The World Cancer Research Fund report must not be dismissed as alarmism. It should prompt more study into what goes into our food

Isaw Professor Sir Michael Marmot, chair of the World Cancer Research Fund's review into the causes of cancer, being interviewed by Jon Snow on Channel 4 News.

He came across as a well-informed, reasonable man who would enjoy a nice piece of meat occasionally, no doubt washed down by a decent glass or two of wine, not some fear-ridden, puritanical vegan on a mission to spoil all our fun.

I suspect Professor Marmot and his WCRF colleagues were well prepared for the 'bunch of killjoys - what can we eat?' reaction they unleashed. But if ever there were a case of shooting the messenger, a demonstration of the resistance British people have to taking personal responsibility for their health, then this was it.

I don't find WCRF's recommendations that outlandish. It recommends that we eat no more than 750 grams of meat a week. That's quite a generous amount in my book. It sends out warning shots about bacon. No huge surprise here - the nitrate preservatives in bacon are known not to be beneficial for human health and only permitted as a trade-off against food poisoning. Then there is all the uncontroversial stuff about eating more fruit and vegetables, exercising more and drinking in moderation.

There is, however, one glaring omission in the WCRF's deliberations. It draws no distinction between different qualities of food in the same generic category.

Call me old-fashioned, but I can't see how a little bit of dry cured, organic bacon from free-range pigs that contains the minimum of preservative will affect the body in the same way as the watery stuff laden with chemical additives.

It simply doesn't make sense to treat extensively reared, grass-fed beef the same as beef from animals kept in a shed and fattened up on barley.

It never fails to amaze me just how different the ingredients for foods bearing the same name can be.

The sausages I buy from the farmers market contain 90% pork and the rest is rusk and seasonings with just one preservative, but the list of obscure chemical ingredients on most supermarket sausages runs to a paragraph.

Never before in human history have we been exposed to such a cocktail of synthetic chemicals in our diet. Common sense suggests this must have some bearing on the current plague of cancers. Public money should be spent on investigating this - urgently.n

Joanna Blythman is the author of Bad Food Britain