Vegetarian nutrition - AbsoluteAstronomy.com

Vegetarian nutrition is the set of health-related challenges and advantages of vegetarian

Vegetarianism

Vegetarianism encompasses the practice of following plant-based diets , with or without the inclusion of dairy products or eggs, and with the exclusion of meat...

diets.

Well-planned vegetarian and vegan diets are nutrition

Nutrition

Nutrition is the provision, to cells and organisms, of the materials necessary to support life. Many common health problems can be prevented or alleviated with a healthy diet....

ally adequate and are appropriate for all stages of the life cycle, including during pregnancy, lactation, infancy, childhood, and adolescence. A vegetarian diet can provide adequate protein

Protein

Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...

, iron

Iron

Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...

, zinc

Zinc

Zinc , or spelter , is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table. Zinc is, in some respects, chemically similar to magnesium, because its ion is of similar size and its only common oxidation state is +2...

, vitamin B₁₂

Vitamin B12

Vitamin B12, vitamin B12 or vitamin B-12, also called cobalamin, is a water-soluble vitamin with a key role in the normal functioning of the brain and nervous system, and for the formation of blood. It is one of the eight B vitamins...

, and calcium

Calcium

Calcium is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft gray alkaline earth metal, and is the fifth-most-abundant element by mass in the Earth's crust...

intake, though these nutrients can be relatively low in poorly planned vegetarian diets, particularly when not enough calories are consumed.

Evidence suggests that vegetarians have lower rates of coronary heart disease

Coronary heart disease

Coronary artery disease is the end result of the accumulation of atheromatous plaques within the walls of the coronary arteries that supply the myocardium with oxygen and nutrients. It is sometimes also called coronary heart disease...

, obesity

Obesity

Obesity is a medical condition in which excess body fat has accumulated to the extent that it may have an adverse effect on health, leading to reduced life expectancy and/or increased health problems...

, hypertension

Hypertension

Hypertension or high blood pressure is a cardiac chronic medical condition in which the systemic arterial blood pressure is elevated. What that means is that the heart is having to work harder than it should to pump the blood around the body. Blood pressure involves two measurements, systolic and...

, type 2 diabetes

Diabetes mellitus type 2

Diabetes mellitus type 2formerly non-insulin-dependent diabetes mellitus or adult-onset diabetesis a metabolic disorder that is characterized by high blood glucose in the context of insulin resistance and relative insulin deficiency. Diabetes is often initially managed by increasing exercise and...

, osteoporosis

Osteoporosis

Osteoporosis is a disease of bones that leads to an increased risk of fracture. In osteoporosis the bone mineral density is reduced, bone microarchitecture is deteriorating, and the amount and variety of proteins in bone is altered...

, and dementia

Dementia

Dementia is a serious loss of cognitive ability in a previously unimpaired person, beyond what might be expected from normal aging...

. Vegetarian diets tend to be rich in carbohydrates, omega-6 fatty acids, dietary fibre, carotenoids, folic acid

Folic acid

Folic acid and folate , as well as pteroyl-L-glutamic acid, pteroyl-L-glutamate, and pteroylmonoglutamic acid are forms of the water-soluble vitamin B9...

, vitamin C

Vitamin C

Vitamin C or L-ascorbic acid or L-ascorbate is an essential nutrient for humans and certain other animal species. In living organisms ascorbate acts as an antioxidant by protecting the body against oxidative stress...

, vitamin E

Vitamin E

Vitamin E is used to refer to a group of fat-soluble compounds that include both tocopherols and tocotrienols. There are many different forms of vitamin E, of which γ-tocopherol is the most common in the North American diet. γ-Tocopherol can be found in corn oil, soybean oil, margarine and dressings...

, potassium

Potassium

Potassium is the chemical element with the symbol K and atomic number 19. Elemental potassium is a soft silvery-white alkali metal that oxidizes rapidly in air and is very reactive with water, generating sufficient heat to ignite the hydrogen emitted in the reaction.Potassium and sodium are...

and magnesium

Magnesium

Magnesium is a chemical element with the symbol Mg, atomic number 12, and common oxidation number +2. It is an alkaline earth metal and the eighth most abundant element in the Earth's crust and ninth in the known universe as a whole...

. They are generally low in saturated fat

Saturated fat

Saturated fat is fat that consists of triglycerides containing only saturated fatty acids. Saturated fatty acids have no double bonds between the individual carbon atoms of the fatty acid chain. That is, the chain of carbon atoms is fully "saturated" with hydrogen atoms...

