Vitamins Guide

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Vitamins are chemical compounds that are essential for normal growth and metabolism. They also help to convert the food we eat into energy and living tissues, such as bones, muscles, blood, nerves and skin. Vitamins also help the body resist infection and protect body cells.

Vitamins are only needed in tiny amounts. They cannot be made by the body, the exception being vitamin D. We must get vitamins from our food, and most vitamins are not stored in the body for long so they must be replenished regularly.

New research suggests a greater role for vitamins, and minerals, in the prevention or slowing down of many diseases, such as heart disease, cancer, cataracts, osteoporosis and birth defects.

Vitamin supplements are not a substitute for a healthy diet, but may be needed by people who cannot get enough from food. This may result from illness or special increased requirements. Large doses of vitamins or minerals can be toxic and should only be taken under medical supervision.

There are two broad groups of vitamins:

(a) Fat soluble vitamins: Vitamins A, D, E, K and beta-carotene.
(b) Water soluble vitamins: B vitamins, (B1, B2, B3, B6, B12) vitamin C and folate.

 

Recommended Dietary Intake

RDI is the abbreviation for Recommended Dietary Intake.

RDIs are the amounts of essential nutrients that are considered adequate to meet the nutritional requirements of healthy people.

The RDIs are designed to easily prevent nutritional deficiency diseases such as scurvy, beri-beri, pellagra, rickets and anaemia. There is a wide margin of safety.

The RDIs do not address the extra nutrient needs of persons who have certain chronic ailments, who smoke, or who are on drug medication.

Further, there is increasing scientific evidence to suggest that higher levels of certain vitamins (e.g. vitamins C, E and beta-carotene) may be needed for optimal health, and may provide extra protection against cancer, heart disease and other diseases.

In time, the concept of RDI may well be broadened to include a second set of much higher vitamin levels that optimise their disease-preventing properties.

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Persons At Risk of Vitamin Deficiency

Many people are vulnerable to nutritional deficiencies. Improving the quality of the diet as well as sensible supplementation may benefit such persons. They include:

• Elderly persons who: are light eaters; find preparation and cooking of food an effort; unable to chew or swallow properly; on drug medications which may reduce appetite or increase vitamin/mineral needs.
• Teenagers & young adults who lead erratic lifestyles and tend to eat haphazardly.
• Women on oral contraceptives; heavy menstrual blood losses; osteoporosis; pregnancy; breast-feeding; premenstrual syndrome; sports anaemia.
• Cigarette smokers require extra vitamins; e.g. vitamin C and E, beta-carotene.
• Heavy alcohol intake encourages poor dietary habits. Many drinkers lack B vitamins, vitamin C, magnesium and zinc.
• Dieters, dancers and models who overly restrict quantity and variety of foods.
• Persons on long-term drug medication: Many commonly prescribed drugs can interfere with nutrient absorption and metabolism, or may cause nausea, loss of taste, and reduce appetite.

  Such drugs may include: oral contraceptives, anti-inflammatory drugs, anti-depressants, certain anti- histamines, digoxin, chemotheraphy drugs, antibiotics, some diuretics and laxatives. Alcohol and coffee can also interfere with the absorption of nutrients.

• Vegetarians who are vegans (no dairy or eggs) may lack vitamin B12 and iron.
• Persons with intestinal mal-absorption.
• Persons with Chronic Ailments: Medically directed supplementation may benefit many medical conditions.
• 
  (Do not stop your current medication unless directed by your doctor.)

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Hints To Prevent Vitamin Loss

• The stability of vitamins is greatly influenced by the way food is handled, stored and cooked. Some vitamins are more stable than others.
• Storage: The longer the storage period, the greater the vitamin loss. Shop more frequently for fresh fruits and vegetables. Frozen vegetables and fruits are fresher and retain their nutrients longer than poorly stored 'fresh' produce. Avoid dehydrated vegetables.
• Minimise exposure to air and oxygen which can destroy some vitamins. Avoid buying precut produce. Cut up fresh produce at the last moment. Scrub vegetables clean rather than peeling them. Don't let frozen vegetables thaw longer than is necessary.
• Use minimum amounts of water in cooking to avoid loss of water-soluble vitamins, B & C, and leaching out of minerals. Cook vegetables whole or in large chunks to lessen the surface area exposed.
• Cooking methods which are quick and limit exposure of foods to high temperatures are preferable; e.g. steaming, stir-frying and microwaving. Cook vegetables until they are soft but still crispy and colourful. Meats are best grilled or stir-fried rather than roasted. Serve food immediately after cooking.
• For freshest produce, ideally grow your own vegetables. Many varieties are easy to grow and ideal for small spaces or containers.

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Antioxidants & Free Radicals

Free radicals are highly unstable particles that are produced in body cells as a normal part of metabolism; e.g. as a by product of fat oxidation. They are also created in the body by exposure to sunlight, x-rays, and pollutants such as tobacco smoke, car exhaust and ozone.

Free radicals attack body cells in a number of ways. They can damage mitochondria (the cells own energy powerhouses), rupture cell membranes, and damage DNA thereby altering or destroying cell function.

