Lisa Markwell: Spare me the meat-free Mondays

Thanks to Sir Paul, I'll struggle with my daughter's packed lunch

Did you do it? Have a meat-free Monday, that is. Did the sight and sound of Paul McCartney extolling vegetarianism once a week – for the sake of the planet – make you put down your pasty?

It's difficult to argue with the man's logic, although the image of belching and farting cows does bring out the schoolchild in me. These bovine digestion byproducts are causing greenhouse gas emissions, and the more burgers and steaks we consume, the worse it gets. That's enough to stop the childish tittering.

Meat-Free Monday is endorsed by a plethora of celebrities, from Giorgio Locatelli and sainted Joanna Lumley – to those with less than, well, beacon status (hello Kelly Osbourne). For smart restaurants and respected chefs to suggest veggie dishes for occasional use by us committed carnivores is a good thing – God knows, my mind goes blank when non meat-eaters come round for dinner. If I can't make asparagus tagliatelle I'm all out of ideas.

But still... I wonder, why can't we just cut out the beef? Now that tuna's officially A Bad Thing, I'll struggle to put something in my daughter's packed lunch that isn't her favourite, roast chicken, or second favourite, "round ham". She doesn't like cheese, or hummus. We've been known to home-make sausage rolls – the only way to guarantee a quality snack without acres of lard and mechanically recovered yuk – because having them in the lunchbox is an incentive for a good morning in the classroom. Children are creatures of habit, more so, even, than the office drones who have a prawn sandwich and a diet Coke every weekday for years, nay decades.

Meanwhile, like many folk who've had a touch of cancer, I've embraced the medical reasons for cutting back on red meat and exchanged beef for turkey when it comes to meatballs – the Ottolenghi recipe comes with my ringing endorsement, and I say that as a foodie who usually loathes low-fat, sugar-free, goody-goody versions of anything. But according to Sir Paul, that won't do – I must be completely meat-free on a Monday. I know, I know, it's only one day a week but do turkeys and chicken really expel enough methane to worry the climate-change crew?

Having said that, I did do meat-free Monday yesterday – not because I'm a sucker for a bandwagon, more out of curiosity – and it was without any great hardship, but at a price. Finding something substantial, which means protein, for lunch that's not either endangered (does satisfying Sir Paul mean pissing off Greta Scacchi?) or rumoured to be riddled with toxins is not easy. It requires a visit to an upmarket, organic grocery for sustainably-fished sardines – not an option that's available to everyone. And please don't even think about suggesting tofu.

By all means, let's stop buying McDonalds burgers and do as much as we can to stop the deforestation of south America to provide grazing for these poor benighted beasts. I don't mind having a beef-free bonanza. Hey, let's do seven out of seven days. But don't make sane omnivores who like a nice organic chicken risotto or locally-sourced slow-cooked shoulder of lamb do without if it's what we really crave. We promise not to cook the roast potatoes in beef dripping, honest.

l.markwell@independent.co.uk