If you’re used to counting your five portions of fruit and veg every day, it could be time to consider adjusting your habits. Research suggests variety is key – and quite a lot of variety at that. Sue Quinn unpeels the truth
Forget five a day…
We’re all familiar with the five-a-day rule. It refers, of course, to the number of recommended 80g servings of fruit and vegetables you should consume daily for optimum health. But growing numbers of nutritional experts now believe there’s a better target to aim for when it comes to eating enough of the good stuff.
They’re recommending we try to eat 30 different plant foods each week in order to keep our gut microbiome in tip-top shape. That’s the complex system of trillions of microbes in our gut that profoundly influence our physical and mental health.
The magic number 30 stems from a 2018 study by the American Gut Project (initiated by scientists at the University of California San Diego), which also involved participants from Australia, the UK and 42 other countries.
“By looking at the microbiomes of tens of thousands of volunteers, we saw that people who eat around 30 different plants every week have much greater microbial diversity than those who eat just 10,” says Professor Tim Spector, a nutrition expert at King’s College London, who was involved in the study (with the British Gut Project). “Conducting this research has totally changed the way I approach my diet and, in turn, my health,” he says.
But hold on: most people in Britain can’t manage to eat their five-a-day, so isn’t 30 way too ambitious? Prof Spector says no: “It’s not as hard as you think, when you realise plant foods include nuts, seeds, grains, herbs and spices, as well as the more obvious fruit and veg.”
OKAY, SO WHAT ARE THE BENEFITS EXACTLY?
It’s now widely accepted that the greater the diversity of microbes in our gut, the better it is for our overall health. Of course, gut diversity is affected by many lifestyle factors: our genes, our environment, the amount of sleep we get and our age are among the things that play a part. But what we eat obviously has a significant influence on our gut health, too.
It’s thought fibre probably plays an important role in this. Eating a wide range of plant foods – many of which are rich in fibre – can help to create the ideal nourishing environment for lots of good bugs to flourish in our gut.
The problem is, many of us reach for the same fruit and veg on repeat, says Jennifer Medhurst, registered nutritionist and author of new book The Imperfect Nutritionist (Kyle Books £25), a down-