The body can normally cope with low levels of free radicals but high levels may initiate or contribute to premature ageing, atherosclerosis and heart disease, cancer, cataracts, arthritis, infertility in men, and other degenerative diseases.

Antioxidants

Antioxidants are substances that combat or neutralise free radicals before excessive damage occurs to our body cells. They are an active area of research and much of what is known is speculative. Nevertheless, antioxidants show promise as agents that can prevent or delay many disease processes.

The emerging picture also strengthens the current dietary advice for individuals to eat a wide variety of foods with an emphasis on plant-based foods.

A wide range of dietary antioxidants include vitamins, minerals and phytochemicals (including carotenoids):

Vitamins: Vitamins E, C and beta-carotene are the most studied antioxidants for which important roles have been proposed.

Minerals: Selenium, zinc, manganese and copper have important roles as do various enzymes such as SOD, Co-Q10 and glutathione peroxidase.

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Carotenoids

Carotenoids are a large family of red, yellow and orange pigments in fruits and vegetables of which beta-carotene is just one (p.222). As well as having antioxidant properties, they are thought to be potent cancer fighters. Some specific ones that have gained the interest of researchers include:

Lycopene gives tomatoes their red colour. It is linked to a lower risk of prostate cancer in men. In one study, men who ate at least 10 servings of tomato-based foods each week had 45% less risk. Tomato sauce and tomato puree are also good sources of lycopene.

Lutein and zeaxanthin in spinach and broccoli have been linked to eye health in the elderly. (Vit C, E and beta-carotene may also prevent or delay onset of cataracts.)

Note: Eat at least three different colours of fruit and vegetables each day.

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Phytochemicals

Phytochemicals are a new class of non-vitamin compounds found in all fruits and vegetables. Early research is speculative but show them to be potential cancer protectors. They seem to interact with every step in the cancer process, by slowing, stopping or reversing them.

Phytochemicals include: flavonoids including catechins (mainly in green and black tea and wine to a lesser extent; strong antioxidant action); indoles and isothiocyanates (mainly responsible for broccoli's anti-cancer story); isoflavones including phytestrogens (prominent in soy beans); lignans (in many plant foods, soybeans, sesame seeds and flax seed); organosulfur compounds (in garlic and onions); monoterpenes (in citrus fruits and caraway seeds); saponins (in soybeans, nuts, chickpeas); cruciferous chemicals with anti-cancer properties (in broccoli, cabbage, cauliflower, brussels sprouts).

Dietary Recommendations

For a balance of beneficial phytochemicals, eat at least three different colours of fruit and vegetables every day (as part of the recommended 7 servings per day). Include food from each of the following categories:

• cruciferous vegetables: broccoli, cabbage, cauliflower, brussels sprouts, kohlrabi
• citrus fruits for vitamin C such as oranges, grapefruit (See Vitamin C - p.226)
• dark green and leafy vegetables such as spinach, kale, green capsicum, mustard greens, lettuce, silverbeet
• deep yellow/orange/red: tomatoes, red capsicum, carrots, rockmelon, pumpkin, sweet potato, mango, pawpaw

Additionally, include other plant foods:

• soybeans and soy foods: tofu, tempeh, soy milk drinks (preferably calcium-enriched)
• other dried beans, wholegrains, nuts and seeds, potatoes, rice.

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Phytestrogens

Phytestrogens are plant hormones that are very weak versions of human oestrogen.

While different types of phytestrogens are widespread in plant foods, it is the isoflavones (Genistein and Diadzn) in soybeans and soyfoods that has the most potent oestrogen-like effects on the body.

In countries where people eat diets high in soyfoods, such as Japan, China and Korea, breast cancer rates are much lower than in the West, prostate cancer deaths are minimal and unpleasant symptoms of menopause appear scant (There is no word for 'hot flush' in Japanese).

Breast Cancer
During childbearing years, phytestrogens stave off breast cancer by blocking some of the naturally occurring oestrogen thereby acting as anti-estrogens. (Even though oestrogen is necessary for reproduction it can also encourage cancerous tumours to develop in breast tissue.)

Menopause Benefits
At menopause, however, when a woman's natural oestrogen declines by 70 percent, phytestrogens provide an oestrogen 'lift' to make up for the 'lack' of the hormone without raising the cancer risk. This may reduce the symptoms of menopause such as hot flushes, headaches and mood swings.

Further bonuses for menopausal women consuming soy-rich phytestrogens may include:

• reduced risk of osteoporosis - by lessening the bone loss that accompanies oestrogen fall-off at menopause.
• reduced risk of heart attack. Oestrogen raises the 'good ' HDL cholesterol which keeps arteries clear.
• reduced thinning of vaginal tissues.

Prostate Cancer
In men, phytestrogens appear to act as a blocker of testosterone - the male hormone that, while necessary for a man's maleness, can spur the growth of prostate tumours. Phytestrogens accomplish the task without making men 'feminine'.

Note: Soy protein can lower high blood cholesterol levels.