, cholesterol

Cholesterol

Cholesterol is a complex isoprenoid. Specifically, it is a waxy steroid of fat that is produced in the liver or intestines. It is used to produce hormones and cell membranes and is transported in the blood plasma of all mammals. It is an essential structural component of mammalian cell membranes...

, and animal protein.

Benefits of a vegetarian diet

Vegetarian diets are usually rich in carbohydrates, omega-6 fatty acids, dietary fiber

Dietary fiber

Dietary fiber, dietary fibre, or sometimes roughage is the indigestible portion of plant foods having two main components:* soluble fiber that is readily fermented in the colon into gases and physiologically active byproducts, and* insoluble fiber that is metabolically inert, absorbing water as it...

, carotenoids, folic acid

Folic acid

Folic acid and folate , as well as pteroyl-L-glutamic acid, pteroyl-L-glutamate, and pteroylmonoglutamic acid are forms of the water-soluble vitamin B9...

, vitamin C

Vitamin C

, vitamin E

Vitamin E

, potassium

Potassium

and magnesium

Magnesium

. They usually contain lower levels of saturated fat

Saturated fat

, cholesterol

Cholesterol

, and animal protein.

The Oxford Vegetarian Study showed that the health of vegetarians compares favourably with that of meat-eaters (excluding pescetarians). British vegetarians have lower death rates

Mortality rate

Mortality rate is a measure of the number of deaths in a population, scaled to the size of that population, per unit time...

than non-vegetarians, although this is at least partly due to non-dietary lifestyle factors, such as a low prevalence of smoking and the generally high socioeconomic status

Socioeconomic status

Socioeconomic status is an economic and sociological combined total measure of a person's work experience and of an individual's or family’s economic and social position in relation to others, based on income, education, and occupation...

of vegetarians, or to aspects of the diet other than the avoidance of meat and fish.

Loma Linda University School of Public Health

Loma Linda University School of Public Health

The Loma Linda University School of Public Health offers degrees in environmental and occupational health, epidemiology and biostatistics, global health, health policy and management, health promotion and education, and nutrition.- History :...

has conducted three cohort studies that identify the health benefits of a vegetarian diet. The University is a Seventh-day Adventist

Seventh-day Adventist Church

The Seventh-day Adventist Church is a Protestant Christian denomination distinguished by its observance of Saturday, the original seventh day of the Judeo-Christian week, as the Sabbath, and by its emphasis on the imminent second coming of Jesus Christ...

health science institution. The first study, funded by the US Public Health Service in 1958 and limited to Adventists in California, included many vegetarians. The next cohort of California Adventists, the Adventist Health Study-1 (AHS-1), collected data from 1974 to 1976. From 2002 to 2007 the Adventist Health Study-2 (AHS-2) collected dietary data from 96,000 church members from the United States and Canada. Many scientific articles have been published on the health and nutrition properties of a vegetarian diet from these cohort studies. The most recent AHS-2 study includes findings on metabolic syndrome

Metabolic syndrome

Metabolic syndrome is a combination of medical disorders that, when occurring together, increase the risk of developing cardiovascular disease and diabetes. It affects one in five people in the United States and prevalence increases with age...

, Vitamin D

Vitamin D

Vitamin D is a group of fat-soluble secosteroids. In humans, vitamin D is unique both because it functions as a prohormone and because the body can synthesize it when sun exposure is adequate ....

absorption and type-2 diabetes

The 2010 version of Dietary Guidelines for Americans, a report issued by the U.S. Department of Agriculture and the U.S. Department of Health and Human Services every five years, states that
Vegetarians may avoid the negative health effects of red meat: A 1999 meta-study

Meta-analysis

In statistics, a meta-analysis combines the results of several studies that address a set of related research hypotheses. In its simplest form, this is normally by identification of a common measure of effect size, for which a weighted average might be the output of a meta-analyses. Here the...

of five studies comparing vegetarian and non-vegetarian mortality rate

Mortality rate

Mortality rate is a measure of the number of deaths in a population, scaled to the size of that population, per unit time...

s in Western countries found that in comparison with regular meat eaters, mortality from ischemic heart disease was 34% lower in people who ate fish but not meat (pescetarians), 34% lower in ovo-lacto vegetarians, 26% lower in vegans and 20% lower in occasional meat eaters.

Doctors Dean Ornish

Dean Ornish

Dean Michael Ornish, M.D., is president and founder of the nonprofit Preventive Medicine Research Institute in Sausalito, California, as well as Clinical Professor of Medicine at the University of California, San Francisco....

, T. Colin Campbell

T. Colin Campbell

T. Colin Campbell is an American biochemist who specializes in the effects of nutrition on long-term health. He is the Jacob Gould Schurman Professor Emeritus of Nutritional Biochemistry at Cornell University, and the author of over 300 research papers...

