A few years ago dozens of restaurants in China were caught seasoning their dishes with ground poppy.

The cooks were mixing the powder, containing low doses of opiates – codeine and morphine – into their soups and seafood dishes.

But why? They hoped that their customers would keep coming back for the ‘addictive’ taste. Whether that actually happened, or whether it’s even possible to get people addicted to such small amounts, is still unclear.

Incidentally, you too probably sometimes eat opiates without knowing. Dried poppy seeds also contain traces of the same substances found in opioids.

The Dutch call those seeds ‘maanzaad’, moonseed. And a couple of tasty moon-seed buns can even result in testing positive for drugs. But don’t panic: if you wanted to get high on moonseed, you’d have to eat several kilos of it.