Level Of Soy Intake

While the actual amounts for a protective effect have not yet been defined, researchers are currently examining intakes of 24- 40 grams of soy protein isolate per day. These amounts can be obtained from 3-5 serves of soy-based products per day. For example, 2 cups of soy drink in place of milk, and one or more serves of either soybeans, tofu or tempeh (Many creative recipes exist for their use.)

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Vitamins Mini-Guide  

Vitamin A & Beta-Carotene

Retinol is the commonest form of vitamin A.

Beta-Carotene is the most abundant form of provitamin A and converts to vitamin A as required by the body.
(1mg B-carotene = 166 mcg retinol)

RDI: 750 mcg (micrograms)
or 750 RE (Retinol Equivalents)
or 2500 IU (International Units)
or 4.5mg Beta-carotene

Functions of Vitamin A:

• Necessary for night vision
• Maintains healthy skin, eyes, body linings of lungs/intestines
• Supports sperm production
• May protect against cancer
• Boosts resistance to infection.

Deficiency Symptoms: Night blindness, dry eyes, rough skin, impaired bone growth. Deficiency makes linings of digestive and respiratory tracts more vulnerable to infection (for example to measles virus, and in HIV-infected persons.)

Toxicity: Large amounts of vitamin A (over 50,000 IU daily) taken over a period can be very toxic. Individual tolerance varies. Symptoms include headaches, loss of appetite, dry itchy skin, coarse hair, painful bone swellings, birth defects if taken in pregnancy.

Daily intake should not exceed 7500 mcg (25,000 IU) in adults, 1500 mcg (5000 IU) during pregnancy, and 3000 mcg (10,000 IU) in children.

Vitamin A Good Food Sources
 

	Retinol (mcg)
Liver, fried, 1 slice, 40g	14000
Cod Liver Oil, 1 Tbsp, 20ml	3600
Butter/Margarine,1Tbsp, 20g	240
Soy Extra , 250ml	125
Cheese, cheddar, 30g	120
Egg, 1 large	100
Milk, whole, 1 cup, 250ml	80
Sustagen, 250ml tetra pack	250

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Beta-Carotene

Beta-carotene only converts to vitamin A as required. It is not toxic even though large amounts can colour the skin. Apart from its role as provitamin A, beta-carotene acts as an antioxidant. Studies suggest a preventive role in cancer, stroke and heart disease.

Beta-carotene is just one of hundreds of other carotenoids and probably works best in combination with others.
Note: Skin damage by the sun's UV rays may be lessened by a diet rich in beta-carotene and other carotenoids.
If in the sun a lot, aim for 10-20mg beta-carotene daily, and of course, cover up and use a good sun screen.

Beta-Carotene Food Sources

Mainly found in deep yellow/orange/red and dark green fruit and vegetables.
Aim for at least 6 mg daily.
 

	Beta-Carotene Equivalents (mg)
Carrot Juice, 200ml	17
Carrot, 1 small or 1/2 large, 100g	10
Sweet Potato (orange), 1/2 cup, 100g	6
Mango, 1 medium	3.5
Pumpkin, cooked, 1/2 cup pieces, 100g	2.5
Spinach, cooked, 1/2 cup, 85g	2
Capsicum (red), 1/2 medium, 100g	1.5
Pawpaw, 1/4 small, 100g	1
Rockmelon, 1 large slice, 100g flesh	0.8
Persimmon, 100g	0.8
Tomato, 1 medium, 150g	0.5
Broccoli, 2-3 clusters, 100g	0.4
Peas, cooked, 1/2 cup, 70g	0.3
Beans, green, 1/2 cup, 60g	0.3
Avocado, 100g flesh	0.3
Peach, 2 medium	0.3
Plums, 2 medium, 200g	0.3
Apricots, 2-3 medium, 100g	0.2
Orange, 1 medium	0.2
Orange Juice, 250 ml cup	0.3
Watermelon, 100g flesh	0.2

 

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Vitamin B1 - Thiamine

RDI: 1.1 mg (1100mcg)
(0.1 mg per 1000 kJ/240 cals)

Functions:

• A co-enzyme that helps release energy from carbohydrate (converts into glucose)
• Stimulates appetite
• Keeps nerve cells healthy
• Maintains muscle tone.

Deficiency: More common in alcoholics, malnourished infants and elderly persons. Beriberi (loss of appetite, fatigue, nerve and muscle degeneration, mental confusion, staggering gait, heart failure, fluid retention); Wernicke-Korsakoff syndrome (double vision, faulty memory, abnormal behaviour).

Note: Alcohol interferes with thiamine absorption, storage and conversion into its active form. Alcoholics require large doses to combat effects (10-100mg).

Toxicity: None reported to date.

Good Food Sources

Whole grain cereals, dried beans, nuts, pork, liver, fish, bran, enriched rice, brewer's yeast, Vegemite, fresh green leafy vegetables.
 

