In a highly personal piece, a dad in his mid-50s asks why he shouldn't carry on enjoying the occasional spliff

So it's official: the over-fifties are still enjoying a purple haze. Researchers say illegal drug use is on the up among my generation of ex-hippies: we're still rolling joints or snorting the odd line, four decades on.

Londoners are the most likely to have a puff – almost one in 10. And if you're over 50, but under 65, the odds are even higher. Being a 55-year-old from Muswell Hill, north London, I am guilty on both charges. I started smoking weed at university, after going to see the Grateful Dead at the Rainbow Theatre in 1981, and have carried on almost ever since.

After uni I had to hide it from my parents. Then my wife and I had to hide it from the kids. Now the kids have flown the nest, and we don't have to hide it from anyone. We smoked more often back then; nowadays, it's no more than once or twice a week, maybe at the end of a dinner party, or to help us get to sleep.

We have friends who grow their own, which is reasonably tame, but much of the stuff you can buy these days is far too strong. Most of our friends have given up cigarettes, but pass round a joint and most people will have a toot. I haven't known it lead on to debauchery or crack addiction, but I wouldn't want anyone to think I'm advocating drug use, particularly among the vulnerable and impressionable. I suppose it is simply that, having reached my mid-fifties, conceitedly or not, I think I have a goodish idea of what will do me harm and what to avoid.

Not many people in their fifties are into dance drugs and clubbing, but we do go with friends or even with the kids to festivals, where party pills make the whole experience a lot more fun. If I was to get on a soap box, I'd say that the meow meow (mephedrone) that was popular and legal a few years back was great fun, and except for a couple of highly publicised incidents, did very little harm. It was a disappointment the Government didn't leave it legal, instead of which hundreds of thousands of people end up doing things like ketamine that are illegal and less fun.

Buying good-quality drugs that are not too strong is always a problem. I don't see why there shouldn't be a dispensation for the over-fifties to buy weed from their pharmacist. Something for the weekend, sir? Yes please: an ounce of weed, a couple of Viagra and a pack of Sanatogen. Bliss!