Introduction

This page gives a brief description of nutrients needed for the human body, and lists some vegetarian and vegan sources for each.

The diet that VNV recommends is a vegetarian diet that contains a wide variety of plant-based foods - fruits, vegetables, nuts, seeds and legumes, with wholegrain foods in preference to "white" processed foods (e.g. brown rice instead of white). Eating a wide range of foods is the key. Dairy foods and eggs are optional - they are not needed for health but some vegetarians like to eat them for convenience and/or for the taste. It is also ok to have small amounts of chocolate, sweet biscuits, chips, ice cream etc. as long as this does not displace the basis of the diet outlined above.

Vegetarians who eat a very limited range of foods or who are very fussy eaters can have health problems just like a very fussy meat eater who eats a limited range of plant foods. Nutrients that may be of concern for vegetarians who do not follow a properly balanced diet are protein, iron and zinc. Nutrients of concern for vegans who eat a poor diet are protein, iron, zinc, calcium and of course vitamin B12. A vitamin B12 supplement, or regular consumption of foods fortified with B12, is recommended for vegans in any case due to the fact that B12 is only found in significant quantities in animal products.

Dietitians

A vegetarian or vegan diet can be very healthy and is not that difficult to plan properly. But as just mentioned, there can be problems if one is careless about what one eats. If you are concerned about your diet, or if you feel you may not be eating properly, it is advisable to see a dietitian. Even just for peace of mind.

For information on dietitians refer to our Dietitians page.

Vitamins & Minerals

Vitamins
The term vitamin is derived from the words "vital" and "amine", because vitamins are required for life and were originally thought to all be amines. Vitamins are organic compounds required in small amounts from the diet for many of the processes carried out in the body. An organic compound is considered a vitamin if a lack of that compound in the diet results in overt symptoms of deficiency. Usually only a few milligrams (mg) or micrograms (µg) are needed per day, but these amounts are essential for health. Vitamins have been traditionally grouped into two categories; the fat soluble vitamins, and the water soluble vitamins.

Minerals
Minerals are elements that originate in the Earth and cannot be made by living systems. Plants obtain minerals from the soil, and most of the minerals in our diets come directly from plants or indirectly from animal sources. Minerals may also be present in the water we drink, but this varies with geographic area. Minerals from plant sources may also vary from place to place, because soil mineral content varies geographically.

Recommended Dietary Intakes (RDIs)

Recommended Dietary Intakes (RDIs) are the levels of intake of essential nutrients considered to be adequate by the National Health & Medical Research Council to meet the known nutritional needs of practically all healthy people. The RDIs incorporate generous factors to accommodate variations in absorption and metabolism. They therefore apply to group needs. RDIs exceed the actual nutrient requirements of practically all healthy people and are not synonymous with requirements. For example, the RDI for Niacin includes a safety factor of 50%.

Please note that the RDIs listed below are for adults of approximately 19-64 years of age. Different RDIs are used for infants, young children, children, teenagers, pregnant and lactating women, and the elderly, so they are to be used as a guide only. If you would like information on the RDIs for these other groups please refer to the National Health and Medical Research Council Recommended Dietary Intakes for use in Australia page, in particular Appendix 1: Recommended dietary intakes.

As well as the tables below, the following resources allow you to easily look up the nutrient content of thousands of different foods:
- US Dept. Agriculture Nutrient Database. This site allows you search by nutrient or name or food and
  displays quite detailed nutrient information.
- NutritionData Nutrition Facts Analyser. NutritionData (ND) generates nutrition facts and
  provides simplified nutritional analyses for foods and recipes. Includes facts on food from
  fast food restaurants. ND tells you what's good and bad about the foods you eat, and
  helps you select foods that best meet your dietary needs. Use ND's Nutrient Search Tool
  to find the foods that are lowest in carbohydrates, highest in protein, or that match any
  other dietary restrictions or goals.
Please note that the data in both these resources is based on foods in the US.