	Thiamine (mcg)
Pork, cooked, 150g	750
Sustagen, 250ml tetra pack	600
Muesli, 1/2 cup, 60g	550
Bkfst Cereal, 1 cup, 30g	475
Vegemite, 1/2 tsp, 3g	540
Pasta, wholemeal, ckd, 1cup	360
Weet-Bix, 2 biscuits, 30g	280
Yoghurt, fruit, 200g ctn	200
Nuts, mixed, 1/4 cup, 40g	150
Peas, green, ckd, 1/3 cup, 55g	130
Orange, 1 medium	130
Soy Extra (Chemists Own), 250ml	125
Milk, whole/skim, 1cup, 250ml	100
Lentils, ckd, 1/3 cup,100g	80
Meat/Fish, ckd, 120g	70
Chicken, ckd, 120g	60
Potato, ckd, 1 medium	70
Bread, w/meal, 1 sl. 30g	70

 

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Vitamin B2 - Riboflavin

RDI: 1.7 mg (1700 mcg)
Functions: Necessary for protein, fat and carbohydrate metabolism, and for growth and healthy skin.
Deficiency: Inflammation of mouth and tongue; cracking/dryness of lips; lack of growth in children.

Good Food Sources

Milk, enriched soy drinks (e.g. Soy Extra), liver, eggs, dark green vegetables, cheese, lean meat, enriched cereals, nuts, brewer's yeast, Vegemite.
 

	Riboflavin (mcg)
Liver, fried, 1 serve, 40g	1800
Sustagen 250ml tetra pack	570
Vegemite, 1/2 tsp, 3g	660
Muesli, 1/2 cup, 60g	550
Soy Extra (Chemists Own), 250ml	500
Bkfst Cereal, 1 cup, 35g	480
Yoghurt, fruit, 200g ctn	460
Milk, whole/skim, 1 cup	400
Almonds, 1/4 cup, 45g	380
Meat, aver, ckd, 120g	320
Salmon, pink, cnd, 100g	250
Chocolate, 5-6 squares, 30g	170
Egg, ckd, 1 large	180
Banana, 1 medium	150
Fish, ckd, 1 fillet, 120g	120
Pasta, w/meal, ckd, 1cup	120
Bread, w/meal, 2 sl. 60g	70

 

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Vitamin B3 - Niacin or Nicotinic Acid

RDI: 20 mg (Children: 12-15mg)

Functions:

• Important for continual supply of energy to all cells
• Involved in metabolism of carbohydrates, protein and fats
• Maintains normal functioning of skin, nerves and digestive tract
• Enhances immune system.

Deficiency: Affects the skin, digestive tract and nervous system. Pellagra (diarrhoea, dermatitis, dementia); soreness and ulceration of mouth corners.

Toxicity: High supplemental dosages (1-4 grams) used as a drug to lower blood cholesterol, can cause nausea and skin flushing.

Good Food Sources

Fish, meats, liver, poultry, dried beans, nuts, yeast, Vegemite, wholegrain cereals.
 

	Niacin (mg)
Tuna, canned, 1/2 cup, 100g	23
Salmon, canned, 1/2 cup, 100g	17
Meat, average, ckd, 120g	12
Chicken, ckd, 100g	12
Fish, ckd, 1 fillet, 120g	11
Liver, fried, 1 slice, 40g	8
Peanuts, 1/4 cup, 40g	9
Hamburger, average	7
Nutrigrain, 30g serve	5.5
Muesli, 1/2 cup, 60g	5
Bread, w/meal, 4 slices, 120g	5
Pasta, w/meal, ckd, 1cup	4
Rice, brown, ckd, 1 cup	4
Weet-Bix, 2 bisc., 30g	3
Potato, 1 medium	3
Weeties, 30g serve	3
Soya Beans, 1/2 cup, 100g	3
Vegemite, 1/2 tsp, 3g	4
Avocado, 1/2 large, 100g	2
Mushrooms, 60g serve	2
Baked Beans, 1/2 cup, 150g	2
Egg, boiled, 1 medium	1

Stability: Niacin is relatively stable to heat and light. Little is lost in cooking.
 

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Vitamin B6 - Pyridoxine

RDI: 1.9 mg

Functions:

• Essential for metabolism of amino acids and protein
• Important for brain function
• Helps formation and growth of red blood cells
• Helps produce antibodies to combat allergens
• Enhances immune system
• Supplemental doses may help relieve PMT symptoms
• Lessens symptoms of carpal tunnel syndrome
• Helps correct metabolic imbalances caused by oral contraceptives.

Deficiency: Anaemia, irritability, weakness, insomnia, nervousness, skin problems.

Toxicity: Low up to 50 mg/day. Megadoses (2000 mg/day) may cause serious nerve damage (numbness in feet or hands, unsteady on feet).

Good Food Sources
Widespread in foods. Meats, liver, kidney, egg yolk, wholegrain cereals, beans, yeast, Soy Extra Drink (Chemists Own).
 

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Biotin

RDI: Not yet developed. 100-200 mcg/day is considered adequate and safe.

Functions:

• A coenzyme required for fatty acid synthesis
• Also helps metabolise amino acids and carbohydrate
• Helps maintain healthy skin, hair and a balanced hormonal system.

