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How an Artificial Sweetener May Have Destroyed the Roman Empire
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Apr 4, 2025
Ancient Rome was the greatest empire in the world - until it collapsed. Did lead exposure doom the empire? Recent research uncovered high levels of lead in Imperial Rome's drinking water, but that wasn't the most dangerous source of lead in the ancient civilization.
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Ancient Rome was the greatest power of its era
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and one of the most spectacularly impressive empires in history. But then one day, it all collapsed
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While no one knows exactly why the empire disappeared into history, at least one researcher
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has proposed that the culprit might be something as simple as lead exposure
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And while recent studies have uncovered high levels of lead in imperial Rome's drinking water
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the real danger might have been an artificial sweetener. Today, we're going to take a look at how Roman aristocrats might have poisoned themselves
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with artificial sweetener and destroyed the whole empire in the process. The Roman Empire had an incredible amount of wealth, and like pretty much all rich people
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wealthy Romans loved to throw a good feast. Showing off one's bankroll by hosting elaborate dinner parties was basically a standard operating
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procedure for the Romans. Another was to sweeten the food with a thick grape syrup called sapa
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The flavoring was made by boiling and skinning grapes, then mashing them through a sieve and mixing the paste with sugar
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Sounds pretty yummy, right? Well, the problem is that Romans would cook the sapa in lead pots
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The lead would then mix into the syrup, making it toxic. So while the sapa made the wealthy Romans' food taste better
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it was also slowly poisoning them. Bittersweet indeed. Sapa may have been toxic, but the Romans loved it
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and used it for more than just sweetening foods. It was also used extensively in winemaking
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Sapa was used to preserve wine, which had the unfortunate side effect of infusing the wine
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with poisonous lead. The Romans, much like a real housewife of Beverly Hills
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had a large appetite for wine. The average Roman drank a liter of this stuff each day
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which adds up to around 100 gallons of wine a year. That is a lot of lead
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and we're just talking about the average Roman. Elite Romans drank even more heavily
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For example, the emperor Elagabulous was rumored to literally drink from a swimming pool full of wine
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Not going to invite him to my next party. Romans used sapa as a sweetener because it worked
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The flavor does make wine and food taste better. But today we know that the syrup was toxic
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Modern science has determined that due to being made in lead pots, the mixture contained a compound called lead acetate, also known as sugar of lead
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We probably shouldn't take something so deadly and name it something that sounds so sweet
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Downing as much lead acetate as the Romans did is not healthy. The side effects of the poisoning include dementia, infertility
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and eventually complete organ shutdown which is pretty bad because you know your organs are important In the 1980s research scientist Jerome Regu recreated sapa using ancient recipes that detailed
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the methods the Romans used to make the artificial sweetener. His results confirmed what he had long
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suspected, that the sapa turned out to contain a dangerous concentration of lead. Quantities
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ranged from 240 to 1,000 milligrams of lead per liter. That's way more lead than I like in my liter
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Neregu explained that even one teaspoon of such a syrup would have been more than enough to give a person chronic lead poisoning
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The Romans, of course, were ingesting far more. How dangerous was ancient Roman Sapa
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Well, it was so bad that if it existed today, it would be outlawed in the United States
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And we're talking about a country that loves Big Macs and Four Loko
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In fact, the modern threshold for lead is far, far lower. The Environmental Protection Agency
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will take action when drinking water reaches lead levels of 15 parts per billion
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By comparison, ancient Roman Sapa was practically exploding with lead at a terrifying count of 2,900
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parts per billion. That's nearly 200 times the enforceable amount regulated by the EPA today
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So if lead pots were so dangerous, why did the Romans use them
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Well, for one, they were completely oblivious of the danger. The notion of acid in the wine bonding with lead
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was a little chemistry advanced for them. But more importantly, Roman winemakers
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specifically used lead vessels to make the sapa because the end product would turn out noticeably sweeter
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This, ironically, was an effect of the lead acetate, which, despite being a noxious compound
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actually has a sweet taste. There were also problems with some of the alternatives
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One ancient winemaker wrote that lead pots were better than brass because, in the boiling
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brass vessels throw off copper rust, which has a disagreeable flavor. For Jerome Nregou, researching lead exposure in ancient Rome
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didn't stop at recreating the Sapa. He also researched the diets of over two dozen Roman emperors
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from 30 BCE to 220 CE. Based on his examinations, the scientists found evidence
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that as many as 19 emperors had a predilection to the lead-tainted wine and frequently enjoyed foods
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sweetened with sapa. The inescapable conclusion was that multiple Roman emperors almost certainly suffered from lead poisoning
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That being the case, it's not a far jump to wonder whether the effects of the exposure on the emperor
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might have weakened the empire itself. As noted previously, exposure to lead