, John A. McDougall

John A. McDougall

John A. McDougall, M.D., is an American physician and author whose philosophy is that degenerative disease can be prevented and treated with a plant-based diet of whole, unprocessed, low-fat foods, especially starches such as potatoes, rice, and beans, and which excludes all animal foods and added...

, Caldwell Esselstyn

Caldwell Esselstyn

Caldwell Blakeman Esselstyn Jr., M.D., is an American physician, author, and former Olympic rowing champion.-Biography:...

and Neal D. Barnard

Neal D. Barnard

Neal D. Barnard is an American physician, author, clinical researcher, and founding president of the Physicians Committee for Responsible Medicine , an international network of physicians, scientists, and laypeople who promote preventive medicine, conduct clinical research, and promote higher...

claim that high animal fat and protein diets, such as the standard American diet, are detrimental to health. They also state that a lifestyle change incorporating a low fat vegetarian or vegan diet could not only prevent various degenerative diseases, such as coronary artery disease, but reverse them.

Studies of cancer have not shown clear differences in cancer rates between vegetarians and non-vegetarians. There is evidence that vegetarians tend to have a lower body mass index

Body mass index

The body mass index , or Quetelet index, is a heuristic proxy for human body fat based on an individual's weight and height. BMI does not actually measure the percentage of body fat. It was invented between 1830 and 1850 by the Belgian polymath Adolphe Quetelet during the course of developing...

, lower risk of obesity

Obesity

, lower blood cholesterol

Cholesterol

levels, lower homocysteine

Homocysteine

Homocysteine is a non-protein amino acid with the formula HSCH2CH2CHCO2H. It is a homologue of the amino acid cysteine, differing by an additional methylene group. It is biosynthesized from methionine by the removal of its terminal Cε methyl group...

levels, lower risk of high blood pressure

Hypertension

, and lower risk of type 2 diabetes

Diabetes mellitus type 2

. One large prospective study found that non-meat-eaters had only half the risk of meat eaters of requiring an emergency appendectomy.

Vegetarians are less likely to die by choking on food since the most common food to obstruct the airway is fish, which caused about 4,500 accidents a year in the UK as of 1998. Meat, poultry and bones were cited as the next three most common causes of choking, followed by sweets and non-food objects.

Potential nutrient deficiencies

Poorly planned vegetarian diets may be low in vitamin B₁₂

Vitamin B12

, calcium

Calcium

, omega-3 fatty acids, vitamin D

Vitamin D

Vitamin D is a group of fat-soluble secosteroids. In humans, vitamin D is unique both because it functions as a prohormone and because the body can synthesize it when sun exposure is adequate ....

, iron

Iron

, zinc

Zinc

, riboflavin

Riboflavin

Riboflavin, also known as vitamin B2 or additive E101, is an easily absorbed micronutrient with a key role in maintaining health in humans and animals. It is the central component of the cofactors FAD and FMN, and is therefore required by all flavoproteins. As such, vitamin B2 is required for a...

(vitamin B₂), and iodine

Iodine

Iodine is a chemical element with the symbol I and atomic number 53. The name is pronounced , , or . The name is from the , meaning violet or purple, due to the color of elemental iodine vapor....

, and poorly planned vegan diets may have particularly low intakes of vitamin B₁₂ and calcium. Nonetheless, well-balanced vegetarian and vegan diets can meet all these nutrient requirements and are appropriate for all stages of the life cycle, including during pregnancy

Pregnancy

Pregnancy refers to the fertilization and development of one or more offspring, known as a fetus or embryo, in a woman's uterus. In a pregnancy, there can be multiple gestations, as in the case of twins or triplets...

, lactation

Lactation

Lactation describes the secretion of milk from the mammary glands and the period of time that a mother lactates to feed her young. The process occurs in all female mammals, however it predates mammals. In humans the process of feeding milk is called breastfeeding or nursing...

, infancy

Infant

A newborn or baby is the very young offspring of a human or other mammal. A newborn is an infant who is within hours, days, or up to a few weeks from birth. In medical contexts, newborn or neonate refers to an infant in the first 28 days after birth...

, childhood

Childhood

Childhood is the age span ranging from birth to adolescence. In developmental psychology, childhood is divided up into the developmental stages of toddlerhood , early childhood , middle childhood , and adolescence .- Age ranges of childhood :The term childhood is non-specific and can imply a...

, and adolescence

Adolescence

Adolescence is a transitional stage of physical and mental human development generally occurring between puberty and legal adulthood , but largely characterized as beginning and ending with the teenage stage...

