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On a recent trip to Japan, I found a fiber-forward soda that tastes like Diet Coke and keeps things moving
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Lauren Gould Sun 27 Sep 2026 21.20 CEST Share Prefer the Guardian on Google On my recent vacation to Japan , I learned they are light-years ahead of the US in many ways – from their high-tech toilets and efficient bullet trains to … diet sodas.
Amidst the chilled bottles of Coke Zero and Sugar-Free Pepsi stocked in the fridge of practically every 7-Eleven was another mysterious beverage in a bright white can – Coke Plus , which my friend heard about from the internet’s goldmine of travel videos.
Unlike Coca-Cola’s other diet sodas, Coke Plus has 5g of indigestible dextrin fiber, which it says can “suppress the absorption of fat from food and moderate neutral fat level spikes in the blood after eating”. Its target market? Adults 40 and up .
Coca-Cola Coke Plus from $6 $6 at Japanese Taste $50.50 at Sugoi Mart (pack of 16, $50 minimum purchase required) Coke Plus was ahead of its time. It debuted in Japan in 2017, before the fibermaxxing craze came to the US. Its launch attracted national attention, earning coverage in outlets such as New York Magazine and Business Insider . Despite the buzz, it never enjoyed a wide US release. Japan’s demographic skews older – over a quarter of its residents are at least 65 years old – which may, in part, explain its popularity.
Even though I am likely not the target audience, my friend and I each downed a bottle to sneak in fiber amidst the plethora of sushi, onigiri and matcha we were consuming. “Missing those fiber cokes. I don’t think I’m the same w out them,” my traveling companion texted me about two months after we had left Japan.
There are plenty of other fiber sodas that haunt the beverage aisles of trendy grocers and chain supermarkets alike. Most come in the form of pre or probiotic sodas, claiming to “support gut health”. Olipop, for instance, launched in the US just one year after Coke Plus and is now valued at almost $2bn . In the last decade, new brands have emerged with similar options – including Poppi and Culture Pop. In 2025, Coca-Cola released a fiber soda that you can buy in the US – the prebiotic Simply Pop , though its fruit juice concentrate and monk fruit sweeteners are a far cry from Coke Plus’ flavor.
Coke Plus is decidedly not a prebiotic soda. In my opinion, it tastes nearly identical to a regular Diet Coke – a familiar and comforting beverage experience for when I’m not in the mood for the flavors of apple cider vinegar or stevia, which are prevalent in the Coca-Cola flavors of other prebiotic sodas.
While Coke Plus has roughly half the fiber of Olipop, I found that it helped keep things moving during my travels . But even if the added fiber was a placebo effect, sipping on one midday made me feel less guilty – it tasted just like the chemical-filled beverage that my generation refers to as “ fridge cigarettes ”.
As it turns out, I’m not the only one longing for the comforting, familiar taste of a Coke Plus. It’s the subject of Reddit threads, with one user calling it “magical Diet Coke ”, and it’s one of the Japanese e-retailer Sugoi Mart’s best-selling beve…