 

Nutrients List

Essential Fatty Acids (Omega-3)
Protein
Water-Soluble Vitamins:
        B Group:
               Vitamin B1 (Thiamin)
               Vitamin B2 (Riboflavin)
               Vitamin B3 (Niacin)
               Vitamin B5 (Pantothenic Acid)
               Vitamin H (Biotin)
               Vitamin B6 (Pyridoxine)
               Vitamin B9 (Folate)
        Vitamin B12 (Cobalamin)
        Vitamin C (Ascorbic Acid)
Fat-Soluble Vitamins:
         Vitamin A (Retinol)
         Vitamin D (Cholecalciferol)
         Vitamin E (alpha-Tocopherol)
         Vitamin K (Menadione)
Water and the Electrolytes:
          Sodium
          Chloride
          Potassium
Minerals:
          Iron
          Zinc
          Calcium
          Phosphorus
          Magnesium
Essential Trace Minerals:
          Copper
          Iodine
          Chromium
          Selenium
          Molybdenum

In the above list:
  - Vitamins listed from Vitamin B1 (Thiamin) through to Vitamin B6 (Pyrodoxine) are
     involved in Energy Metabolism
  - Vitamins listed from Vitamin B6 (Pyridoxine) through to Vitamin B12 (Cobalamin) are
     involved in Haematopoiesis (the formation of blood cells in the body).

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Nutrient Summary

Water-Soluble Vitamins:

B Group:

Vitamin B1 (Thiamin)

Thiamin is needed to release energy from carbohydrate. The amount required is related to the amount of carbohydrate eaten. Deficiency of Thiamin causes Beri-Beri, a disorder of the nervous system, which occurs in communities where white rice is the main food eaten. A different type of Thiamin deficiency which affects brain function (Wernicke-Korsakoff Syndrome) is sometimes seen in alcoholics.

Requirements and RDI
RDI: 0.1 mg/1000kJ/day (since Thiamin is required for energy generation the RDI is expressed per kJ intake). This equates to approximately 1.1 mg for men and 0.8 mg for women.

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Vitamin B2 (Riboflavin)

Riboflavin is required to release energy from protein, carbohydrate and fat. Although there is no specific deficiency disease, low intakes lead to symptoms such as dryness and cracking of the skin around the mouth and nose. Excess Riboflavin is excreted in the urine.

Requirements and RDI
RDI: 0.15 mg/1000 kJ/day (since Riboflavin is required for energy generation the RDI is expressed per kJ intake). This equates to approximately 1.7 mg for men and 1.2 mg for women.

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Vitamin B3 (Niacin)

The central role of Niacin is in the breakdown of carbohydrates, fats and proteins into usable energy. It is found in most foods and can also be made by the body from the amino acid tryptophan. Deficiency results in a disease called Pellagra. Excess intakes from vitamin supplements may be dangerous.

Requirements and RDI
- Niacin equivalent (NE) = Dietary Niacin (mg) + Tryptophan (mg)
                                                                               60
- RDI: 1.6 mgNE/1000 kJ/day (since Niacin is required for energy
  generation the RDI is expressed per kJ intake). This equates to
  approximately 19 mg for men and 13 mg for women.

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Vitamin B5 (Pantothenic Acid)

Pantothenic Acid is needed for the breakdown of carbohydrates, proteins and fats. It plays a number of essential metabolic roles in the human body, including the production of energy. Deficiency is virtually impossible.

Requirements and RDI
- No RDI exists because of Vitamin B5's widespread
  distribution in food. Instead an ESADDI (Estimated Safe
  and Adequate Daily Dietary Intake) is specified.
- ESADDI: 4-7 mg/day.

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Vitamin H (Biotin)

Biotin is essential for the metabolism of proteins and carbohydrates, and in the synthesis of hormones and cholesterol. Deficiency is rare as the small amounts required are usually readily available in the diet

Requirements and RDI
- No RDI exists. Instead, an ESADDI (Estimated Safe and
  Adequate Daily Dietary Intake) is specified. Dietary
  requirements are not known with certainty, partly because
  of the unknown and variable amount of Biotin synthesised
  by bacteria in the large intestine.
- ESADDI: 30-100 µg/day.