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can have many serious side effects For example long contamination can actually impair decision But there were other risks too Roman emperors wealthy aristocrats and others who consumed large
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amounts of lead were also more likely to have conditions like gout. In fact, multiple emperors
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showed signs of having the affliction during their reign. These included Claudius, Nero, Caligula
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and Tiberius. These particular emperors were also known for their odd behavior, which is another
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a thing you would expect of an individual who contracted lead poisoning. Speaking of odd behavior, the Roman emperor Claudius took power after his nephew, Caligula
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died at the hands of Rome's enemies in 37 CE. According to the ancients, Claudius
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who evidently wasn't the hero type, hid behind a curtain while his nephew was getting killed
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After he became emperor, Claudius' rule was marked by numerous uprisings. According to Jerome Nregou, Claudius had disturbed speech
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weak limbs, an ungainly gait, tremor, fits of excessive and inappropriate laughter
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and unseemly anger. Oh, and he often slobbered. I think I met that guy at the office party
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These are classic signs of lead exposure, which dovetails nicely with ancient descriptions
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of Claudius being dull-witted and absent-minded. Or that last part might just mean that ancient historians
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weren't too fond of Claudius. So how often did the Romans use sopa to sweeten their foods
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Well, one 4th century Roman recipe book known as the Apicius, or Apicius, if that's how you prefer your ancient Latin
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included no less than 100 different recipes that all, in one way or another, incorporated lead acetate
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They might have used so much sopa in their cooking because they just love this stuff, but there might have been another more scientific reason as well
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Not too ironically, one side effect of lead acetate exposure is a metallic taste in the mouth
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If the Romans were experiencing that taste, it likely would have encouraged them
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to use even more sapa to cover it up, which would lead to more metallic taste in the mouth
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which would lead to a need for more sapa, which would lead to, well, you get it
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So despite the repeated warnings about lead poisoning, it's likely some of you are wondering
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if there's a way you can make your own sapa. Well, don't worry
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Pliny the Elder has you covered. Pliny detailed the recipe and process for making Sapa way back in the first century
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Sounding like a hipster owner of a microbrewery, Pliny wrote, Sapa is a product of art, not nature
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He then explained that his art began by boiling down the unfermented grape juice
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to a third of its original quantity He was careful to distinguish this from defrutum a different recipe that called for the grape juice to be boiled to one half of its volume Sapa Pliny stressed was more concentrated
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This reduction would have made the sapa much sweeter than grape juice, and the Romans then
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further sweetened it by boiling it in lead pots. While we at Weird History would strongly recommend
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to not use lead pots, the rest of Pliny's recipe still works today. Moreover, sapa itself, to be
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perfectly clear, is completely safe to consume. It's only toxic if it's been heated in a lead vessel
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So what if they hadn't used lead pots to cook the sapa? Would history be different
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Would the Roman Empire have lasted another 1,000 years? It's always hard to answer hypotheticals
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but it's at least possible nothing would be different because even without the sapa, Romans
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still had a lot of lead in their diets. The water many Romans drank was spring water
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that had been transported across the empire in aqueducts and lead pipes
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Those pipes transferred lead right into the water, exposing the population to the heavy metal
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Sapa or no sapa, the Romans were swimming in lead. So about that water, after traveling through the lead
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pipes, Rome's water supply would have become contaminated with lead. How contaminated
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Well, researchers recently estimated that the Roman water supply probably contained 100 times
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the levels of lead that would have been found in local spring water. And this wasn't just guesswork
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it's science. The researchers actually compared sediments from local ports with traces of water
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found in ancient Roman pipes. The scientists ultimately concluded that the levels were
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probably too low to cause significant harm, but they acknowledged that drinking water
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contaminated with any amount of lead can be dangerous and problematic. Given how widely Sapa was used and enjoyed in the ancient Roman Empire
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it's easy to assume that lead contamination was a major problem. But not all scholars agree
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Oh, come on, scholars, just agree on something. In fact, when Jerome Regu first introduced the lead poisoning theory for Rome's decline in the 1980s
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he immediately received a ton of pushback. He argued with other historians who called his theory a myth
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and they claimed the Romans knew that lead was harmful. Moreover, it was pointed out that sapa was used for centuries before Rome's fall
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even during its golden age, which makes it difficult to pin the decline on its use
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And indeed, modern researchers who have examined lead levels in ancient Roman drinking water
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have dismissed the idea that lead could have been the primary cause of Rome's downfall
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Nevertheless, many find it hard to completely reject the notion that centuries of consuming lead-tainted artificial sweeteners
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certainly couldn't have been good for Rome either
#Chemistry