Facts you should know about vegetarian and vegan diets
All kinds of vegetarian diets can be nutritionally balanced, but it will take some planning to do this.
To eat meat, or not to eat meat… This is the question on many people's minds. The negative impact of animal foods on health, the damage associated with animal foods and the environment, religious beliefs, and the desire to protect and respect animals are some of the reasons for the increase in the number of people consuming vegetarian diets. Many people express an interest in consuming a vegetarian diet but don't do so because they are unsure of how to do it or are not ready to give up meat. Fortunately, there are options and lots of great resources available to help. The key to making this diet work for you is to understand what nutrients you are missing from the foods that you are not consuming and to learn how to balance your meals without these foods.
What types of vegetarian diets are there?
Only plant-based foods
Meat
Poultry
Fish
Milk
Eggs
Cheese
Honey
*Also avoid: leather, fur, silk, wool, soaps, and cosmetics derived from
animal product
Plant-based foods
Milk
Milk products
- Cheese
- Yogurt
Meat
Poultry
Fish
Eggs
Plant-based foods
Milk
Milk products
- Cheese
- Yogurt
Eggs
Meat
Poultry
Fish
Plant-based foods
Occasionally consume or consume in limited quantity any or all of the following:
- Meat
- Poultry
- Fish
Animals foods
consumed in limited quantity and/or frequency
What are the potential dangers from consuming the various kinds of vegetarian and vegan diets?
Cutting out meat is not all that it takes to follow a vegetarian diet. You need to remember that whenever you omit a food group you could potentially be missing some essential nutrients. All kinds of vegetarian diets can be nutritionally balanced, but it will take some planning to do this. Numerous studies have shown that poor meal planning is the cause of nutritional deficiencies in vegetarian diets, not the absence of animal foods. Well-balanced vegetarian diets have been approved for all stages of life, including pregnant and lactating women,
children, adolescents, the elderly population, and competitive athletes.
The nutrients for which you are at risk of not getting enough will depend on
the foods that you have omitted from your diet. The following are the most common nutrients that
may be lacking in a vegetarian diet.
Omega-3 fatty acids
The American Heart Association recommends “consuming fish (particularly fatty
fish) at least two times a week.” The fat in fish provides the essential omega-3
fatty acids, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA). The
omega-3 supplements and the foods fortified with it have varying amount of EPA
and/or DHA. Omega-3 fatty acids have been shown to slow the progression of
atherosclerosis, reduce triglyceride levels, act as an anti-inflammatory agent,
possibly help with depression and other personality disorders, and possibly thin
the blood. There is ongoing research to determine if there are other health
benefits.
To a limited extent, your body can produce EPA from alpha-linolenic acid (ALA), another essential fatty acid. According to studies, ALA does not produce any
DHA, so it does not provide comparable health benefits to omega-3 fatty acids.
ALA can be found in nonmeat sources such as flaxseed oil, flaxseeds, canola
oil, walnuts, and tofu. Research has shown that microalgae oil can serve as a
source of omega-3 fatty acids for vegans and vegetarians. Microalgae oil is rich
in DHA like fatty fish and provides an adequate amount of EPA.
One other thing to take into consideration when trying to obtain the health
benefits from omega-3 fatty acids is the amount of omega-6 fatty acids that you
are consuming. Omega-6 fatty acids are the other essential fat in our diet.
These fatty acids are found in abundance in our diets. So much so, that we
actually need to cut back on them. Omega-6 fatty acids are found in most
vegetable oils, soybean oil, corn oil, sunflower oil, and peanut oil. Some
experts believe that we currently consume about 14 times more omega-6 than omega-3
fatty acids. The goal is to bring this consumption closer to an equal intake or,
at most, only 3 grams of omega-6 fatty acids for every 1 gram of omega-3 fatty
acids. Flaxseed oil and flaxseeds are the only source of ALA that does not also
provide omega-6 fatty acids.
While there are no official guidelines for how to get an adequate amount of
omega-3 fatty acids in a vegetarian diet, there are some recommendations that
you can follow:
- Use microalgae oil as a replacement for fatty fish consumption.