. Many tools are available to help vegetarians maintain an adequate nutrient balance including several Vegetarian Diet Pyramid

Vegetarian Diet Pyramid

Vegetarian Diet Pyramid is a nutrition guide that represents a traditional healthy vegetarian diet. Variations of this traditional healthy vegetarian diet exist throughout the world, particularly in parts of North America, Europe, South America, and most notably, Asia...

Protein

The typical vegetarian gets adequate protein

Protein in nutrition

Proteins are polymer chains made of amino acids linked together by peptide bonds. Proteins and carbohydrates contain 4 kcal per gram as opposed to lipids which contain 9 kcal per gram....

as long as caloric intake is adequate and a variety of foods is eaten.
Vegetarian diets tend to be lower in protein than non-vegetarian diets but typically meet or exceed daily protein intake recommendations, which is believed to be beneficial. Plant sources of protein include soy beans (and soy products such as tofu

Tofu

is a food made by coagulating soy milk and then pressing the resulting curds into soft white blocks. It is part of East Asian and Southeast Asian cuisine such as Chinese, Japanese, Korean, Indonesian, Vietnamese, and others. There are many different varieties of tofu, including fresh tofu and tofu...

, veggie burgers, soy milk

Soy milk

Soy milk and sometimes referred to as soy drink/beverage is a beverage made from soybeans. A stable emulsion of oil, water, and protein, it is produced by soaking dry soybeans and grinding them with water...

, etc.), other legumes, nuts

Nut (fruit)

A nut is a hard-shelled fruit of some plants having an indehiscent seed. While a wide variety of dried seeds and fruits are called nuts in English, only a certain number of them are considered by biologists to be true nuts...

and seed

Seed

A seed is a small embryonic plant enclosed in a covering called the seed coat, usually with some stored food. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant...

s, and grains

Cereal

Cereals are grasses cultivated for the edible components of their grain , composed of the endosperm, germ, and bran...

Combining proteins

Despite a widespread belief that vegetarians must eat grains and beans within a few hours of each other in order to make a 'complete' protein which contains all 9 "essential amino acid

Essential amino acid

An essential amino acid or indispensable amino acid is an amino acid that cannot be synthesized de novo by the organism , and therefore must be supplied in the diet.-Essentiality vs. conditional essentiality in humans:...

s", this has never been substantiated by research. The protein-combining theory was brought to popular attention in Frances Moore Lappé

Frances Moore Lappé

Frances Moore Lappé is the author of 18 books including the three-million copy Diet for a Small Planet. She is the co-founder of three national organizations that explore the roots of hunger, poverty and environmental crises, as well as solutions now emerging worldwide through what she calls...

's 1971 bestseller Diet for a Small Planet
Diet for a Small Planet
Diet for a Small Planet is a 1971 bestselling book by Frances Moore Lappé, the first major book to critique grain-fed meat production as wasteful and a contributor to global food scarcity...

. In later editions of the book, as early as 1981, Lappé withdrew her contention that protein 'combining' is necessary.

Iron

In several studies, vegans and other vegetarians

Vegetarianism

Vegetarianism encompasses the practice of following plant-based diets , with or without the inclusion of dairy products or eggs, and with the exclusion of meat...

were not found to suffer from iron

Iron

-deficiency more than non-vegetarians. However, while one study agreed that iron-deficiency anemia

Anemia

Anemia is a decrease in number of red blood cells or less than the normal quantity of hemoglobin in the blood. However, it can include decreased oxygen-binding ability of each hemoglobin molecule due to deformity or lack in numerical development as in some other types of hemoglobin...

is not more common among vegetarians, they found "vegetarian children had ... reduced levels of haemoglobin and iron compared to omnivores" due "to the absence of animal iron sources with high utilizability". Another study, in India, found that "strict vegetarian mothers as well as their newborns have a greater incidence and risk of anemia and iron deficiency."

The recommended iron intake for vegetarians is 1.8 times that of nonvegetarians, due to the fact that plant

Plant

Plants are living organisms belonging to the kingdom Plantae. Precise definitions of the kingdom vary, but as the term is used here, plants include familiar organisms such as trees, flowers, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The group is also called green plants or...

s, dairy, and eggs contain only non-heme iron, and this is absorbed less efficiently than heme iron. Although a lower percentage of non-heme iron is absorbed, greater amounts of non-heme iron are concentrated in many non-meat sources of iron (than the amount of iron per serving in meats), and therefore, cereals, eggs, nuts, seeds, and legumes (including soy foods, peas, beans, chickpeas, and lentils) are significant sources of iron, and a well-planned vegetarian diet should not lead to iron deficiency, but fruitarianism and raw foods diets should not be pursued for infants or children. Meat, fish, and poultry (not dairy or eggs) are the only sources of heme

