Protein
Obtaining
adequate protein on a vegan diet is not a problem. Nuts & seeds,
pulses, wholegrain and grain products and soya products all supply protein.
Previously, it has been thought that plant proteins are of a lower quality
than animal proteins in terms of their essential amino acid content.
However, this is no longer regarded as a problem and eating a balanced
diet of plant
foods will provide all the essential amino acids in adequate amounts.
Essential Fatty Acids
There are two essential fatty acids which must be supplied by the
diet. These are linoleic acid and a-linolenic acid. Essential fatty acids
are important for cell membrane function, cholesterol metabolism and the
synthesis of various metabolites. Good sources of essential fatty acids
are vegetable oils. It is important to have the correct balance between
linoleic acid and a-linolenic acid. It has been suggested that vegans should
use soyabean or rapeseed oils rather than sunflower or corn oils as these
help give a better dietary balance.
Vitamin B2 (Riboflavin)
Certain studies have found vegans to have a low intake of the vitamin,
riboflavin. Riboflavin is important in converting protein, fats and carbohydrates
into energy, and the synthesis and repair of body tissues. Good sources
of riboflavin include whole grains, mushrooms, almonds, leafy green vegetables
and yeast extracts.
Vitamin B12
Vitamin B12 is found primarily in meat, dairy products and eggs and
is absent from plant foods. Considerable research has been carried out
into possible plant sources of B12. Fermented soya products, seaweeds and
algae such as spirulina have all been proposed as containing significant
amounts of B12. However, the present consensus is that any B12 present
in plant foods is likely to be in a form unavailable to humans and so these
foods should not be relied upon as safe sources.
Vitamin B12 is important in the formation of red blood cells and the
maintenence of a healthy nervous system. When deficiency does occur it
is more likely to be due to a failure to absorb B12 from the intestine
than a dietary deficiency.
Vegans can obtain B12 from a wide range of foods which have been fortified
with the vitamin. These include certain yeast extracts, veggieburger
mixes, breakfast cereals, vegetable margarines and soya milks. You should
check the packaging to see which individual products are fortified with
B12.
Vitamin D
Vitamin D is present in oily fish, eggs and dairy products in variable
amounts. It is not found in plant foods. However, vegans can obtain vitamin
D from vegetable margarines, some soya milks and certain other foods which
are fortified with the vitamin.
Vitamin D is also synthesised by the skin when exposed to sunlight.
Synthesis of vitamin D in this way is usually adequate to supply all
the body's requirements. Most vegans will obtain sufficient vitamin D
providing they spend time outdoors on bright days. Fortified foods further
ensure adequate amounts.
Vegans who may be confined indoors may be recommended a vitamin D supplement.
Also, infants who are seldom oudoors or who are dark-skinned may require
supplements. Asian vegans may also be at risk of deficiency, particularly
Asian women who may be required to keep their skin covered for cultural
reasons.
Calcium
The major source of calcium in British diets is generally milk and
dairy products. Vegans can obtain adequate calcium from plant foods. Good
sources include tofu, leafy green vegetables, watercress, dried fruit,
seeds and nuts. Also, white bread is fortified with calcium, as are some
soya milks. Hard water can also provide significant amounts of calcium.
Iodine
Milk is the primary source of iodine in the British diet and studies
have indicated some vegans may have a low iodine intake. Seaweeds are a
good source of iodine, and vegetables and grains can contain iodine depending
on the amounts in the soil.
Infants
It is perfectly possible to bring up a child on a vegan diet. Vegan
children should be given plenty of nutrient rich foods and need good sources
of protein, calcium, vitamin B12 and vitamin D. High fibre foods can fill
up a child without filling their nutritional needs as well as interfering
with mineral absorption from the intestine. For these reasons, foods high
in fibre shouldn't be overused.
Vegan Storecupboard
Dairy products can largely be replaced with various soya products.
There are several brands of soya milk. It can be purchased either sweetened
or unsweetened, plain or flavoured. Different brands may be fortified with
vitamin B12, vitamin D and calcium.
Soya cheeses, yoghurts and cream are all available from health food
stores. Eggs can be replaced in recipes by commercial egg replacer products,
also available from health food stores.
The Vegan Society's Animal-Free Shopper is a useful guide for vegan
shoppers and includes suitable cosmetics, supplements, clothing and various
household goods as well as food products.
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