- Use flaxseed oil or flaxseeds (ground or crushed) as your source of ALA. Do
not heat the oil when you use it. - Cut back on your intake of omega-6 fatty
acids by replacing plant oils with olive oil or rapeseed oil.
QUESTION
According to the USDA, there is no difference between a “portion” and a “serving.”
See Answer
Vitamin B12
Vitamin B12 is attached to the protein in animal foods. There has been
considerable research to determine if it is also found in some plant foods.
Unfortunately, the B12 that has been found in plant foods can’t be used by
humans. Supplements that have been made with the plant sources have been shown
to contain B12 analogues, compounds that are structurally similar to B12 but do
not serve the same function. Research has shown that using supplements with
these analogues can actually compete with vitamin B12, inhibit its metabolism,
and increase the risk of B12 deficiency.
Vitamin B12 deficiency causes a number of symptoms and problems, including weakness, tiredness, constipation, loss of appetite, weight loss, poor memory, dementia, depression, problems with balance, and megaloblastic anemia. You may also experience nerve problems, such as numbness and tingling in the hands and feet. Vitamin B12 deficiency can damage the nervous system even in people who don’t have anemia, so it is important to treat a deficiency as soon as possible.
Vitamin B12 is found in seafood, dairy, eggs, and meat. Vegan diets have the
highest risk of deficiency. There are many foods that are fortified with vitamin
B12, so it is possible for vegan diets to contain adequate amounts of this
nutrient with or without a supplement. The recommendations for reaching your
vitamin B12 needs are to
- consume food fortified with vitamin B12 two to three times a day,
- take a
B12 supplement if you are unable to consume an adequate amount in your diet or
if you have an increased need for it (the elderly and pregnant and lactating women), - do not take excessive amounts of folate supplements, as this can mask a B12
deficiency, - have your B12 level checked by your physician.
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Calcium
The most well-known source of calcium is dairy foods, which are often
omitted or greatly limited in vegetarian diets and are completely omitted in
vegan diets. Dairy products provide 70% of the dietary calcium of the U.S.
population. The nondairy foods that provide calcium are calcium-fortified tofu,
some roots and legumes, and fortified soy milk.
Certain factors will impact how
much calcium you actually absorb from the food, such as the amount of calcium
that is present and the presence of vitamin D. The presence of vitamin D will
enhance absorption, while the presence of oxalic acid and phytic acid will
interfere with the absorption. Foods rich in oxalic acid are spinach, rhubarb,
sweet potatoes, and beans. Foods rich in phytic acid are unleavened bread, nuts,
seeds, and raw beans. You will absorb some of the calcium in foods that you
consume when oxalic acid and phytic acids are present but not as much as you
would when they are not present. For example, calcium absorption from dried
beans is about half of that absorbed from milk, and calcium absorption from
spinach is about one-tenth of that from milk.
The following are recommendations for consuming an adequate amount of
calcium:
- Consume two servings of dairy products per day, with 200 mg coming from other
food sources. - Vegans should consume calcium-fortified
juices or soy milk on a daily basis, calcium-rich foods throughout the day, and
consider taking a daily supplement. - Calcium intake needs to be spread
throughout the day for optimal absorption. We do not efficiently absorb more
than 500 mg at a time, so there is no need to try to consume high amounts all at
once.
Vitamin D
Vitamin D deficiency has become a worldwide epidemic. People who exclude fish and dairy from their diet can be even more susceptible to a vitamin D deficiency. There are numerous benefits to vitamin D, including decreased incidence and severity of cardiovascular disease, lowering of blood pressure in hypertension, prevention and treatment of depression, decreased risk of type 2 diabetes, prevention of osteoporosis and osteopenia, decreased inflammation, decreased dental cavities, reduced risk of
allergies in children and adolescents, decreased mortality from various forms of cancer, decreased incidence of rickets, possible decrease in erectile dysfunction, and regulation of blood cholesterol.