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Vitamin B6 (Pyridoxine)

The main role of Vitamin B6 (Pyridoxine) is in the metabolism of protein. Deficiency may occur as a complication of disease and drug effects.

Requirements and RDI
RDI: 0.02 mg/g protein/day. This equates to approximately 1.3-1.9 mg for men and 0.9-1.4 mg for women.

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Vitamin B9 (Folate)

Folate is involved in the formation of red blood cells. Its absence leads to neural tube defects (e.g. spina bifida) in the developing foetus during pregnancy and megaloblastic anaemia. Most breakfast cereals and some breads are now fortified with Folate to help prevent neural tube defects. Deficiency may be due to poor diet or increased requirement, e.g. in pregnancy, from drug interaction and due to malabsorption. Higher intakes of Folate (obtained through supplements), before conception and during the first twelve weeks of pregnancy reduces the incidence of neural tube defects in babies.

Requirements and RDI
RDI: 200 µg/day.

* A landmark study demonstrated that Folate supplementation has a profound
  impact on the occurrence of neural tube defects in babies. Since these
  findings, many manufactured foods (mostly breakfast cereals and bread)
  have been supplemented with Folate.

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Vitamin B12 (Cobalamin)

Vitamin B12 (Cobalamin) is used in the formation of blood cells and the myelin sheaths along nerves. All naturally occurring vitamin B12 is synthesised by micro-organisms, and any vitamin present in food is the result of bacterial contamination. Faeces contains a large quantity of vitamin B12 because of the actions of micro-organisms in the large intestine, but synthesis occurs beyond the point at which the vitamin is absorbed. In western countries dietary intake is exclusively from animal sources. Edible seaweeds, mushrooms, fermented soy foods (eg. miso, tempeh) and spirulina, which have been promoted as good sources of B12, actually contain B12 analogues, which are structurally very similar to B12 but are inactive. It is therefore strongly recommended that vegans regularly take a B12 supplement or regularly consume sufficient quantities of B12-fortified foods (e.g. some soymilks). Deficiency can occur in vegans but it is also caused by a lack of intrinsic factor - the substance needed for the absorption of vitamin B12. Deficiency leads to megaloblastic anaemia in which red cells are enlarged (megaloblasts), and to neurological damage.

For more information please refer to the following articles:
   - Vitamin B12 and Vegan Diets
   - Veganism and Vitamin B12
The extensive article Vitamin B12: Are You Getting It?, by Jack Norris, Registered Dietitian, is also an excellent and very comprehensive resource on vitamin B12.

Requirements and RDI
RDI: 2.0 µg/day.

* Soymilks in some states of Australia may not be fortified. Check the label.

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Vitamin C (Ascorbic Acid)

Ascorbic Acid is a water soluble vitamin required for the production of collagen - the protein in connective tissue. It also helps the body absorb iron from plant sources (non-haem iron), it is an antioxidant, and it is vital for the function of the immune system. Severe deficiency leads to scurvy. This disease is characterised by bleeding gums, poor wound healing and damage to bone and other tissues. It is rarely seen today, although it may occur very occasionally in older adults. If the body is under stress, there is increased demand for ascorbic acid. Smoking is one such stress, and smokers should ensure they eat foods and drinks containing Vitamin C. Some people take very large amounts of Ascorbic Acid (several grams) as it has been claimed to prevent or cure the common cold, but this is yet to be proved.

Requirements and RDI
- RDI: 40 mg/day for adult males, 30 mg/day for adult females.
- The body is totally saturated at intakes of about 150 mg/day.

