In 1879, a chemist named Constantin Fahlberg sat down to dinner without washing his hands after a day spent handling coal tar. His bread tasted strangely sweet. So he went back to the lab and started tasting everything on his bench until he found the source. That was saccharin, the first artificial sweetener, discovered because a man would not wash his hands before dinner. Nearly 150 years later, we are still arguing about whether the stuff is going to kill us.

This week, Zoë and Kylee dig into the question every diet-soda lover has had to defend at a gas station: are artificial sweeteners actually bad for you? They trace how a coal-tar accident became a billion-dollar industry, why the WHO's "possibly carcinogenic" label on aspartame puts it in the same risk tier as pickled vegetables and working as a carpenter, and how Donald Rumsfeld personally muscled aspartame through the FDA. The saccharin cancer scare that haunted a generation came from male rats dosed with the equivalent of hundreds of sodas a day, through a mechanism human bodies do not even have.

Along the way: the wartime rationing that built the sweetener industry, the cyclamate the US banned and never reinstated while the rest of the world kept drinking it, the every-fifteen-years villain cycle that has run through fat, high-fructose corn syrup, gluten, and seed oils, the genuinely fascinating Suez microbiome research where scientists grew human gut bacteria in mice, the stevia-in-a-petri-dish problem, and the erythritol heart-attack headline that fell apart the moment anyone read the study.

Plus: why these things were always sold to women as a permission structure, the one category athletes actually need to watch (sugar alcohols, and the osmotic chaos they bring to a long run), the client drinking ten Liquid IVs a day, and a hot-takes round that settles Diet Coke versus Coke Zero once and for all.

Listen for the full story.

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Resources, citations, and studies discussed in this episode are available at yourdietsuckspodcast.com.