The only way to know for sure if you are getting enough vitamin D is to have your blood tested. It is a good idea for people following a vegetarian diet to do this, especially children. Exposing your skin to the sun for 10 to 15 minutes, without sunscreen, a couple of times per week is an option for some to meet their vitamin D needs. When this is not an option, research shows that supplementation can be effective in preventing this deficiency.
Iron
Iron is essential for health and transporting oxygen. A deficiency in iron
causes fatigue and decreased immune function. There are two forms of dietary
iron: heme and nonheme. Heme iron is found in animal foods, while nonheme iron
is in plant foods.
The amount of iron that the body obtains and uses from the food is referred to as iron absorption. The iron absorption from heme iron ranges from 15%-35% while the absorption from nonheme iron is only 2%-20%. Evidence does not show any greater iron deficiency anemia in vegetarians than in omnivores, but body iron stores in vegetarians do tend to be lower so it’s important to pay attention to your intake. There are ways to increase the absorption of nonheme iron and meet your recommendations:
- Consuming vitamin C (citrus fruits, juice, red peppers) at the same time
that you consume foods with nonheme iron will increase iron absorption. - Consuming meat protein at the same time that you consume nonheme iron foods
increases iron absorption. - Calcium, tannins, and phytates interfere with the
absorption of iron. Tannins are found in tea and coffee. Phytates are found in
whole grains and legumes. Take any supplements containing calcium and foods
containing calcium, tannins, or phytates separately from the time you consume
iron-rich foods or an iron supplement. - When you need a supplement, you want one
with ferrous iron salts (ferrous fumarate, ferrous sulfate, and ferrous
gluconate). The amount of iron that you absorb decreases with increasing doses,
so it’s best to spread your supplements out over the day. Iron can be toxic at
high levels, so do not supplement if you do not need to and consult with your
physician before taking a supplement. - Have your iron levels checked by your
physician.
Producing and maintaining new cells; helps make DNA; helps maintain
the nervous system
- Mollusks, clams
- Beef liver
- Trout
- Salmon
- Beef
- Yogurt
- Haddock
- Tuna
- Milk
- Eggs
Fortified foods:
- Breakfast cereals
- Vegetable stock
- Vegetable and sunflower
margarines - Veggie burgers
- Textured vegetable protein
- Yeast extracts
- Soy milk
Strong bones; contract and expand blood vessels and muscles; send
message to nervous system; secrete hormones and enzyme
- Milk
- Cheese
- Cottage cheese
- Salmon w/bones
- Sardines w/bones
- Yogurt
- Fortified soy milk
- Fortified juice
- Tofu-made w/calcium sulfate
- Soybeans
- Soy nuts
- Bok choy
- Kale
- Mustard greens
- Blackstrap molasses
Transport oxygen; regulation of cell growth and
differentiation; integral part of many proteins and enzymes
Heme iron:
- Chicken liver
- Oysters
- Beef
- Clams
- Turkey
- Chicken
- Tuna
Non-heme iron:
- Chickpeas
- Lentils
- Beans
- Fortified cereal
- Fortified
oatmeal - Tofu
- Wheat
Decreased incidence and severity of cardiovascular disease; lowering of
blood pressure in hypertension; prevention and treatment of depression;
decreased risk of type 2 diabetes; prevention of osteoporosis and
osteopenia; decreased inflammation; decreased dental cavities; reduced risk
of allergies in children and adolescents; decreased mortality from various
forms of cancer; decreased incidence of rickets; possible decrease in
erectile dysfunction; and regulation of blood cholesterol
- Sunlight
- Cod liver oil
- Salmon
- Sardines
- Mackerel
- Tuna
- Egg yolk
- Fortified milk
- Sunlight
- Shiitake mushrooms
- Fortified orange juice
- Supplements
Protect against atherosclerosis; reduce triglyceride levels; act as
an anti-inflammatory; possibly help with depression and other
personality disorders; and possibly thin the blood
Fatty fish:
- Anchovies
- Bluefish
- Carp
- Catfish
- Halibut
- Herring
- Lake
trout - Mackerel
- Pompano
- Salmon
- Striped sea bass
- Whitefish
- White tuna (Albacore)
Source EPA & DHA:
Microalgae oil
Source EPA:
- Flaxseed oil
- Flaxseeds
- Rapeseed
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What are the benefits of the various kinds of vegetarian and vegan diets?
