant produce,
nutritious foods essential to our health. The inclusion of sugar, white flour,
oil and other low-nutrient calories in an omnivorous diet virtually guarantees
phytonutrient deficiency and the occurrence of late life cancer. So the low
levels of certain essential nutrients are inevitable, unless an omnivorous diet
is carefully designed to include substantial amounts of fresh fruits,
vegetables, beans, raw nuts, and seeds to supply crucial food elements for
optimal health.
The amount of produce necessary to afford a
considerable degree of protection would automatically necessitate animal
products be a significantly smaller percentage of ones dietary intake, rather
than a main portion. After that, the type of animal products chosen is crucial
to minimize their potential harmful effects. The animal products that are
lowest in saturated fat are egg whites, low fat fish, skinless white meat
turkey, and chicken. The highest saturated fat animal products are butter,
cheeses, and red meat.
Because animal products do not contain
significant omega-3 fat it is important for those omnivorous diet to consume
walnuts, flax, hemp, and other plant sources of omega-3. The valuable omega-3
fats should not be derived exclusively from the regular consumption of fatty
fish, which are such a polluted food. Instead, I recommend the lower fat (less
polluted) fish such as flounder, sole, and tilapia and using the cleaner, plant
sources of omega-3.
In addition, a multivitamin and a DHA
supplement would still be a good idea, for the assurance that optimal levels of
these nutrients are met.
Is a vegetarian or vegan diet safe for
children?
Parents often
ask me whether their children should be eating a vegetarian or vegan diet. A
diet optimally designed for the human species, would naturally be ideal for the
children of that species too. There are no special needs children have that
would make them require a different diet. Even at the time of rapid growth and
brain development the optimal supply of energy and essential fats can be met by
and appropriately planned vegetarian or vegan diet.
According to the American Dietetic Association
and the Institute of Food Technologists vegan diets can provide adequate
nutrition for children.
In May 1998, the seventh edition of Dr.
Spock's Baby and Child Care was published. In it, Dr. Spock recommends a
vegan diet for children. Dr. Spock was concerned that the diet we fed our
children, rich in animal products and dairy fat set them up for adult
disabilities and a premature death. He wasn’t wrong. But this sparked a long
overdue discussion about the scientific and practical issues of optimal diets
for children.
Clearly children of all ages need an adequate
supply of healthy fats to fuel their growth and energy needs and for brain
development. Some people believe even a B12 supplemented vegan or vegetarian
diet would not supply enough essential fats for comfort. This could be a
concern if the diet is essentially carbohydrate-based, comprised of foods such
as bread, potato, rice and fruit.
Conversely, raw nuts, seeds and avocados are
rich in protein, fat, vitamins and minerals. Whole nuts, such as peanuts,
should be avoided in young children as the shape makes them possible to get
stuck in a toddler’s windpipe, if not chewed. But nuts can be safely utilized
in the diet after one year of age utilizing nut butters, dressing, sauces and
desserts to meet these concerns of fat adequacy.
Nuts are rich in protein and also a clean
source of nourishment as they grow on deep-rooted trees and do not contain
chemical residue. Avocados are appropriate food for infants starting at six
months and can be mashed with bananas and mixed with other foods to add a
nutritious fat source. The addition of fortified soy milks and tofu, beans, and
green vegetables assures complete nutrition for toddlers and children on
vegetarian diets.
Of course, informed parents know that if
children are to maximize their intellectual and health potential they must be
breast fed. Breast feeding should be continued to at least the first and
preferably the second birthday to maximize benefits at reducing cancer
incidence for both the baby and the mother doing the nursing.
The real question: Is an omnivorous diet
safe for children?
Clearly the
omnivorous diet that most children consume today is particularly dangerous to
their future health.
The most recent scientific evidence is both
overwhelming and shocking—apparently what our parents choose to feed or not
feed their children during childhood has a greater effect on the cause of
certain cancers than dietary intake over the next 50 years.
Today it is well recognized that our children
eat less than 2% of their diet from natural plant foods such as fruits and
vegetables. American children move into adulthood eating 90% of their caloric
intake from dairy products, white flour, sugar, and oil. Then many develop
autoimmune illnesses as young adults before heart disease and cancer strikes
later. Diseases of nutritional ignorance flourish, but they have not been
connected to their cause—childhood diets—until now. The diet rich in cheese,
whole milk, white flour and sugar is implicated.
High dairy fat and animal food consumption in
childhood assures unnaturally high levels of hormone promoters that raise our
children’s blood level of estrogen and testosterone, induce an earlier
maturity, and initiate changes that promote adult cancers. It is well accepted
that an earlier puberty significantly increase the adult risk of both prostate
and breast cancer. Animal fats (especially dairy and fish) also contain
contaminants that place children at increased risk.
One could make an omnivorous diet safer if
dairy fat were removed, if one avoided the potential pollutants in fish, if
processed food were significantly limited and if an abundance of produce were
consumed. I would rather a young child added eggs to her diet than fish or
dairy, because of the potential for transmission of chemicals mercury and PCB’s
in the fish and dairy.
Therefore I encourage consumption of a
carefully planned vegetarian diet or one that includes a small amount of animal
products, perhaps 10% of total calories or less, rather than 40 -60 % that
children eat today. An animal-product-rich omnivorous diet cannot be considered
nutritious food or called healthful.
If one is to utilize animal products in their
family and children’s diet they should only choose low-fat or nonfat varieties
of dairy products, if they are included in the diet at all. I still recommend
substituting nuts, seeds, and avocados as the major sources of fat in the diet.
Fruits, vegetables, avocados, nuts, seeds,
beans/legumes, and whole grains are the optimal foods for children. Here are
some of the long-term advantages of plant-based diets:
Here are some of the long-term advantages of
plant-based, vegetarian diets:
Summary
Both vegetarian and omnivorous and diets can be made healthful or harmful;
nutritious food choices, wise supplementation and nutritional sophistication
will make the difference in the type of diet you choose. Following a strict vegetarian diet
is not as important as eating a diet rich in fruits and vegetables. Inclusion of high nutrient produce, including nuts,
seeds, fruits, vegetables and beans are an essential part of every healthy
diet.
Related Links
Gentle Care Formula: A completely vegan multivitamin formulation developed
by Dr. Fuhrman, providing balanced antioxidant protection. [click here]
DHA Purity: A vegetable-derived DHA that is manufactured with a
unique freeze-dried process to preserve freshness. [click here]
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