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“A slice of lemon in my drink? No thanks!”

22 December 2016 - Toxicologist and pharmacologist Jan Tytgat examines the harmful effects of various substances on human beings, food, and the environment. And he takes this knowledge with him when he enters a bar or a restaurant. “I’ll never make a scene about it, but I always frown if I get a drink with a slice of lemon in it.”

22 December 2016 - Toxicologist and pharmacologist Jan Tytgat examines the harmful effects of various substances on human beings, food, and the environment. And he takes this knowledge with him when he enters a bar or a restaurant. “I’ll never make a scene about it, but I always frown if I get a drink with a slice of lemon in it.”
“A slice of lemon in my drink? No thanks!”

© Gudrun Makelberge

The problem is in the peel of the lemon, Tytgat explains. “This peel is a porous sponge that protects the flesh of the fruit from drying out in the dry climate in which lemons grow. Quite a few researchers have been debating how healthy this peel really is. After all, we don’t just put slices of lemon in our drinks: we also use lemon zest as an ingredient in our kitchen. This peel is actually quite healthy, partly because of the ethereal oils it contains.”

Unfortunately, lemon peels also come with quite a few unwanted guests, such as pesticides. “The problem is that the residue of the pesticides is concentrated in your drink, especially in hot beverages such as tea. And pesticides that are absorbed into the body can have a negative impact on the immune system and fertility. Some are even believed to cause cancer. Personally, I would definitely use organic fruit, but even then you can’t be sure. And who asks for an organic slice of lemon in a bar anyway?”

Professor Jan Tytgat
© KU Leuven - Rob Stevens

Traces of animal faeces and urine: another thing you don’t want to ingest. “The faeces of cats, dogs, and foxes in particular can contain parasites such as the dwarf tapeworm. These can lodge in the peel of the fruit these animals come into contact with. That’s why you really need to wash lemons, even the organic ones. You could scrub them with a detergent, but detergents are toxic for your stomach and intestines. Just a thorough rinse with tap water will do the trick.”

And then there is the human factor. “Each lemon is harvested, packaged, sold at the auction, and processed in the bar or restaurant. So the fruit passes through many hands, which may be covered in bacteria or traces of faeces when bartenders don’t wash their hands after using the restroom. As a result, bacterial infections may be passed on, even though a hot drink will kill some of the bacteria.”

“Look, one slice of lemon is not going to make you sick. But why not go for the pragmatic solution? Some countries, including Austria, just give you a small lemon squeezer. This allows you to squeeze the juice into the drink yourself, without the unwanted guests.”

Ilse Frederickx for Campuskrant. Translated by Katrien Bollen.

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