Deficiency: Rare. Deficiency can develop from excessive daily intake of over 12 raw egg whites (which contains a protein, avidin, that binds biotin and prevents its absorption; avidin destroyed by cooking). Symptoms include dermatitis, glossitis, lethargy, muscle pains, nausea.

Good Food Sources
Present in a variety of foods. Best sources include egg yolks, liver, yeast, nuts, milk, fresh vegetables.
Note: Intestinal bacteria provide most of our biotin requirements.
 

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Vitamin B12 -Cobalamin

RDI: 2 mcg (Children 1.5 mcg; Adults 2 mcg; Pregnancy 3 mcg; Lactating 2.5 mcg)

Functions:

• Essential for regeneration of red blood cells
• Helps make DNA and haemoglobin
• Maintains healthy nerves and mental abilities.

Deficiency: More common in elderly, breast-fed babies of vegan mothers, and vegans. (Body can store sufficient for 2-3 years.)

Symptoms: Pernicious anaemia: fatigue, pale yellow skin, anorexia, weight loss, apathy, depression. Glossitis (smooth red tongue).

Correction of marginal deficiencies may have invigorating effects; may speed up recovery from illness or surgery; may alleviate symptoms due to neurologic damage or deterioration of mental functioning. (B12 deficiency some-times misdiagnosed as Alzheimer's.)

Toxicity: No evidence of toxicity.

Good Food Sources

Meat, liver, eggs, dairy products, fish, Soy Extra Drink (Chemists Own). Negligible amounts in vegetables, grains, brewer's yeast, soy products (tofu, miso, tempeh and tamari). Very stable to heat. Alcohol can interfere with B12 absorption.
 

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Vitamin B5 - Pantothenic Acid

RDI: Not yet established. 4-7 mg daily considered adequate and safe.

Functions: Involved in metabolism of carbohydrates, fats, and protein.

Deficiency: Rare. Malaise, vomiting.

Good Food Sources
In a wide variety of foods. Highest amounts in meats, liver, kidney, yeast, fish, wholegrain cereals, dried beans, nuts, eggs, royal jelly of queen bees. Vegetables have moderate amounts. Most fruits have small amounts.
 

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Folate - Folic Acid

RDI: 200 mcg
Pregnancy - (400 mcg)
Lactation - (300 mcg)

Functions:

• Acts with B12 in producing haemoglobin for red blood cells.
• Essential for synthesis of protein and DNA in newly forming cells
• May protect against colon cancer (by guarding integrity of genetic messages encoded in DNA).

Deficiency: More common in pregnant women, the elderly and alcoholics. Macrocytic anaemia is an early sign of deficiency. Deficiency in pregnant women increases risk of Spina Bifida (spinal cord does not form properly) in the growing foetus. Risk is reduced by low dose supplement (400 mcg) before and during early months of pregnancy (since defect occurs by sixth week of pregnancy). Deficiency increases risk of cervical cancer.

Good Food Sources

Fresh leafy, green vegetables.
 

	Folate (mcg)
Broccoli, 100g	110
Brussel Sprouts,70g	60
Spinach, 3 leaves, ckd, 60g	85
Cabbage, raw, 50g	45
Green Peas, 60g	50
Orange, 1 medium	40
Fresh Orange Juice, 1 cup,	90
Avocado, 1/2 medium	100
Dried Bakerís Yeast, 1Tbsp,	400
Chicken livers, fried, 100g	500
Lentils/chick peas, ckd, 60g	25
Wheat Bran, 2 Tbsp	30
Bran bkfst cereals, 30g	30
Wheat Germ, 2 Tbsp, 20g	60
Wholegrain bread, 4 slices	40
Almonds, 30g	30
Liver, fried, 100g	240
Vegemite/Marmite, 1/2 tsp, 3g	30
Soy Extra, 2 cups, 500ml	30

Note: Folate is very unstable to heat and light. Cooking (particularly in water) destroys most of it.
 

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Vitamin C (Ascorbic Acid)

RDI: 40 mg; Pregnancy - 60 mg

Functions:

• Strengthens walls of body cells
• Promotes healthy gums, teeth, bones, joints
• Promotes formation of collagen, connective tissue
• Aids wound healing
• Strengthens walls of blood vessels
• Stimulates immune system and helps resist infections
• Aids iron absorption
• Antioxidant - protects vitamins A, E and polyunsaturated fatty acids from oxidation.

Deficiency: Scurvy symptoms include swollen bleeding gums, poor wound healing, easy bruising, aching joints, susceptibility to infection.
Other symptoms include: nose- bleeds, dry and itchy skin, anaemia, fatigue, psychological changes.
Vitamin C deficiency is more common in the elderly. Smoking, pollution and some medications destroy vitamin C.

Stability: Vitamin C is unstable to heat and can be washed out in cooking water. Also lost when food is cut or exposed to air.

Good Food Sources

Fresh fruit and vegetables.
 

