Eating lots of fruit and vegetables could be bad for your health, says Joanna Blythman

In it, an international team of researchers reports the outcome of an illuminating diet trial.

For two weeks, they put 27 students who normally ate a typical Anglo-American diet, top-heavy with highly processed food, on a theoretically more healthy ‘Mediterranean diet', one with a higher proportion of fresh fruit and vegetables than they would normally eat.

Half the group ate organically-grown food, half ate the conventional, pesticide-grown equivalent.

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Researchers then tested the participants’ urine for traces of plant growth regulators, synthetic herbicides like glyphosate, various types of insecticides and fungicides.

The results were graphic.

Those students who ate a ‘Mediterranean diet’ consisting of conventionally-grown food ended up with three times more pesticide in their urine than they had when they were munching away on their habitual bad old processed food diet.

Meanwhile, the students who were eating the same foods, only organically-grown, had 91% less pesticide in their pee than their peers on the non-organic diet.

I’m not surprised by this finding. Many of us have been promoting the pesticide-avoidance benefits of organic farming for decades only to be frustrated by government apathy.

Year in, year out, annual UK government pesticide residue statistics show that fruit and vegetables contain considerably higher levels of pesticide residues than any other category of food.

Yet government healthy eating advice neither recommends that we should favour organically-grown fruit and veg, nor acknowledges any hazard to our health from pesticides.

People who raise this thorny topic are told to pipe down. Other health benefits of a fruit and veg-heavy diet, such as their high fibre content, more than compensate for any pesticide risk, they say.

We mustn’t put people off eating fruit and vegetables, must we?

But following this new research such airy reassurance rings hollow.

You’ll always find me dissing ultra-processed food but if I had to find one mitigating argument in its favour it is that industrial processing does have the effect of diminishing any chemical pesticide residues that were present in the ingredients to start with.

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In pesticide poison terms, a pappy white loaf, stripped of almost all its nutrients because these have been removed by milling, might be a safer, healthier option than a supposedly healthy wholegrain loaf made from chemically-grown flour.

If limiting your children's pesticide exposure is a prime concern, you’d be wiser to feed them cornflakes that are almost as heavily processed as the box they come in than encourage your offspring to eat grapes, strawberries, and other conventionally-grown produce that is notorious for containing the worst levels of pesticides.

I could write a book explaining everything that is bad about potato crisps – the corrupted oils, the battery of additives, the hidden ‘processing' aids, the chemical flavourings – but pesticide traces are usually obliterated by their utterly industrial production method.

Your ‘healthy’ jacket potato, on the other hand, will contain residues, possibly of multiple pesticides, both systemically – in its flesh that is – and very likely on its surface also.

So it’s really not good enough to keep trotting out the Five-a-Day mantra if you don’t at the same time encourage people to eat organic food, preach the benefits of this more enlightened food production method to the general public, and assist its expansion.

If the UK government was as supportive of organic farming as it is of risky genetic engineering, now dubbed ‘gene editing’, touted by the likes of Owen Paterson and his bio-tech cronies, then our health would quickly benefit.

Of course, that Five-a-Day slogan was always bogus. The term itself was adopted in 1991 as a marketing slogan at a meeting of fruit and veg companies in California.

Brilliant for avocado sales, for sure, but it isn’t predicated on sound science.

Back in the day when my understanding of these issues was more limited and I too evangelised the elevated healing capacity of fruit and vegetables over other foods, I was forever being challenged by elderly men who had reached a fair and reasonably healthy old age, yet had never let a cube of pineapple nor a leaf of lettuce past their lips.

“I never ate that stuff, lassie, and I’m no gonnae start.”

Belatedly, I see their point.

In a traditional Scottish diet, fruit and vegetables were only ever a minor element. Until the 1980s, when people were much slimmer than they now are, we depended on local staples like leeks, carrots, onions, and heaps of starchy spuds.

Fruit was limited. Berries made an appearance in the summer, rhubarb – the green-red garden variety, turned up in jam and tarts. Sour apples were eaten heavily sweetened in pastry.

But now from Scrabster to Selkirk we’re loading up on expensive fruit and veg, grown with the heavy use of chemical fertilisers and pesticides, all derived from fossil fuels, and shipped from the ends of the earth.

Just have a quick glance around you as obesity and diet-related diseases like cancer soar, and consider for a minute if our diet of pesticides – known poisons and hormone-disruptors – might just be an enquiry line for investigating what has gone so terribly wrong with the way we eat.

As Dr Chris Seal, one of the authors of the study puts it: “While it is a common refrain among many well-intentioned health groups that one should eat more fruits and vegetables, no matter whether organic or conventional, the present study shows that this recommendation requires further scrutiny.

"Trading off one health risk for another becomes a dangerous game when organic options that effectively eliminate these risks exist.”

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