Heme

A heme or haem is a prosthetic group that consists of an iron atom contained in the center of a large heterocyclic organic ring called a porphyrin. Not all porphyrins contain iron, but a substantial fraction of porphyrin-containing metalloproteins have heme as their prosthetic group; these are...

iron; intake of heme iron may be associated with colon cancer. Non-heme iron is more sensitive to both inhibitors and enhancers of iron absorption. Vitamin C

Vitamin C

is an iron absorption enhancer. The main inhibitors for most people are phytates (e.g. legumes and grains

Cereal

Cereals are grasses cultivated for the edible components of their grain , composed of the endosperm, germ, and bran...

), but other inhibitors include tannins (tea

Tea

Tea is an aromatic beverage prepared by adding cured leaves of the Camellia sinensis plant to hot water. The term also refers to the plant itself. After water, tea is the most widely consumed beverage in the world...

, wine

Wine

Wine is an alcoholic beverage, made of fermented fruit juice, usually from grapes. The natural chemical balance of grapes lets them ferment without the addition of sugars, acids, enzymes, or other nutrients. Grape wine is produced by fermenting crushed grapes using various types of yeast. Yeast...

), calcium

Calcium

and polyphenol

Polyphenol

Polyphenols are a structural class of natural, synthetic, and semisynthetic organic chemicals characterized by the presence of large multiples of phenol structural units...

s.

Iron

Iron

is an integral part of many protein

Protein

s and enzyme

Enzyme

Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...

s which maintain good health. In humans, iron is an essential component of proteins involved in red blood cell

Red blood cell

Red blood cells are the most common type of blood cell and the vertebrate organism's principal means of delivering oxygen to the body tissues via the blood flow through the circulatory system...

s' oxygen

Oxygen

Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...

transport. Iron also helps regulate cell growth

Cell growth

The term cell growth is used in the contexts of cell development and cell division . When used in the context of cell division, it refers to growth of cell populations, where one cell grows and divides to produce two "daughter cells"...

and differentiation

Cellular differentiation

In developmental biology, cellular differentiation is the process by which a less specialized cell becomes a more specialized cell type. Differentiation occurs numerous times during the development of a multicellular organism as the organism changes from a simple zygote to a complex system of...

Zinc

Western vegetarians and vegans have not been found to suffer from overt zinc

Zinc

deficiencies any more than meat-eaters. However, phytates in many whole-grains and fiber in many foods may interfere with zinc absorption and marginal zinc intake has poorly understood effects. Vegetarians may need more than the US RDA (15 mg) of zinc daily if their diet is high in phytates.

Major plant sources of zinc include cooked dried beans, sea vegetables, fortified cereals, soyfoods, nuts, peas, and seeds.

Vitamin B₁₂

Vitamin B12

deficiency is potentially extremely serious, leading to megaloblastic anemia

Megaloblastic anemia

Megaloblastic anemia is an anemia that results from inhibition of DNA synthesis in red blood cell production. When DNA synthesis is impaired, the cell cycle cannot progress from the G2 growth stage to the mitosis stage...

, nerve degeneration and irreversible neurological damage.

Lacto-ovo vegetarians may get vitamin B₁₂ from eggs and dairy products; for some this is adequate but some may remain B₁₂-deficient. The world's largest group of professional dietitians says the form of vitamin B₁₂ sourced from animal-products is protein-bound and not as easily digested, especially as people age, and therefore recommends B₁₂ supplementation for everyone over the age of 50. Pregnant and lactating vegetarians (and breastfed infants if the mother's diet is not supplemented) should also use supplements, whether pills, injections, or B₁₂-fortified foods, if they don't get adequate B₁₂ from animal-products like eggs or dairy.

Evidence suggests that vegetarians and vegans who are not taking vitamin B₁₂ supplements do not consume sufficient servings of B₁₂ and often have abnormally low blood concentrations of vitamin B₁₂. This is because, unless fortified, plant foods do not contain reliable amounts of active vitamin B₁₂

Vitamin B12

.

