A 79 year old German has passed away after eating a homegrown zucchini. The vegetable most likely continued to grow into a self-made poison. This usually does not happen anymore, but it does come up sometimes in very rare cases. The man and his wife were very sick for two weeks after eating the zucchini, and they were taken to hospital. The woman recovered, but the man's health continued to deteriorate and he eventually died.
The culprit is the substance cucurbitacin. This substance used to occur naturally in zucchinis and cucumbers to prevent animals from eating the vegetables. Over the past few centuries growers have managed to remove the substance through breeding programs. But if people grow their own vegetables, the substance can crop up. Therefore, it is advised to first eat a piece of raw zucchini if you are growing it yourself. If the vegetable tastes much more bitter than usual, this may indicate cucurbitacin. This also applies to pumpkins.