The health benefits of a vegetarian diet are the number-one reason why people
choose to follow this way of eating. The Dietary Guidelines for Americans
support the benefit of a vegetarian diet: "Most Americans of all ages eat fewer
than the recommended number of servings of grain products, vegetables, and
fruits, even though consumption of these foods is associated with a
substantially lower risk for many chronic diseases, including certain types of
cancer." Large-scale studies including the Adventist Health Study, the Oxford Vegetarian Study, the Health Food Shoppers study, and the Heidelberg Study have shown that overall, vegetarians tend to be slimmer, appear to be in better health, and have a reduced risk of chronic diseases and greater longevity when compared with omnivores.
Some of the other health benefits attributed to following a vegetarian diet are at a lower risk for cardiovascular disease, hypertension, type 2 diabetes,
diverticulosis, renal disease, some cancers (including lung and breast), and
gallstones. The reason for these health benefits comes from the foods that are reduced or omitted as well as from the foods that are consumed. A healthy lifestyle that includes physical activity and a low consumption of alcohol and tobacco may also play a role in acquiring these benefits.
The similarities in the various kinds of vegetarian diets are the high consumption of fruit, vegetables, soy, nuts, and legumes. Overall, they tend to have a lower intake of saturated fat and cholesterol and the higher intakes of complex carbohydrates,
dietary fiber, certain minerals, and phytochemicals. Cholesterol is only found
in animal foods, so vegan diets are completely cholesterol-free.
There is evidence linking red meat, especially processed meat, with an increased risk of cancer, coronary heart disease, and type 2 diabetes. Cutting back on the quantity and frequency of red meat consumption can lead to health benefits. Many believe that this is the biggest contributor to the health benefits that are found with the vegetarian diet.
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How do I develop a vegetarian or vegan diet plan for myself?
The first thing to decide is if you are going to consume any source of animal
foods. There really is no one “right” way to do this. You can have cheese but
no milk; or you may choose poultry but no beef. You want to make your diet plan
fit your lifestyle and include the foods that you enjoy consuming. You will get
some of the health benefits of a vegetarian diet even if you only consume one or
two vegetarian meals per week. In fact, starting out by slowly adding vegetarian
meals may make the transition easier if you are not used to this way of eating.
Here are some keys to balancing your meals.
Protein
Protein is an essential nutrient that is needed for growth, immune
function, and muscle mass. Protein is made up of amino acids. There are some
amino acids that our bodies can make and others that must be supplied from our
diet. Protein is the only nutrient that will increase your satiety; meaning that
you will stay full in between meals. This makes protein an integral part of any
weight loss plan.
The Institute of Medicine recommends that adults get a minimum of 0.8 grams
of protein per kg of body weight each day. To determine your need, use this
calculation:
- Your body weight in pounds divided by 2.2 = ________ your
body weight in kg - Your body weight in kg times 0.8 = ________ grams of
protein per day
Animal foods tend to be the highest source of protein in our diets and can
provide all the amino acids that we need, making it a complete protein. Every
ounce of an animal food provides 7 grams of protein and varying amounts of fat.
Seafood and poultry provide the lowest amount of fat per serving and therefore
the lowest number of calories per serving. If you are consuming any meat,
poultry, or seafood, you can use a deck of cards as a guideline for the amount
that you are consuming. A piece of meat that is the size of a deck of cards is
approximately 3 oz with 21 grams of protein. The amount that you eat will depend
on the amount of calories that you are allowed to consume and any other sources
of calories that you are consuming. You only need to use the deck of cards as a
guideline to determine what a 3 oz serving looks like. One egg and 1 ounce of
cheese (typically one slice) are considered one serving.
