Intolerance to high amounts of fructose?

Nutrition
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Tldr: It seems that I cannot tolerate certain amounts of fructose (mild symptoms). Have any of you experienced this as well?

When I started upping my carb intake during cycling last summer, I observed that I often felt bad afterwards. It was particularly strong after long rides during which I consumed 200g+ of sugar. Symptoms were: feeling hot (especially in the face), a little dizzy, runny nose, very mild feeling of being sick, not hungry at all and slight skin rash the next days (I get these easily, usually an indicator that I eat badly or that I am sick). I attributed these symptoms to the long rides in the heat and problems with hydration. However they persisted into the colder months. I think (not 100% sure) that I sometimes get such symptoms after eating lots of sweets, but I never thought much of it.

I forgot why but in the last months I started drinking maltodextrine instead of a sugar mix on the bike (up to 60-70g/h). And funny enough I had none of the symptoms described above, I felt totally normal.
The only obvious difference I can find is much lower fructose intake. Googling „fructose intolerance“ brings up rather harsh symptoms and it seems I can tolerate some amount of fructose, so I am probably not intolerant. However lots of sources/websites talk about how bad fructose is for the system and 200-300g of sugar is quite an amount.

Since I can‘t find much about „mild fructose intolerance“ or similar, maybe it‘s something else? Have any of you had similar experiences?

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Not really having the same issue but i tried just training with plain suger and it didn’t feel great. Guess that’s because table suger is 50/50 in glucose/fructose. So 120grams of plain suger might be to big of a percentage of fructose.

When i mix my own bottles with 2/3rds maltodextrine and 1/3rd fructose i’m fine.

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120g per hour of any combination is too much for most. That is at the upper limit and I’d expect most to have issues. 90-100g seems achievable for the majority of individuals who work up to that amount over time. Anecdotally I regularly handle 100g of sugar for many hours without issue, however if I go closer to 120 I’m having gut distress after a couple hours.

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People without fructose intolerance have a limit for the amount of fructose they can absorb without problems, it’s just much higher than the limit for those with fructose intolerance. So what you have is probably a pretty normal result of too much fructose.

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Possible that you just need to train it or in fact have an issue with it.

Isolate the variables. Consider trying straight fructose in your bottles. Start small and work up. 20/30/60g/hr

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