Do you mean added sugars or fake sugars, or are you really trying to make due with polysaccharides and a little bit of glucose? Didn’t think ketosis is a good long term source of energy…. The engine is build to run on sugar (Krebs cycle).
You’re correct that Krebs cycle is involved but it’s a cycle so the inputs do not have to be solely carbohydrates.
Here are more details https://ketoschool.com/summarizing-the-science-behind-ketoge...
I’m almost 6 years deep to this diet and my yearly lipid/glucose/blood work up has been all good. Both my actual doctor and my family members have been very concerned about my BUN and creatinine levels.