	Vitamin C (mg)
Acerola Cherries, cup, 50g	820
Guava, 1 medium, 100g	180
Blackcurrant Cordial, dil., 1 cup	130
Orange Jce, fresh/pkg, 1 cup, 250ml	120
Capsicum: Red, chopped, 1/2 c., 60g	100
Green, chopped, 1/4 cup, 60g	55
Orange, 1 medium	60
Kiwifruit, 1 large, 80g	60
Rockmelon, 1 cup, diced, 160g	55
Cauliflower, ckd, 1/2 cup, 90g	50
Broccoli, 1 cluster, 45g	40
Cabbage, ckd, 1/2 cup, 70g	40
Mango, 1 medium	40
Grapefruit, 1/2 medium	40
Mandarin, 1 medium	30
Tomato, 1 medium, 150g	25
Strawberries, 6 medium	25
Potato, cooked, 1 medium	20
French Fries, 80g	20
Banana, 1 medium	15

 

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Vitamin D

RDI: Not yet established.

Major source of vit D is by activation of provitamin D2 in skin by sunlight. Most Australians receive sufficient sunlight. Elderly and housebound may rely more on food or a small supplement.

Functions:

• Involved in absorption and metabolism of calcium and phosphorus
• Promotes their movement in and out of bones and teeth.

Deficiency: More common in elderly persons. Poor bone growth, rickets (soft bones/enlarged joints), osteomalacia (adult rickets), softening of teeth, muscle twitching.

Toxicity: From excessive amounts of fish oils or supplements. Symptoms include anorexia, vomiting, intense thirst, alternating constipation and diarrhoea.

Good Food Sources

Vitamin D is fat-soluble and associated with fats/oils of fatty fish (sardines, herring, salmon), cod-liver oil, egg yolks, butter, cheese.
 

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Vitamin E - Tocopherol

RDI: 10 mg (15 IU) alpha-tocopherol
Note: 1 mg Vit E = 1.5 IU (I.U. = International Units)

Functions:

• Principal role as an important antioxidant that protects body cells and membranes from oxidation and 'free radical' damage.
• May reduce risk of cancer and heart disease
• Prevents oxidation of polyunsaturated fats and vitamins A and C
• May prevent oxidation of LDL-cholesterol which is toxic to cells lining artery walls.
• Protects lungs from air pollutants
• Enhances immunity
• Important in energy production
• May relieve leg cramps, angina, intermittent claudication
• May reduce symptoms of PMS.

Note: Recent research suggests that current RDI for vitamin E is too low. Protective benefits of vitamin E are more likely to be attained with daily doses of 30 - 400 IU. (Limit children to 200 IU)

Deficiency: Symptoms uncommon. Sub-clinical deficiency more common particularly in elderly.

Toxicity: Low. Above 400mg (600 IU), may cause fatigue and diarrhoea. High doses should not be taken if on anti-coagulant drugs. (Check with your doctor.)

Good Food Sources
Vegetable oils (and margarine), nuts and seeds, whole grain cereals, wheat germ.
Foods With Vitamin E
 

	Vitamin E (mg)
Wheat Germ Oil, 1 Tbsp, 20ml	27
Safflower Oil, 1 Tbsp, 20ml	8
Sunflower Seeds, 1/4 cup, 35g	9
Almonds, dried, 25 nuts, 30g	7
Hazelnuts, dried, 30g	7
Soybean Oil, 1 Tbsp, 30ml	2
Margarine, polyunsat. 30g	7
Tuna, canned in oil, 100g	6
drained of oil, 100g	2
Sweet Potato, 1 med. 130g	6
Peanut Butter, 1 Tbsp, 20g	4
Wheat Germ, 2 Tbsp, 20g	3
Peanuts, dried, 30g	3
Oatmeal, raw, 1/4 cup	2
Avocado; Mango, 1 medium	2.3
Spinach, 3 leaves, 60g	2
Navy Beans, dry, 1/2 cup	1.5
Parsley Sprigs, 2-3, 5g	1.5
Olive Oil, 1 Tbsp, 20ml	1
Asparagus (fresh), 60g	1
Broccoli, 100g	1
Mayonnaise, 1 Tbsp, 22g	1
Apple; Pear, 1 medium	1
Egg-Yolk, 1 large	1
Bread, whole grain, 2 slices	1
Walnuts, dried, 30g	1
Banana, 1 medium	0.5
Sustagen Sport, powder, 50g	7.7

Stability: Processing, refining and storage can deplete vit E. Unstable to heat, light, freezing.
 

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Vitamin K

RDI: Not yet established.
60-140 mcg is adequate and safe.

Functions:

• Important in formation of blood clotting factors which prevent bleeding; (K is derived from German 'koagulation')
• Plays role in bone mineralisation and fracture healing
• May help to protect against osteoporosis.

Deficiency: Uncommon as widely distributed in diet. Symptoms include easy bruising plus black/blue skin markings (also caused by other conditions)

Good Food Sources
Green leafy vegetables, spinach, broccoli, tomatoes, fruits, chickpeas, lentils, soybeans, fish, liver, cereals, dairy products, egg-yolks, soybean oil, seaweed.