Plant foods also provide protein, along with fiber and some vitamins and minerals that you won’t find in animal foods. The one limitation to these is that they are not considered complete proteins because they do not provide all of the necessary amino acids. The exceptions to this are soybeans and quinoa, which are considered complete proteins. Beans, seeds, nuts, and grains are excellent sources of protein. The way to make them complete proteins is to combine them. A very popular dish that takes two incomplete proteins and makes a complete one is rice and beans.
In America, vegan diets are commonly lower in protein in comparison to the
standard American diet. But it is possible to consume a vegan diet and reach
your recommended amount of protein. Two to three servings of protein-rich foods
each day are usually enough to meet the daily needs of most adults. One serving
is considered to be ½ cup of cooked dried beans, 2 tablespoons of peanut butter, or 1
ounce of nuts.
The protein content of some common vegan foods is as follows:
2 tbsp
5 g
¼ cup
8 g
1 cup
15 g
1 cup
11 g
1 cup
4 g
1 cup
5 g
1 cup
6 g
¼ cup
5 g
1 cup
12 g
1 cup
13 g
1 cup
18 g
1 cup
10 g
2 tbsp
8 g
1 cup
9 g
1 cup
12 g
1 cup
9 g
3 oz
31 g
1 cup
7 g
6 oz
6 g
1 cup
29 g
1 cup
5 g
¼ cup
6 g
1 cup
41 g
4 oz
11 g
4 oz
9 g
Two slices
5 g
You may not be familiar with all of these foods if you are just starting out.
Take some time to do some research and experiment with recipes. Here is some
information about three of the most popular sources of protein.
Tofu: Tofu is made by treating soybean milk with coagulants. It is also known
as soybean curd and resembles cheese. It has a high protein content so it can be
used as the “meat” source for a meal. Tofu itself is bland, but it absorbs
flavors very well, so it’s best prepared with flavorful spices or marinades.
There are soft, firm, and extra firm varieties. The soft tofu is smoother and
lower in fat and is best used in sauces, salad dressings, and desserts. The firm
and extra firm tofu are best used in grilling, baking, and stir-frying.
Tempeh: Tempeh (pronounced TEM-pay or tem-pā) is made by fermenting soybeans
with a rhizopus. It can be made of all soy or combined with grains, seeds, and
legumes. It has a nutty taste and a firm, tender, and chewy texture. Tempeh’s
high protein content makes it an excellent substitute for meat. High-quality tempeh slices or cubes easily without crumbling. Look for tempeh that is covered
with a thin whitish bloom. While it may have a few black or grayish spots, it
should have no evidence of pink, yellow, or blue coloration as this indicates
that it has become overly fermented. Like tofu, it absorbs the flavors of spices
and marinades.
Quinoa: Quinoa (pronounced KEEN-wah) is a seed that is related to leafy green
vegetables. It’s often used as a grain, but unlike grains, it is considered a
complete protein source. This means that it can also replace meat as a source of
protein in your meal. It also provides fiber, iron, magnesium, phosphorus, and
is gluten-free. It needs to be rinsed before cooking to remove the bitter
coating substance that protects it from birds and insects. You can buy products
that have already had this removed. Many people recommend that you presoak
quinoa for 15 to 30 minutes to bring out the nutty flavor and remove the bitter
flavor. To do this, you take 1 ½ cups of cold water and add 1 cup of quinoa to
it and allow it to soak and then drain the water off. When you don’t have time
to soak it, you can use hot water and soak it for five minutes and then rinse a
couple of times. You cook it in water that can either be two or three parts
water for one part quinoa. The seeds swell to about two to four times their
original size. Bring it to a boil, cover, and turn the heat down to simmer and
cook for 20 minutes. When you remove it from the heat, allow it to sit with the
cover on for five minutes and then fluff with a fork. You will see the seeds are a
bit transparent and display a little white thread that curls around them. There
are lots of great recipes that you can use this with, so experiment and enjoy!