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Fat-Soluble Vitamins:

Vitamin A (Retinol)

Vitamin A is essential for normal growth and development. Deficiency leads to increased susceptibility to infectious disease, dry and rough skin, poor night vision and eventually to blindness. Vitamin A is found in two forms: as Retinol in foods from animal sources, and as Carotenoids in foods from plant sources, b-Carotene being the most common. b-Carotene can be converted to retinol in the body.
Excess Retinol can be toxic and may be particularly dangerous for the unborn child. It is for this reason that women who are pregnant, or who might become pregnant are advised not to take high-dose Vitamin A supplements unless advised to do so by a health professional.
In Australia, margarines are fortified with Vitamin A (and Vitamin D).

Requirements and RDI
- Retinol Equivalent (RE) = 
            Dietary Retinol (µg) + b-Carotene (µg) + other Carotenoids (µg)
                                                      6                           12
- RDI: 750 µgRE/day.
- Most margarines in Australia are fortified with Vitamin A.

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Vitamin D (Cholecalciferol)

Vitamin D is found in two main forms: Cholecalciferol and Ergocalciferol. the active form of Vitamin D works as a hormone in controlling the amount of calcium absorbed by the intestine, and it is essential for proper bone mineralisation.
Vitamin D is obtainable from food but is also made by the action of ultra violet rays on the skin and this is the most important source for the majority of people since few foods contain significant amounts of Vitamin D.
Deficiency of Vitamin D leads to skeletal deformity in children (Rickets) and to painful bones and muscle weakness in adults (Osteomalacia).

Requirements and RDI
- There is no RDI for adults in Australia due to assumed exposure to sufficient sunlight.
  For children, 10 µg/day is recommended.
- Most margarines in Australia are fortified with Vitamin D.

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Vitamin E (alpha-Tocopherol)

Vitamin E is a group of compounds called Tocopherols, of which a-Tocopherol is the most active. Vitamin E acts as an antioxidant in preventing the oxidation of lipids in cell membranes. This protection of cell membranes may improve immune system response and lower the risk of cardiovascular diseases and cancer. The amount of Vitamin E needed in the diet is related to the amount of polyunsaturated fatty acids consumed. Deficiency is rare due to the plentiful supply in the diet and the body's ability to store it.

Requirements and RDI
- The more polyunsaturated fats in the diet, the more Vitamin E required.
- a-Tocopherol Equivalent = (mg a) + (0.4 mg b) + (0.01 mg g) + (0.1 mg d)
- RDI: 10mg a-Tocopherol equivalents/day

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Vitamin K (Menadione)

Vitamin K is found in foods from both plant and animal sources and is also made by bacteria in the intestine. Vitamin K is essential for the clotting of blood. Deficiency is very rare in adults, but is sometimes seen in new-born babies. To prevent this, Vitamin K is normally given routinely after birth.

Requirements and RDI
Vitamin K is abundant in the diet and deficiency is uncommon. There is uncertainty with regard to setting an RDI because of the variable production of Vitamin K by bacteria in the colon. The requirement is believed to be 1 µg/kg body weight/day and most adult intakes are above this level.

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Water and the Electrolytes:

Sodium

• Principal cation in extracellular fluid (90%).

• Roles:
  - major role - regulating extracellular fluid volume, and hence is essential for normal growth and existence.
  - transport of chemicals (often glucose or amino acids) across selectively permeable membranes, usually via facilitated transport. This Sodium co-transport increases the concentration of Sodium in the cell.
  - conduction of nerve impulses and muscle contraction.

• Absorption
  Sodium is readily absorbed from the small intestine (the absorption of glucose is dependent upon the transport of Sodium into the small intestinal cells).

• Excretion
  Sodium is filtered from the plasma in the kidneys. Around 70% of the Sodium filtered by the kidneys is actively reabsorbed, a process controlled by aldosterone. Sodium is also lost through perspiration.

• Dietary sources
  The major source of Sodium in Australia is processed food and table salt (1/2 to 1/3 is added during cooking or at the table). The recommended level of Sodium intake in adults is between 920 and 2300mg/day.

