THE RECOMMENDED daily allowance
(RDA) of foods and supplements has traditionally been set by
government health bodies in the USA, UK, and Europe. In the USA,
RDA stands for "Recommended Daily Dietary Allowance, which
is established for each vitamin and mineral by the Food and
Nutritional Board of the National Academy of Sciences and the
Food and Drug Administration (FDA). The US figures quoted here
are from the FDA. In the UK the Department of Health gave the RDA
for vitamins A, C, and D, three of the B vitamins, and three
minerals in 1979. However, in 1993 the European Union - (EU)
issued a directive on food labelling for its members, which
included RDAs for twelve vitamins and six minerals. As a result,
UK food labels are being revised to include the EU
recommendations, although it may be some time before they appear.
In addition, the government
of the UK issued a report in 1991 suggesting new guidelines for
daily requirements of vitamins and minerals, which would replace
the RDAs. These are called, collectively, Dietary Reference
Values (DRVs), and consist of these terms:
Estimated Average Requirement (EAR), which should meet the requirements of half of the population.
Reference Nutrient Intake (KNI), which replaces the former RDA, is meant to represent the nutrient requirements of some 97 percent of the population. The amount recommended is higher than most people actually need. The EAR meets the requirements of half of the population; of the remaining half some need more and some need less than the EAR.
Lower Reference Nutrient Intake
(LRNI)
Is the nutritional
requirement for those whose needs are low Most people will need
more than this amount in order to maintain their health. Anyone
who is getting less than the LRNI might be in danger of
nutritional deficiency.
Daily Intake
The following list describes
those vitamins and minerals that should be present in the daily
diet. The descriptions include the RDAs P for the USA, UK, and
the EU. The amounts given are those that should be taken to
prevent a vitamin or mineral deficiency, not those needed to
improve health or prevent non-deficiency diseases.
[Vitamin A] [Vitamin B1] [Vitamin
B2] [Vitamin B3] [Vitamin B5] [Vitamin
B6] [Vitamin B9] [Vitamin B12]
[Vitamin BIOTIN] [Vitamin
C] [Vitamin D] [Vitamin E] [Mineral CALCIUM]
[Mineral IRON]
[Mineral IODINE] [Mineral MAGNESIUM]
[Mineral
PHOSPHORUS] [Mineral ZINC]
VITAMIN A
is necessary for healthy skin and the ability to see in poor
light conditions. The body manufactures vitamin A (retinol) from
plants containing beta-carotene, but vitamin A is directly
available from a few animal foods (e.g., liver and some fish).
This vitamin is fat-soluble.'
RDA is: 5000 iu2 (US); 750µg3
(UK); 800µg (EU).
VITAMIN B1
thiamine is necessary for healing and maintaining the nervous
system and for the metabolism of carbohydrates. This vitamin is
water-soluble.
RDA is: .2.1.5mg (US);1.2mg (UK);1.4mg (EU).
VITAMIN B2
riboflavin is required for metabolising foods, manufacturing and
repairing tissues, and maintaining healthy mucous membranes. This
vitamin is water-soluble.
RDA is: 1.7mg (US); none current (UK); 6mg (EU).
VITAMIN B3
niacin belongs to the vitamin B complex. It is necessary for the
efficient functioning of the digestive and nervous systems. It
also helps in metabolising foods. This vitamin is water-soluble.
RDA is: 1.3-1.8mg (US); none current(UK); 8mg (EU).
VITAMIN B5
pantothenic acid is needed to release energy from fats and other
foods, and to promote normal growth and development. This vitamin
is water-soluble.
RDA is: 4.7mg (US) (new figures give 10mg); none current (UK);
6mg (EU).
VITAMIN B6
pyridoxine is necessary for metabolising the amino acids in
proteins, the formation of antibodies and red blood cells, and
for maintaining a healthy digestive and nervous system. This
vitamin is water-soluble.
RDA is: Zmg (US); none current (UK); 2mg (EU).
VITAMIN B9
folic acid is necessary for maintaining the digestive and nervous
systems and works with B12 in the formation of red blood cells
and genetic material. This vitamin is water-soluble.
RDA is: 4OOµg (US); 200µg (UK); 3OOµg (EU).
VITAMIN B12
is necessary for maintaining the nervous system, red blood
formation, cell division during growth, and the development of
genetic material. This vitamin is water-soluble.
RDA is: 3µg (US); 1µg (UK); 2µg (EU).
BIOTIN
is necessary for energy release from fats. It is water-soluble.
RDA is: 300µg (US); none current (UK); 0.l5mg (EU).
VITAMIN C
ascorbic acid is required for healthy skin, teeth, gums, and
blood vessels. It assists in the absorption of iron, in healing
wounds and broken bones, and is necessary for the prevention of
scurvy This vitamin is water-soluble. RDA is: 6Omg (US); 3Omg
(UK); EOmg (EU).
VITAMIN D
is required for the absorption of calcium and phosphorus. This
vitamin is fat-soluble.
RDA is: 4OOiu (US); 2.5µg (UK); 5µg (EU).
VITAMIN E
helps to protect body tissues and is important for the prevention
of anemia, although the precise role that this vitamin plays in
the body is not clear. This vitamin is fat-soluble.
RDA is: lOmg (US); none current (UK); lOmg (EU).
CALCIUM
is needed for the growth and development of healthy bones and
teeth.
RDA is: 8OOmg (US); 5OOmg (UK); SOOmg (EU).
IRON
is vital for the formation of the oxygen-carrying red blood
cells.
RDA is: 10-30mg/18mg for pregnant women (US); 12 mg (UK); l4mg
(EU).
IODINE
is necessary for regulating the thyroid gland.
RDA is: 150µg (US); l40µg (UK); 150µg (EU).
MAGNESIUM
is necessary for strong bones, the release of energy from food,
and the transmission of nerve impulses and muscular movements.
RDA is: 350mg (US); none current (UK); 3OOmg (EU).
PHOSPHORUS
is required for maintaining body functions, the production of
energy, and, with calcium and magnesium, the maintenance of
healthy teeth and bones.
RDA is: 30D-400mg (US); none current (UK); 800mg (EU).
ZINC
helps to develop a healthy immune system and is necessary for
growth and development, including that of the reproductive
system.
The RDA is: l5mg (US); none current (UK); l5mg (EU).
The most palatable way to
get your daily vitamin and mineral requirement is to eat a
balanced nutritious diet.