Introduction to vegetarian diets
To eat meat, or not to eat meat…This is the question on many people’s mind. 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 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?
| Type of vegetarian diet | Foods that you do consume | Foods that are not consumed |
| Vegan | Only plant-based foods | Meat Poultry Fish Milk Eggs Cheese Honey *Also avoid: leather, fur, silk, wool, soaps and cosmetics derived from animal product |
| Lacto-vegetarian | Plant-based foods Milk Milk products
|
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| Lacto-ovo vegetarian | Plant-based foods Milk Milk products
Eggs |
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| Flexitarian (semi-vegetarian) | Plant-based foods Occasionally consume or consume in limited quantity any or all of the following:
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Animals foods consumed in limited quantity and/or frequency |
What are the potential health problems from consuming a vegetarian and vegan diet?
Many people believe that it’s not possible to consume all of your necessary nutrients without meat in your diet. 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 antiinflammatory 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 non-meat 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 state 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.
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, a very serious condition that can lead to anemia and irreversible nerve damage.
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
1. consume food fortified with vitamin B12 two to three times a day,
2. 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 (elderly, pregnant, and lactating women),
3. do not take excessive amounts of folate supplements, as this can mask a B12 deficiency, and
4. have your B12 level checked by your physician.
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:
1. Consume two servings of dairy products per day, with 200 mg coming from other food sources.
2. 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.
3. 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.
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%. 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.
| Nutrient | Function | Non-Vegan Sources | Vegan Sources |
| Vitamin B12 | Producing and maintaining new cells; helps make DNA; helps maintain the nervous system |
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Fortified foods:
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| Calcium | Strong bones; contract and expand blood vessels and muscles; send message to nervous system; secrete hormones and enzyme |
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| Iron | Transport oxygen; regulation of cell growth and differentiation; integral part of many proteins and enzymes | Heme iron:
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Non-heme iron:
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| Omega-3 Fatty Acids | Protect against atherosclerosis; reduce triglyceride levels; act as an antiinflammatory; possibly help with depression and other personality disorders; and possibly thin the blood | Fatty fish:
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Source EPA & DHA: Microalgae oil Source EPA: |
What are the benefits of a vegetarian and vegan diet?
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.” Research has shown that people who follow a vegetarian diet are at a lower risk for obesity, cardiovascular disease, hypertension, type 2 diabetes, diverticulosis, renal disease, some cancers (including lung and breast), and gallstones. Vegetarian diets have also been shown to benefit people who already have type 2 diabetes. In one study, 43% of the people with type 2 diabetes who ate a low-fat vegan diet reduced their need for diabetes medications.
The reason for these health benefits comes from the lower intakes 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.
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:
1. Your body weight in pounds divided by 2.2 = ________ your body weight in kg
2. 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 one exception to this is 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:
| Food | Amount | Protein |
| Almond butter | 2 tbsp | 5 g |
| Almonds | ¼ cup | 8 g |
| Black beans, cooked | 1 cup | 15 g |
| Black-eyed peas, cooked | 1 cup | 11 g |
| Broccoli, cooked | 1 cup | 4 g |
| Brown rice, cooked | 1 cup | 5 g |
| Bulgar, cooked | 1 cup | 6 g |
| Cashews | ¼ cup | 5 g |
| Chickpeas, cooked | 1 cup | 12 g |
| Kidney beans, cooked | 1 cup | 13 g |
| Lentils, cooked | 1 cup | 18 g |
| Lima beans, cooked | 1 cup | 10 g |
| Peanut butter | 2 tbsp | 8 g |
| Peas, cooked | 1 cup | 9 g |
| Pinto beans, cooked | 1 cup | 12 g |
| Quinoa, cooked | 1 cup | 9 g |
| Seitan | 3 oz | 31 g |
| Soy milk | 1 cup | 7 g |
| Soy yogurt, plain | 6 oz | 6 g |
| Soybeans, cooked | 1 cup | 29 g |
| Spinach, cooked | 1 cup | 5 g |
| Sunflower seeds | ¼ cup | 6 g |
| Tempeh | 1 cup | 41 g |
| Tofu, firm | 4 oz | 11 g |
| Tofu, regular | 4 oz | 9 g |
| Whole wheat bread | Two slices | 5 g |
to be continue….
source: http://www.medicinenet.com/vegetarian_and_vegan_diet/article.htm