Note: Vitamin K can also be made by intestinal bacteria.

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Minerals Mini-Guide  

Minerals

Minerals also play a vital role in body growth and maintenance. They are an important part of bones, teeth, hair, nails, red blood cells, body fluids, hormones, and enzymes.

Minerals help regulate metabolism, blood-clotting, heartbeat, acid-base and fluid balance; and aid in the function of nerves and muscles.

The essential minerals the body needs to survive form 2 groups:

• Macrominerals (more than 100mg/day required): Calcium, phosphorus, sodium, potassium, chloride, magnesium.
• Trace Minerals (much smaller amounts): Iron, zinc, copper, fluoride, iodine, selenium, cobalt, molybdenum, manganese.

Mineral Balance: The minerals in the body are maintained in proper proportions. It is a delicate balance that can be upset by certain diseases, as well as extreme forms of dieting or supplementation. The correct proportion or ratio of minerals can be kept by eating a wide variety of unrefined fresh foods.

Heavy Metals: The so-called 'heavy metals' include lead, mercury, cadmium and arsenic. They are toxic to man. They can contaminate the food supply as a byproduct of industrial processes. Breathing polluted air and cigarette smoke also contributes to heavy metal intake.

Stability of Minerals: Minerals are not destroyed by cooking. But, like vitamins, are often lost to trimming and peeling, or poured down the drain in cooking waters.
 

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Calcium

Cross-linked with Osteoporosis and Calcium Guide.
 

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Chromium

RDI: Not yet established. 50-200 mcg considered adequate and safe.

Functions:

• Essential trace element for carbohydrate and fats metabolism
• Part of the glucose tolerance factor (GTF) which promotes efficient insulin function. (Insulin helps regulate blood sugar levels, stimulates metabolism, and helps build and retain muscle tissue.)
• May protect against diabetes.

Deficiency: Difficult to assess. May take many years to develop and more likely to occur in elderly. Deficiency may contribute to 'maturity onset diabetes' (Type 2) and associated problems.

Notes:

1. The best indicator of chromium deficiency may be a beneficial response to a period of chromium supplementation.
2. Although no direct evidence that chromium can prevent diabetes, research shows chromium can improve glucose tolerance (and possibly reduce blood cholesterol).
3. Chromium losses may result from strenuous exercise, infection and physical trauma. High sugar diets increase chromium losses from the body.

Toxicity: Low

Good Food Sources
Brewer's yeast, (from chromium-rich barley), blackstrap molasses, egg yolk, cheese, liver, whole-wheat products, whole grains, wheat bran, wheat germ, meat, apple peel.
 

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Iron

Cross-linked with Iron And Anaemia Guide
 

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Magnesium

RDI: Men- 320mg; Women - 270mg

Functions:

• An essential mineral for overall health of heart, muscles and nervous system
• Works with calcium to maintain strong bones
• Essential for muscle contraction and nerve function
• Helps relax muscle lining breathing passages and lungs
• Helps in glucose metabolism and the release of energy
• Essential in many enzyme systems.

Deficiency: Found more commonly in some patients with hypertension (and those on diuretic drugs), diabetes, migraine, irregular heartbeat, osteoporosis and asthma.

Also found in elderly, dieters, pregnant women, alcohol drinkers, and athletes. Symptoms include nausea, anorexia, vomiting, diarrhoea, irritability, confusion, tremors, loss of coordination.

Note: A magnesium-rich diet may reduce the risk of asthma attacks, abnormal heart rhythm and coronary artery spasm, calcium oxalate kidney stones; and may improve chronic fatigue syndrome.

Good Food Sources
Wholegrains, seafood, soybeans and other legumes, nuts, seeds.

Note: Alcohol increases magnesium loss from body.
 

	Magnesium (mg)
Bread: Wholemeal, 4 slices 100g	90
White, 4 slices, 100g	30
Soya Beans, cooked, 1/2 c. 120g	70
Nuts: Brazil Nuts, 10 nuts, 20g	80
Almonds,12-15 nuts, 20g	60
Cashews, 12 nuts, 20g	50
Peanuts, shelled, 30 nuts, 25g	45
Sustagen Sports, powder, 100g	65
Avocado, 1/2 medium, 150g	45
Banana, 1 medium	40
Bran, wheat, 1Tbsp, 6g	40
Baked Beans, 1/2 cup, 150g	40
Chickpeas, cooked, 60g	40
Salmon/Tuna, canned, 100g	30
Soy Extra (Chemists Own), 250ml	30
Meat, average, cooked, 100g	20
Yoghurt, 200g carton	20

 

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Potassium

RDI: 1950-5460 mg
or 50 - 140 mmol
1 millimole(mmol) = 39mg

Functions: The major mineral element in body cells. Plays an important role in electro-lyte balance, nerve conduction and muscle contraction, beating of the heart, energy production and protein synthesis. Also helps neutralise sodium's tendency to raise blood pressure; may lower risk of death from stroke

Deficiency: More common in persons on diuretic drugs; prolonged vomiting and diarrhoea. Symptoms include muscular weakness, apathy, confusion, abnormal heartbeat.

