Tuesday, 12 February 2008
And in addition...
After my call for stronger, less hypochondriac, rats Phil asked if I am in favour of additives or not.
There is not an easy answer to that.
First a few ground rules. These are, naturally, from a chemist's perspective.
1. Don't whinge to me that your food is full of chemicals. My response is to ask you what part of your food is not made of chemicals? The term 'chemicals' has been stolen to be used for 'bad' chemicals - pesticides, preservatives etc. But it is misleading as everything is composed of chemicals. What else is there?
2. Similar for the term 'organic'. Excluding things like salt, all food is organic to a chemist. It is a term relating to compounds originating from plants and animals from long before pesticides came on the scene.
Now, to additives proper. These fall into two distinct categories.
1. New compounds that do not occur in nature.
For example, BHT and BHA are added to oils to prevent oxidation and delay rancidity. Are they harmful in small amounts? What are the health effects of the oxidised components of rancid oil? Which is worse?
Synthetic colours. Many are associated with hyperactivity in children but are invariably consumed in association with high sugar products. Which carries the baton for cause and effect? The colour? Or the sugar? Both? Neither?
Margarine is a totally synthetic compound; should it be permitted for human consumption?
2. Compounds that are present in nature.
But not all additives are synthetic. Vanilla, Ascorbic Acid and Benzoic acid all occur in nature but are mass produced cheaply by synthetic processes for addition to food as flavouring, antioxidant/vitamin (C) and preservative respectively. Should nature identical compounds be added to food? If they occur in nature anyway can they be bad? Note that cyanides, strychnine and cocaine are also naturally occurring compounds.
Sulphur dioxide is the most ubiquitous chemical added to our foods. Amongst many uses, it is the preservative present in sausages, dried fruits and wines. It is naturally present in volcanic gases and has been added to foods, by burning sulphur, since Roman times.
Many food additives are plant extracts - carrageenan, for example, is a seaweed extract often used to stabilize ice-cream.
My general view is that if the compounds are needed for the safety of the food, and if they are present at the minimum level for such safety, then they serve a useful function. They should not be present at excessive levels and should not be present if not serving a useful purpose. Sausages, for example, will not last 24hrs without sulphur dioxide.
While I am not convinced that colours at their normally used levels are a problem I do not generally see the need for them at all. Their addition is aesthetic, not functional.
Excessive levels of any compound (chemicals!) will kill you. Vitamin A is toxic. Salt will kill you. Excessive oxygen will kill you. Last year a lady died after drinking too much water. Apple pips contain cyanide. One apple core wont kill you but a guy died after eating a cup full of pips. Another man stir fried potato shoots. Dead.
Too much of anything is bad for you. Moderation is good.
But how much is too much? Good question.
So, my brief answer to the additive question is that in low amounts they are OK but be sensible about them. By and large they are there for a functional purpose.
If someone is complaining about excess 'chemicals' in their food, it is always interesting to ask them if they take vitamin or mineral supplements. It is bizarre how often people who fear small amounts of highly studied additives in their food will consume mega doses of some herbal, mineral or vitamin preparation and assume that it is safe.
On what evidence?