It is essential, therefore, that vegetarians consume adequate amounts of dietary supplements or foods that have been fortified with B₁₂ (such as nutritional yeast

Nutritional yeast

Nutritional yeast is a deactivated yeast, usually Saccharomyces cerevisiae. The scientific work of Louis Pasteur made it possible to isolate yeast in pure culture form. Nutritional yeast is produced by culturing the yeast with a mixture of sugarcane and beet molasses for a period of 7 days and...

or other yeast extract

Yeast extract

Yeast extract is the common name for various forms of processed yeast products made by extracting the cell contents ; they are used as food additives or flavourings, or as nutrients for bacterial culture media. They are often used to create savory flavors and umami taste sensations. Monosodium...

s, vegetable stock

Stock (food)

Stock is a flavoured water preparation. It forms the basis of many dishes, particularly soups and sauces.- Preparation :Stock is made by simmering various ingredients in water, including some or all of the following...

, veggie burger

Veggie burger

A veggie burger is a hamburger-style patty that does not contain meat. The patty of a veggie burger may be made, for example, from vegetables, textured vegetable protein , legumes, nuts, dairy products, mushrooms, wheat, or eggs....

mixes, textured vegetable protein

Textured vegetable protein

Textured or texturized vegetable protein , also known as textured soy protein , soy meat, or soya meat is a meat analogue or meat extender made from defatted soy flour, a by-product of extracting soybean oil...

, soy milk

Soy milk

s, vegetable and sunflower margarine

Margarine

Margarine , as a generic term, can indicate any of a wide range of butter substitutes, typically composed of vegetable oils. In many parts of the world, the market share of margarine and spreads has overtaken that of butter...

s, and breakfast cereal

Breakfast cereal

A breakfast cereal is a food made from processed grains that is often, but not always, eaten with the first meal of the day. It is often eaten cold, usually mixed with milk , water, or yogurt, and sometimes fruit but sometimes eaten dry. Some cereals, such as oatmeal, may be served hot as porridge...

s). B₁₂ that is to be used in these supplements is typically grown from vegan sources (such as bacteria). Another bacterial source happens to be that plants and edible fungi (like mushrooms) on farms or in the wild may absorb vitamin B₁₂ from bacteria in soil, but since modern pesticides kill most B₁₂ in the soil (including on organic farms to some degree, as the pesticides spread, via hydrology

Hydrology

Hydrology is the study of the movement, distribution, and quality of water on Earth and other planets, including the hydrologic cycle, water resources and environmental watershed sustainability...

, from non-organic farms to organic ones), the B₁₂ in these plants is not considered a reliable dietary source, whereas B₁₂ supplements from bacteria grown under controlled conditions are considered reliable amounts of B₁₂. There is a patent for a cultivating vitamin B₁₂ from plants.

Omega-3 fatty acids

Vegetarian diets can be low in omega-3 fatty acid

Omega-3 fatty acid

N−3 fatty acids are essential unsaturated fatty acids with a double bond starting after the third carbon atom from the end of the carbon chain....

s (O3FA). Major vegetarian sources of O3FA include algae

Algae

Algae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms, such as the giant kelps that grow to 65 meters in length. They are photosynthetic like plants, and "simple" because their tissues are not organized into the many...

, hempseeds and hempseed oil

Hemp

Hemp is mostly used as a name for low tetrahydrocannabinol strains of the plant Cannabis sativa, of fiber and/or oilseed varieties. In modern times, hemp has been used for industrial purposes including paper, textiles, biodegradable plastics, construction, health food and fuel with modest...

, walnut

Walnut

Juglans is a plant genus of the family Juglandaceae, the seeds of which are known as walnuts. They are deciduous trees, 10–40 meters tall , with pinnate leaves 200–900 millimetres long , with 5–25 leaflets; the shoots have chambered pith, a character shared with the wingnuts , but not the hickories...

s, flaxseeds and flaxseed oil

Flax

Flax is a member of the genus Linum in the family Linaceae. It is native to the region extending from the eastern Mediterranean to India and was probably first domesticated in the Fertile Crescent...

, olive oil

Olive oil

Olive oil is an oil obtained from the olive , a traditional tree crop of the Mediterranean Basin. It is commonly used in cooking, cosmetics, pharmaceuticals, and soaps and as a fuel for traditional oil lamps...

, canola

Canola

Canola refers to a cultivar of either Rapeseed or Field Mustard . Its seeds are used to produce edible oil suitable for consumption by humans and livestock. The oil is also suitable for use as biodiesel.Originally, Canola was bred naturally from rapeseed in Canada by Keith Downey and Baldur R...

(rapeseed

Rapeseed

Rapeseed , also known as rape, oilseed rape, rapa, rappi, rapaseed is a bright yellow flowering member of the family Brassicaceae...