Toxicity: Rare in healthy people. Over 250 mmol (approx. 10g) may cause cardiac arrest. Toxicity is more likely with kidney, heart or liver disease.

Good Food Sources
Found in all animal and plant cells.
 

Fruit
Apple,150g	150
Avocado, 1/2 med,150g	700
Banana, 1 medium, 150g	350
Orange, 1 medium, 130g	150
Peach, 1 medium, 120g	230
Prunes, 5, 50g	360
Dried Fruit, average, 30g	270
Nuts: Average, 30g	200
Vegetables:
Beans: Green, 1/2 c. 60g	60
Baked Beans, 1/2 c.150g	330
SoyaBeans,cooked,150g	540
Cabbage, raw, 50g	130
Carrots, raw, 50g	110
Boiled, 50g	50
Peas,raw, 1/4 cup, 35g	150
Boiled, 35g	50
Potato: Baked, 120g	660
Boiled, 120g	440
Chips,fried, 120g	660
French Fries, 80g	370
Pumpkin, baked, 100g	300
Tomato, raw, 1 medium	430
Meat:
Average, cooked, 100g	470
Chicken, cooked, 120g	340
Fish, average, cooked, 100g	400
Salmon/Tuna, canned,100g	300
Egg, 1 large	80
Milk: Whole/Skim, 1 cup	370
Soy (e.g. So Good), 1 cup	350
Yoghurt, fruit, 200g ctn	440
Ice Cream, 1 scoop	100
Bread/Cereals/Rice/Pasta:
Bread: White, 4 sl. 100g	90
Brown/Wholemeal, 4 sl.	200
Cornflakes, 1` cup, 30g	40
Muesli, average, 45g	170
Weet-Bix, 2 biscuits	100
Rice, boiled, 1 cup, 160g	70
Spaghetti, ckd, 1c., 150g	80
Miscellaneous:
Chocolate, milk, 50g	200
Butter/Margarine/Oils	Negl.
Negligible Salt: Table	0
Lite Salt, 1/2 tsp. 2.5g	660
Vegemite, 1 tsp, 5g	110

 

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ZINC

 

RDI:	Adults	-12 mg
	Pregnancy	- 16 mg
	Lactating	- 18 mg
	Infants: Breastfed	- 3 mg
	Bottlefed	- 6 mg
	Children:   1-7 yrs   8-11 yrs   12 yrs and over	- 6 mg  - 9 mg  - 12 mg

Functions:

• Essential for tissue growth
• Numerous enzymes require zinc for activity (e.g. enzymes involved in producing DNA genetic material)
• Plays role in structure and function of cell membranes
• Quickens wound healing; may improve healing rate for gastric ulcers
• Boosts immune system
• Required to maintain taste, smell
• Slows progress of 'macular degeneration' eye disorder leading to blindness
• Essential to produce sperm.

Toxicity: Low dose supplementation of 15-50 mg appears safe. Larger doses (over 100 mg) may cause side-effects of nausea, headache, and lowering of 'good' HDL-cholesterol.

Excess zinc can also create a copper deficiency.
Note: If extra zinc taken, supplement with copper in ratio of 1 part copper to 10 parts zinc.
Excess zinc may lessen chromium usage and absorption.

Deficiency: More common in elderly, vegetarians, athletes, dieters. Symptoms include retarded growth, poor appetite, loss/change of taste and smell, mental lethargy, slow wound healing, prone to infections, excessive hair loss, reduced sperm count and ejaculatory fluids, reduced sexual libido.

GOOD FOOD SOURCES
Lean meat, liver, eggs, seafood, brewer's yeast, legumes, whole grains, wheat germ.
 

	Zinc (mg)
Oysters, 6 medium, 30g	19
Beef steak, grilled,120g	6
Lamb, cooked, 120g	5
Scallops, 10 medium, 80g	5
Hamburger w/bun, 170g	3.5
Sausage, grilled, 2 thick, 130g	3
Lobster/Crayfish, 1/2 cup pces, 80g	3
Pork, leg, baked, 2 slices, 90g	2.2
Cashew nuts, 1/4 cup, 40g	2
All-Bran, 1/2 cup, 35g	1.8
Rice, brown, ckd, 1cup	1.5
Sustagen Sport, powder, 100g	1.4
Baked Beans, 1/2 cup, 150g	1.2
Peanuts, 1/4 cup, 40g	1.2
Salmon/Tuna, cnd, 1/2 cup, 100g	1
Soy Extra Drink, 250ml	1
Milk (whole/skim), 1 cup	1
Yoghurt, fruit, 200g ctn	1
Cheese, cheddar, 30g	1
Sunflower Seeds, 1 Tbsp, 16g	1
Fish, ckd, 1 fillet, 120g	0.7
Peanut Butter, 1Tbsp	0.7
Peas, green, 1/2 cup	0.6
Egg, 1 large	0.5
Sweetcorn, 1 cobette, 85g	0.3

Note: Excess fibre can decrease zinc absorption.

Last updated: September 14th, 2007