• Hypertension
  A relationship between Sodium intake and blood pressure has been established. However, blood pressure was shown to be most closely associated with the age of the individual, with body mass and alcohol consumption being the next most important factors. Only 20% of the increases in blood pressure in a population can be attributed to Sodium intake. In hypersensitive people salt restriction does have a small but significant impact on blood pressure.

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Chloride

• Major anion in extracellular fluid.

• Salt is composed of both Sodium and Chloride. Chloride is usually associated with Sodium.

• Roles:
  - the major anion in the extracellular fluid, and therefore important in regulating water distribution
  - used in the stomach in the synthesis of hydrochloric acid
  - regulation of acid-base balance.

• Ordinary diets contain sufficient quantities of Chloride.

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Potassium

• The major cation of intracellular fluid; it is a nearly constant component of lean body tissue.

• Potassium is present in every cell in the body. The concentration of Potassium is very closely regulated inside the cell, thus Potassium has been used as a measure of lean body mass.

• Roles:
  - a major component of bone.
  - works with Sodium in the conduction of nerve impulses.

Requirements and RDI
RDI: 1950-5460 mg/day.

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Minerals:

Iron

Iron is an essential part of haemoglobin (the part of the red blood cell that carries oxygen). It is also involved in energy metabolism.
Anaemia develops from Iron deficiency, and is one of the most common nutritional problems around the world. It most commonly occurs in young children, pregnant women, and the elderly.

For more information please refer to the following article:
- Iron and Vegetarian Diets

Requirements and RDI
RDI: men - 7 mg/day; pre-menopausal women - 12-16 mg/day; post-menopausal women - 5-7mg/day.

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Zinc

Zinc is important for growth and development. It affects many of the body's major functions including: protein synthesis and digestion, wound healing, white blood cell immune function, and the synthesis of DNA. Groups most vulnerable to deficiency are children and pregnant women (those who are growing, reproducing or synthesising new tissue). The elderly are also at risk of Zinc deficiency because as we get older our ability to absorb and utilise Zinc decreases.

Requirements and RDI
RDI: 12 mg/day.

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Calcium

Calcium is needed for strong bones and teeth, for blood clotting, and for normal nerve impulse transmission and muscle contraction.
If low calcium intakes are maintained prior to maturity, growth retardation can occur. Long-term low calcium intake can cause Osteoporosis, which refers to loss of bone density. Only after many years are signs apparent.

Requirements and RDI
- RDI: 800 mg/day.
- There has been some discussion about whether the RDI has been set too high. In Asia dairy products are not regularly consumed, and Calcium intakes are below half of the Australian RDI, yet no clear signs of deficiency are seen. (Their Calcium absorption is enhanced for their intake to meet their needs.) RDI is generous due to osteoporosis being a problem in the elderly population, and a moderately high intake believed to have no known detrimental effects.

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Phosphorus

As a component of ATP, Phosphorus (phosphate) participates in every energy-requiring reaction. It is a component of DNA, RNA and cell membranes (phospholipids). It is also needed in the regulation of proteins in metabolism, cell division and cell maturation, and in the formation of bone. No deficiency disease is currently associated with a deficient Phosphorus intake.

Requirements and RDI
RDI: 1000 mg/day.

* Phosphorus from nuts, seeds, and grains is about 50% less bio-available
   than Phosphorus from other sources

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Magnesium

Magnesium possesses a range of functions and affects various systems within the body. It is involved in energy metabolism, nucleic acid synthesis, DNA and RNA transcription, protein synthesis, and muscle contraction. Deficiency is rarely seen

Requirements and RDI
RDI: 320 mg/day for adult males, 270 mg/day for adult females.

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Essential Trace Minerals:

Copper

• Copper is widely distributed in biological tissues, where it is present complexed to many metalloenzymes.

• It is absorbed by a carrier-mediated process in the small intestine and is stored in the liver.