) oil, avocado

Avocado

The avocado is a tree native to Central Mexico, classified in the flowering plant family Lauraceae along with cinnamon, camphor and bay laurel...

and chia seeds

Salvia hispanica

Salvia hispanica, commonly known as chia, is a species of flowering plant in the mint family, Lamiaceae, native to central and southern Mexico and Guatemala. The 16th century Codex Mendoza provides evidence that it was cultivated by the Aztec in pre-Columbian times; it has been said that it was an...

. However, diets lacking fish, eggs, or generous amounts of sea vegetables (seaweed) generally lack a direct source of long-chain O3FA such as eicosapentaenoic acid

Eicosapentaenoic acid

Eicosapentaenoic acid is an omega-3 fatty acid. In physiological literature, it is given the name 20:5. It also has the trivial name timnodonic acid...

(EPA) and docosahexaenoic acid

Docosahexaenoic acid

Docosahexaenoic acid is an omega-3 fatty acid that is a primary structural component of the human brain and retina. In chemical structure, DHA is a carboxylic acid with a 22-carbon chain and six cis double bonds; the first double bond is located at the third carbon from the omega end...

(DHA). Vegetarian diets may also have a high ratio of O6FA to O3FA, which inhibits the conversion of short-chain fatty acids such as alpha-Linolenic acid

Alpha-linolenic acid

α-Linolenic acid is an organic compound found in many common vegetable oils. In terms of its structure, it is named all-cis-9,12,15-octadecatrienoic acid. In physiological literature, it is given the name 18:3 ....

(ALA), found in most vegetarian O3FA sources, to EPA and DHA. Short-term supplemental ALA has been shown to increase EPA levels but not DHA levels, suggesting poor conversion of the intermediary EPA to DHA. DHA supplements derived from DHA-rich microalgae are available, and the human body can also convert DHA to EPA.

While there is no scientific consensus

Scientific consensus

Scientific consensus is the collective judgment, position, and opinion of the community of scientists in a particular field of study. Consensus implies general agreement, though not necessarily unanimity. Scientific consensus is not by itself a scientific argument, and it is not part of the...

on the role of omega-3 fatty acids, they may reduce the risk of coronary heart disease

Heart disease

Heart disease, cardiac disease or cardiopathy is an umbrella term for a variety of diseases affecting the heart. , it is the leading cause of death in the United States, England, Canada and Wales, accounting for 25.4% of the total deaths in the United States.-Types:-Coronary heart disease:Coronary...

, lower triglycerides, stabilize mood and help prevent depression

Clinical depression

Major depressive disorder is a mental disorder characterized by an all-encompassing low mood accompanied by low self-esteem, and by loss of interest or pleasure in normally enjoyable activities...

, help reduce symptoms of ADD

Attention-deficit hyperactivity disorder

Attention deficit hyperactivity disorder is a developmental disorder. It is primarily characterized by "the co-existence of attentional problems and hyperactivity, with each behavior occurring infrequently alone" and symptoms starting before seven years of age.ADHD is the most commonly studied and...

, reduce joint pain and other rheumatoid

Rheumatism

Rheumatism or rheumatic disorder is a non-specific term for medical problems affecting the joints and connective tissue. The study of, and therapeutic interventions in, such disorders is called rheumatology.-Terminology:...

problems, and reduce the risk of dementia

Dementia

Dementia is a serious loss of cognitive ability in a previously unimpaired person, beyond what might be expected from normal aging...

in older age. While there is little evidence of adverse health or cognitive effects due to DHA deficiency in adult vegetarians or vegans, fetal and breast milk levels remain a concern. EPA and DHA supplementation has been shown to reduce platelet aggregation in vegetarians, but a direct link to cardiovascular morbidity and mortality, which is already lower for vegetarians, has yet to be determined.

Vitamin D

The human body can synthesize

Biosynthesis

Biosynthesis is an enzyme-catalyzed process in cells of living organisms by which substrates are converted to more complex products. The biosynthesis process often consists of several enzymatic steps in which the product of one step is used as substrate in the following step...

vitamin D

Vitamin D

Vitamin D is a group of fat-soluble secosteroids. In humans, vitamin D is unique both because it functions as a prohormone and because the body can synthesize it when sun exposure is adequate ....

when skin

Skin

-Dermis:The dermis is the layer of skin beneath the epidermis that consists of connective tissue and cushions the body from stress and strain. The dermis is tightly connected to the epidermis by a basement membrane. It also harbors many Mechanoreceptors that provide the sense of touch and heat...

is exposed to ultraviolet radiation from the sun

Sun

The Sun is the star at the center of the Solar System. It is almost perfectly spherical and consists of hot plasma interwoven with magnetic fields...

