Who can you believe?
Nutrition is a relatively young science.
Vitamin B1 was ‘discovered' less than a
hundred years ago. During the 1930s,
scientists also found that riboflavin (B1),
niacin (B3), pantothenic acid (B5),
pyridoxine (B6) and folate (once known as
B9, but also B10 and B11) were essential for
life. Another B vitamin, biotin, was added in
1942 and vitamin B12 was found in 1948,
although its chemical structure was not
worked out until 1964.
Some of the fatty acids have only been
researched over the last 20 years and we're still
working on some trace elements which are
needed in such tiny quantities that only
sophisticated equipment can detect them.
Over the last 50 years, we've also had an
explosion of food products - from about 600 or
so in the early 1960s to over 30,000 now. With
the increased range of foods, we've had
hundreds of additives that serve a range of
purposes from keeping food safe to making it
possible for us to consume a range of junk.
In spite of the dramatic increase in nutrition
research, we still don't know everything about
food and nutrition. And as happens in various
areas of life, when there's a lack of
understanding, various theories are invented to
fill the void.
This gives rise to lots of myths and much
suspicion - especially about food additives.
I happen to feel strongly against many food
additives, not because I think they're
necessarily harmful, but because they make it
possible for lots of people to consume an
unbalanced diet.
Children wouldn't be attracted to many of the
snack foods, sugary drinks and confectionery
that they now consume instead of fruit, if the
junk foods weren't so brightly coloured. Once
children's palates become accustomed to
sweetness or saltiness, their liking for fresh
healthy products decreases. This is a bigger
problem than the colouring in food products,
although some colourings have recently been
identified as contributing to hyperactivity in
some children.
The Internet has become a mine of mythology
about foods. Each day, my inbox has about 20
emails wanting me to buy some berry extract
that is guaranteed to make me slim, healthy and
younger looking (that one is a bit tempting).
For many years, I've also been getting emails
about the horrors of aspartame, an artificial
sweetener used in low kilojoule drinks and
other food products. The emails alert me to a
‘new' discovery that claims they are the cause
of brain tumours, headaches, multiple sclerosis,
various cancers and even blindness.
I prefer to avoid artificial sweeteners, but there
is no evidence they cause any of these problems
in the quantities that even the greatest consumer
of artificially sweetened products could use.
It's always the dose that makes the poison and
everything - even water - is toxic in excess.
People are growing fatter. Sales of diet colas
are increasing. Is this consequence or
coincidence?
Plenty of studies show that those who decrease
their consumption of sugar, without increasing
something else, lose weight. However, there is
also evidence that artificial sweeteners maintain
a strong liking for sweetened products. We've
all seen someone using a sweetener in their
coffee (saving about 120 kJ) while tucking into
chocolate cake (with about 2000 kJ). Tastebuds
constantly bathed in sweetness crave sweetness.
There's also some evidence from studies with
rats that artificially sweetened foods disrupt
their ability to assess when they're taking in
kilojoules. Rats given artificially sweetened
foods compensate by eating more than normal.
Does this happen in humans? It's feasible.
However, we do know that when the amino
acids that make up aspartame are broken down
in the body, the ‘toxic' chemicals they produce
are in minute quantities and not different from
the breakdown products of the same amino
acids present naturally in foods.
Studies in humans also give differing results
depending on who funded the study. Those
funded by sellers of artificial sweeteners
usually find that people using artificially
sweetened beverages take in fewer kilojoules
and lose weight while studies funded by the
sugar industry claim the sweeteners have no
benefits.
The upshot is that I'd avoid artificially
sweetened foods, but not because of the scare
campaigns. I'd also restrict the quantity of
sugar I consume.
The title of this article is "who can you
believe?" For my part, I am always sceptical
when studies funded by makers of any product
give results favouring that product.
Who can you believe?
In looking at whether we should believe
something, it's also important to remember that
what may appear to be cause and effect may
simply be coincidence.
Before believing anything, I try to find the
original study, check the qualifications of the
researcher and who funds his or her studies as
well as who stands to gain by the results. I then
check that there is a feasible biochemical
mechanism and how it compares with similar
findings from other studies, also noting who
funded them.
For newspaper and internet reports, it's
especially important to check the qualifications
and conflicts of interest. As a medical writer, I
receive lots of media releases and then see them
repeated verbatim in newspapers and magazines
even though they are clearly put out by
someone promoting a product.
In the case of the ‘new' reports about the ‘justdiscovered'
horrors of aspartame, the authors
are usually not listed, or the findings are
attributed to a woman whose name has been
associated with these ‘new' findings for at least
20 years. She has never published any research
in any reputable scientific journal and she's
untraceable.
Often, it pays to check with reputable
organisations, although you also need to check
whether they have financial ties with the
product.