Balance
The goal for any diet is to consume a balance of foods that provide
your body with all of the nutrients that it needs to function optimally. The
Food Guide Pyramid was developed to show the amount and type of foods to
consume. A serving is a standard measurement, not the amount that you actually
consume, which is called a portion. For example, one serving of bread is one slice,
and your portion may be two slices, which means that you had two servings. If you
want the health benefits of a vegetarian diet, you need to consume the foods that
will provide these benefits. This means lots of vegetables, fruits, whole grains,
lean sources of protein, and healthy fats. You can use the Food Guide Pyramid as
a guideline for balancing your diet.
What are resources for vegetarian and vegan recipes?
Vegan
http://www.vegfamily.com/vegan-recipes/
Vegetarian
http://www.vegweb.com/
http://www.vrg.org/recipes/
http://www.vegetariantimes.com/recipes/
http://www.recipezaar.com/recipes/egetarian
What is included in the vegetarian food pyramid?
Vegetarian Food Pyramid
What is included in the vegan food pyramid?
Vegan Food Guide Pyramid
It’s important to remember that you can consume too many calories following a
vegetarian or a vegan diet. Too much of any food can lead to weight gain and the
health problems associated with being overweight. Part of consuming a balanced
diet means moderation. You also want to include water and physical activity in
your plan. This is about making a healthy lifestyle change and making choices
that “feed” your body and mind in the right way.
Where can I get more information on vegetarian and vegan diets during pregnancy?
Vegetarian diets for pregnancy: http://www.pcrm.org/search/?cid=262
Pregnancy and a vegan diet: http://www.vrg.org/nutrition/veganpregnancy.php
Where can I get more information on vegetarian and vegan diets?
Books and magazines
125 Gluten-Free Vegetarian Recipes: Quick and Delicious Mouthwatering Dishes for the Healthy Cook by Carol Fenster, Ph.D. Penguin Publishing, 2011.
Becoming Vegan: The Complete Guide to Adopting a Healthy Plant-Based Diet by Brenda Davis, RD, and Vesanto Melina., MS, RD. Summertown, TN: Book Publishing Company, 2000.
Being Vegetarian for Dummies by Suzanne Havala, MS, RD. Cleveland, OH: IDG Books Worldwide, 2001.
New Becoming Vegetarian: The Essential Guide to a Healthy Vegetarian Diet by Vesanto Melina., MS, RD, and Brenda Davis, RD. Summertown, TN: Book Publishing Company, 2003.
Practically Raw: Flexible Raw Recipes Anyone Can Make by Amber Shea Crawley. Vegan Heritage Press, 2012.
Simply Vegan: Quick Vegetarian Meals, 4th ed. by Debra Wasserman; Nutrition Section by Reed Mangels, Ph.D., RD. Baltimore, MD: The Vegetarian Resource Group, 2006.
The Happy Herbivore Cookbook: Over 175 Delicious Fat-Free and Low-Fat Vegan Recipes by Lindsay S. Nixon. BenBella Books, 2011.
The Flexitarian Diet: The Mostly Vegetarian Way to Lose Weight, Be Healthier, Prevent Disease, and Add Years to Your Life by Dawn Jackson Blatner, RD, LDN. McGraw-Hill, 2008.
Vegan & Vegetarian FAQ: Answers to Your Frequently Asked Questions by Davida Gypsy Breier; Nutrition Section by Reed Mangels, Ph.D., RD. Baltimore, MD: The Vegetarian Resource Group, 2001.
Vegetarian Times: http://www.vegetariantimes.com/
Veg News: http://www.vegnews.com/web/home.do
Web sites
American Vegan Society: http://www.americanvegan.org/
North American Vegetarian Society: http://www.navs-online.org/
Vegan Action: http://www.vegan.org/
Vegan Outreach: https://www.mosaicfoods.com/pages/vegan-diet-beginners-guide
IIn a Vegetarian Kitchen: http://vegkitchen.com/
The Vegetarian Resource Group: http://www.vrg.org/
Food and Nutrition Information Center: http://www.choosemyplate.gov/food-groups/downloads/VegetarianNutritionResourceList.pdf