John_Yudkin_-_Pure_White_and_Deadly_revised_1986_OCR

Pure, White and Deadly
sically harmless; you can make yourself dangerously ill by taking
large quantities of water. No substance is intrinsically harmful; it
was fashionable in the early part of this century to give medicines
containing arsenic as a tonic, although of course the quantities were
very small indeed.
Similarly, if it turns out that cyclamate, or saccharin, or anything
else, causes some undesirable effect in daily amounts that are fifty
or one hundred times as much as anyone could possibly take - and
even then only when taken over a period of ten years or more - it
would not be sensible to ban it automatically.
In the USA the situation was complicated by what is known as
the Delaney Clause, agreed by the US Senate in 1958, which says
that 'no additive shall be deemed safe if it is found to induce cancer
when ingested by man or animal'. This has been interpreted as
forbidding the use as a food additive of any substance that, in any
quantity, and over however long a period, produces cancer in any
species of animal. It was this provision that led to the banning of
cyclamate in the USA in 1970. This decision was based on the result
of one experiment in which a small proportion of rats fed for a long
time with very large doses of a mixture of cyclamate and saccharin
developed cancer of the bladder. Within a week or two of the American
decision, the UK followed its example, so that cyclamate is not
used by the food industry in either country, although the position
is under review. However, 16 out of the 17 countries of Western
Europe do permit the use of cyclamate.
Those people who are still concerned about the possible hazards
of taking artificial sweeteners could reduce or abolish their cause for
worry by using mixed sweeteners. This should reduce the possibility
of being harmed by anyone of them, since each would be present
in a lower concentration than if it were the sole sweetening agent.
Not only sugar is sweet
At present, the better-known non-caloric sweeteners permitted in
one or more of the countries that control food additives are saccharin,
cyclamate, aspartame, acesulfame-K and thaumatin (talin).
Their relative sweetness compared with sugar is given in the table.
For a variety of reasons, however, these figures are only approximate.
First, people's subjective assessment of sweetness varies.
Second, the intensity of some sweeteners increases or decreases with
the acidity of the food or drink to which they are added. Third,
sometimes their relative sweetness changes with the degree of their
dilution and the temperature of the food or drink.
The non-caloric sweeteners are not entirely interchangeable. For
example, saccharin and, to a lesser extent, aspartame are not stable
to heat, so they are not used in the preparation of dishes that require
prolonged cooking.
In addition aspartame, being a compound of two amino-acids,
aspartic acid and phenylalanine, may cause upset in children born
with the condition of phenylketonuria (PK U). Such children are
unable to deal with more than a sxnall quantity at a time of phenylalanine,
one of the amino-acids found in most proteins. If more than
this limited amount is taken regularly, a substance is produced that
can cause mental impairment. Children usually grow out of PKU
by the age of 10 years or so. Meanwhile the condition is controlled
by giving the sufferer a carefully constructed diet containing sorts
and quantities of protein that enable the phenylalanine intake to be
limited. In addition, a child with PKU should be made aware of
which soft drinks are sweetened with aspartame, and be taught to
avoid these.
Relative sweetness of sweetening agents
(Threshold sweetness of sucrose = /·0)
Caloric sweeteners Non-caloric sweeteners
Glucose 0·5 Cyclamate 30
Sorbitol 0·5 Acesulfame-K ISO
Mannitol 0·7 Aspartame 200
Xylitol 1·0 Saccharin 300
Fructose 17 Thaumatin 3,000
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