I see the guidelines on fruit and veg are to be changed again - gone are the days when people could be healthy eating a meagre five 80g portions of fruit and veg, and instead the new requirement is for ten 80g portions per day. Presumably, as soon as the new guideline comes in, everyone who was previously healthy will immediately drop dead. Or something.
Seriously, though, this is a bad change, and will probably be counter-productive.
The thing is, as I've mentioned before, five-a-day was always a largely arbitrary target, chosen because it was easy to remember. The underlying message was really "you should probably eat more fruit and veg." And, in that vein, five-a-day was a really good guideline - as well as being easy to remember, it had the advantage of feeling easily achievable. After all, three-a-day is pretty trivial (fruit juice with breakfast, a banana with lunch, and some sort of veg with dinner), so moving to five doesn't feel like much of a stretch. And that meant that most people could at least aspire to getting there most of the time, and if they fell short it probably wasn't by too much.
But getting to ten-a-day is a much tougher target, which means that people who were just about getting to five will find themselves falling well short of ten. And when faced with a target that is not just tough but well out of reach, a lot of people are likely to just give up entirely. (If the target is five and I manage four, maybe I'll try harder. If the target is ten and I manage four, why bother?)
The other thing to consider, though - and this applies to most of the health advice/warnings that we are given - is that the potential benefits and risks are invariably very small. Sure, moving from five-a-day to ten-a-day might reduce your risk of heart disease and some cancers... but only by a very very small amount. To the extent that there's almost certainly something that will make a much bigger impact:
- If you're a smoker, you should really stop.
- If you're a heavy drinker, you should cut down.
- If you're part of the 50%+ who are either overweight or obese, you should seek to lose some of that excess weight. (Which, usefully, will almost certainly entail improving your diet and exercising more, giving a triple benefit.)
- Once you've tackled those three, the next biggest issue is probably air pollution - so look to moving out of the city and/or reducing your commute. (Unfortunately, those two goals are probably at odds!)
That's neither a perfect list nor is it an exhaustive one. But I'd wager that an awful lot of people have something on that list that they could stand to improve - and improving that will make much more difference than getting to ten-a-day (or, actually, even five).
Until the big things are sorted, the sorts of micro-benefits and -risks that are now being talked about can be ignored. And if you're in a position where you have sorted out all the big stuff, you're in a sufficiently good position that the stress from worrying about these micro-risks is probably more dangerous than the micro-risks themselves.