Under The Microscope

EATING SAFELY IN A TOXIC WORLD -- WHAT REALLY IS IN THE FOOD WE EAT, by Sue Kedgley; Penguin, 1998; 324 pp; $24.95

Reviewed by Dr John R L Walker

I got off to bad start with book -- the emotion-charged opening paragraph of Chapter 1 did not inspire my confidence in the author's approach. She starts off talking about "apples stored for months in carbon dioxide gas and ripened with ethylene gas" implying that these are nasty unnatural chemicals yet, as any elementary book on plant physiology will tell you, these are normal products of a fruit's metabolism.

This approach continues throughout Chapter 1, and there is more in this vein on p9 in a paragraph on the imagined evils of controlled atmosphere storage with ethylene as the culprit; never mind the benefits of year-round availability of fresh fruit. Naturally we would all like to pick our fruit straight from the tree but would we all want to slaughter our own chickens or garner our own wheat to ensure freshness?

Our current diet is criticised as a major cause of modern ill-health yet, strangely enough, life expectancy has increased markedly over the past 100 years. The author states that 60% of cancer is caused by diet but gives no references in support. We are told that "irradiated food is zapped with radioactive rays" but fortunately this process is described more correctly later. For me, the last straw was on p20 when the author says "our aim has been to present the information in a balanced and factual way, and we have checked it with the relevant authorities". To me that just didn't ring true, and many of the references cited were inadequate (name and year only) or were from unrefereed sources like newspapers. I would also like to have known something of the contributing authors' academic qualifications.

Having said that, I must also confess to a measure of sympathy with the author's crusade, and the book does draw attention to many problems associated with food in New Zealand, especially aspects of childrens' diet and the pernicious effect of TV advertising thereon.

Chapter 2 covers toxicology whilst in Chapter 3 Dr Tessa Jones summarises how our bodies attempt to cope with toxins; unfortunately some of the biochemistry and physiology cited is not strictly correct (e.g. phenylpyruvic acid, not aspartame accumulates in PKU disease). Similar errors occur in Chapter 5 on food additives; thaumatin is not artificial and is a protein produced by the tropical plant Thaumatococcus danielli (therefore "organic"?) whilst the description of the metabolism of aspartame and its component amino acids is biochemically inaccurate.

Other chapters cover various types of foods and their problems, real or hypothetical whilst the "hot" topics of genetically engineered and irradiated foods are considered in Chapters 8 and 9. The chapters on food poisoning and food labelling were rather better and quite informative, and chapters 12 and 13 extol the virtues of so-called "organic foods". In addition there is a Glossary (with too many sloppy definitions) and several appendices.

I have no quarrel with the overall concept of this book and I am sure that the authors are driven by the highest of motives, but there are far too many inaccuracies and loose unsubstantiated statements for me to be able to recommend it as a reliable reference.

Dr John R L Walker recently retired as Associate Professor of Biochemistry at the University of Canterbury