SUGAR, FRUCTOSE AND BLOOD SUGAR...
If we turn back the clock to when we lived, let's say, "in and from nature": When were carbohydrates available back then, and in what form? A few berry bushes in the forest? And when were these available as a food source? Perhaps for two or three months of the year? And yes, that's right: That was before winter, a time when food was scarce. So, was it sensible back then to build up a small energy reserve in the form of visceral fat ("spare tire")? Absolutely. Does it make sense today to trigger this "fat storage mechanism" 365 days a year? I'll leave the answer to that for you...
I believe that carbohydrates don't have a good energy balance. This statement sounds provocative given that in moments of "weakness," we crave something sweet, something starchy: a chocolate (or muesli) bar as a snack, cake, gummy bears, but also pasta for lunch or bread for dinner. These "sugar bombs" give us a short-term boost. Or maybe not, because if we're honest with ourselves, after a lunch of pasta, potatoes, and the like, wouldn't we just want to lie down and sleep?
But be careful: Carbohydrates, sugars, etc., don't they contain a lot of energy (calories!)?! Marathon runners need them; they fill their glycogen stores before the race! The brain only functions with glucose, i.e., sugar! Or is it not that simple?
Sugar is bad, that much is clear.
Fructose from fruit is surely the healthy alternative?!
Or: Why an apple (from a biochemical point of view) is twice as toxic as alcohol [1] .
Fructose, which most nutrition guides describe as a "healthy sugar" and almost always recommend, occupies a special position in carbohydrate metabolism. Since the body cannot directly burn fructose, it must—to put it simply—first be converted into glucose. This happens in the liver, and its capacity for this process is quite limited. Excess fructose is converted into fat deposits, which accumulate in the liver. This leads to fatty liver disease. Speaking of fatty liver disease: it's a common condition in alcoholics. In this context, I'd like to point out that the LD50 [2] —a standardized toxicity index that indicates how much of a substance one would have to ingest to die from it—exists for almost everything, including water. For water, this value is 90g per kg of body weight. So, I would have to consume around 7 liters of water to die from it. The value for refined table sugar is 30g/kg and for ethanol (alcohol) it is 7g/kg body weight. And now for the kicker:
The LD50 toxicity index of fructose is 4g/kg.
In my case, that means around 300g of pure fructose would be fatal.
These figures alone, in my opinion, illustrate what a dangerous game fructose consumption is in the form of fruit, fresh fruit juices, corn syrup, etc.! Furthermore, regular fructose consumption is also linked to fatty liver disease, cancer, metabolic syndrome, diabetes, cognitive decline, and more. [3] [4]
[1] https://www.aatbio.com/resources/toxicity-lethality-median-dose-td50-ld50/fructose vs. https://www.aatbio.com/resources/toxicity-lethality-median-dose-td50-ld50/ethanol
[2] https://flexikon.doccheck.com/de/Therapeutische_Breite
[3] https://pubmed.ncbi.nlm.nih.gov/24257416/