• Main Functions:
  - part of certain enzymes (e.g. those that form cross-links in collagen and elastin, and
    produce norepinephrine)
  - contributes to activity of other enzymes
  - aids in iron metabolism (increases absorption)
  - it may also play a role in the body's thermal regulation, cholesterol metabolism,
    glucose metabolism, as well as immune & cardiac functions.

• Dietary sources: widely distributed in plant and animal foods, with the amount reflecting the concentration in the soil. Drinking water obtained through copper pipes is also a source.

• Deficiency: bone fragility and anaemia.

Requirements and RDI
Currently there is not enough data to establish an RDI for Copper.

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Iodine

• Iodine is absorbed in the small intestine. Most of the absorbed Iodine is removed from the blood from the thyroid gland. Excess is excreted in urine.

• In the thyroid, Iodine is used to produce the hormones T₄ (thyroxine) and T₃ (tri-iodothryronine). These hormones play an important role in the regulation of growth, development, and energy metabolism.

• Content in food differs markedly and reflects the concentration in the soil. Cooking reduces levels by 20-60%.

• Iodine salts have been added to bread and milk in Australia and these are the predominant food sources.

• Iodine deficiency is a major health problem in many nations. Effects on growth are and development are collectively termed iodine-deficiency disorders (IDD). Effects on the foetus in order of deficiency severity: mild to severe mental impairment; brain and neurological defects (the most common form of neurological impairment is called cretinism (deafness, muteness and characteristic gait)); death. In adults, deficiency causes goitre - the characteristic enlargement of the thyroid.

• Iodine supplementation may lead to hyperthyroidism - high metabolic rate, high body temperature, and loss of body weight.

Requirements and RDI
RDI: 150 µg/day for adult males, 120 µg/day for adult females.

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Chromium

• Chromium affects many of the body's metabolisms, including: glucose, carbohydrate, lipid, and protein metabolism.

• It increases the action of insulin (termed "the glucose tolerance factor).

• It is absorbed poorly (<1%). Once absorbed it is transported in the blood bound to transferrin.

• Lost from the body largely in urine.

• Low toxicity

Requirements and RDI
Currently there is no RDI specified for Chromium.

* Because Chromium content in different batches of the same food has been found to
  vary significantly,  the information in the table above should serve only as a guide to the
  Chromium content of foods. 

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Selenium

• Important component of the enzyme glutathione peroxidase, which is an important component of the body's antioxidant defences.

• Contained in some other enzymes.

• Involved in production of the thyroid hormones T₃ and T₄.

• Deficiency is rare. In China, is characterised by a form of heart disease (unlikely to be solely due to Selenium deficiency).

• Some anti-oxidant supplements (not in Australia) contain significant amounts of Selenium and can lead to toxicity.

Requirements and RDI
RDI: 85 µg/day for adult males, 70 µg/day for adult females.

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Molybdenum

• Molybdenum is an essential nutrient required for several enzymes.

• It interacts with Iron and Copper.

• High intakes inhibit Copper absorption.

Requirements and RDI
Currently there is no RDI specified for Molybdenum.

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References:

Langley, G. (1991). Vegan Nutrition. A Survey of Research. The Vegan Society Ltd, East Sussex.

Messina, M. & V. (1996). The Dietitian's Guide to Vegetarian Diets. Issues and Applications.  Aspen Publishers, Inc., Maryland.

National Food Authority (1992). Nutritional Values of Australian Foods. Department of Community Services and Health. Australian Government Publishing Service, Brunswick, Vic.

National Health & Medical Research Council (1991). Recommended Dietary Intakes for Use in Australia. Australian Government Publishing Service, Canberra.

The Linus Pauling Institute Micronutrient Information Centre 
This website is a source for up-to-date, scientifically accurate information regarding the roles of specific vitamins, minerals, phytochemicals (plant chemicals that may affect health), and other nutrients in preventing disease and promoting health.
Refer: www.orst.edu/dept/lpi/infocenter