Anyone know why cancer cells are harmed by ketogenic fasts? I can see why cancer cells fail to thrive during periods of fasting, as their reproduction halting mechanism is broken and they will burn through all their energy when none is available. Why is it that health cells can function off ketones but cancer cells cannot however? Where is the evidence that it works as well?
My understanding is that the idea that cancer uses glucose for energy is from Otto Warburg (who got a Nobel Prize on it). Basically he found that cancer cells don't metabolize the way normal cells do. They breakdown glucose in the cell cytoplasm and their mitochondria are disfunctional. Regular cells use the mitochondia and cytoplasm to metabolize glucose. Ketones are metabolized in the mitochondria only.
So, based on this, if you throttle the food source by lowering the glucose and go ketogenic, you provide energy to your cells that can't be used by the cancer cells. Since there's little to no glucose for the cancer cells to thrive off of, they stay the same or shrink. You never go to 0 blood glucose due to gluconeogenesis. But you can definitely restrict the amount available.
There have been studies showing this works. However, there is not one type of cancer. There's actually tons, all doing different things. So the potential exists for some variants that could live off ketones. Apparently there's a study indicating this, but there's some serious outstanding questions on their methodology.
From what I recall cancer cells thrive when there is a readily available source of sugar. A ketogenic diet drastically reduces blood sugar levels, thereby "starving" the cancer cells.
Here are a few links from a quick Google search on 'cancer glucose':
Hope this helps...
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