. Vegans who do not eat foods or pills fortified with synthetic vitamin D and with little exposure to the sun's ultraviolet radiation (e.g., those who don't expose their extremities for at least 15–30 minutes per day or those living at latitude

Latitude

In geography, the latitude of a location on the Earth is the angular distance of that location south or north of the Equator. The latitude is an angle, and is usually measured in degrees . The equator has a latitude of 0°, the North pole has a latitude of 90° north , and the South pole has a...

s close to the pole

Geographical pole

A geographical pole is either of the two points—the north pole and the south pole—on the surface of a rotating planet where the axis of rotation meets the surface of the body...

s) are vulnerable to Vitamin D deficiencies.

Vitamin D acts as a hormone

Hormone

A hormone is a chemical released by a cell or a gland in one part of the body that sends out messages that affect cells in other parts of the organism. Only a small amount of hormone is required to alter cell metabolism. In essence, it is a chemical messenger that transports a signal from one...

, sending a message to the intestine

Intestine

In human anatomy, the intestine is the segment of the alimentary canal extending from the pyloric sphincter of the stomach to the anus and, in humans and other mammals, consists of two segments, the small intestine and the large intestine...

s to increase the absorption of calcium

Calcium

and phosphorus

Phosphorus

Phosphorus is the chemical element that has the symbol P and atomic number 15. A multivalent nonmetal of the nitrogen group, phosphorus as a mineral is almost always present in its maximally oxidized state, as inorganic phosphate rocks...

, which produces strong bone

Bone

Bones are rigid organs that constitute part of the endoskeleton of vertebrates. They support, and protect the various organs of the body, produce red and white blood cells and store minerals. Bone tissue is a type of dense connective tissue...

s. Vitamin D also works in concert with a number of other vitamin

Vitamin

A vitamin is an organic compound required as a nutrient in tiny amounts by an organism. In other words, an organic chemical compound is called a vitamin when it cannot be synthesized in sufficient quantities by an organism, and must be obtained from the diet. Thus, the term is conditional both on...

s, mineral

Mineral

A mineral is a naturally occurring solid chemical substance formed through biogeochemical processes, having characteristic chemical composition, highly ordered atomic structure, and specific physical properties. By comparison, a rock is an aggregate of minerals and/or mineraloids and does not...

s, and hormones to promote bone mineralization

Mineralization (biology)

In biology, mineralization refers to the process where an organic substance is converted to an inorganic substance.This may also be a normal biological process which takes place during the life of an organism such as the formation of bone tissue or egg shells, largely with calcium.This term may...

. Research also suggests that vitamin D may help maintain a healthy immune system

Immune system

An immune system is a system of biological structures and processes within an organism that protects against disease by identifying and killing pathogens and tumor cells. It detects a wide variety of agents, from viruses to parasitic worms, and needs to distinguish them from the organism's own...

and help regulate cell growth

Cell growth

and differentiation

Cellular differentiation

Iodine

One study reported a "potential danger of [iodine] deficiency disorders due to strict forms of vegetarian nutrition, especially when fruits and vegetables grown in soils with low [iodine] levels are ingested." Iodine, however, is usually supplied by iodized salt and other sources in first world countries

First World

The concept of the First World first originated during the Cold War, where it was used to describe countries that were aligned with the United States. These countries were democratic and capitalistic. After the fall of the Soviet Union and the end of the Cold War, the term "First World" took on a...

. Other significant sources of iodine include sea vegetables (seaweed) and bread made with dough conditioner

Dough conditioner

A dough conditioner is any ingredient or chemical added to bread dough to strengthen its texture or otherwise improve it in some way.Examples of dough conditioners include ascorbic acid, monoglycerides and diglycerides, ammonium chloride, enzymes, DATEM, and calcium salts such as calcium...

Riboflavin

According to the American Dietetic Association, “Some studies have shown vegans to have lower intakes of riboflavin

Riboflavin

, compared with nonvegetarians; however, clinical riboflavin deficiency has not been observed.”

External links

United States Department of Agricolture. Vegetarian Diets.
Food and Nutrition Information Center, USDA. Vegetarian Nutrition Resource List.
Mayo Clinic. Vegetarian diet: How to get the best nutrition.
Medline Plus. Vegetarian Diet.
International Congress on Vegetarian Nutrition.
Vegetarian Nutrition Dietetic Practice Group.
The Vegetarian Society of the United Kingdom.

The source of this article is wikipedia, the free encyclopedia. The text of this article is licensed under the GFDL.

Benefits of a vegetarian diet

Potential nutrient deficiencies

Protein

Combining proteins

Iron

Zinc

Vitamin B₁₂

Omega-3 fatty acids

Vitamin D

Iodine

Riboflavin

See also

Further reading

External links