The Best Answer
Technically, as soon as your body relies on fat (dietary or from your own stores) ketones are produced as a result of the different metabolic process which the body uses to create energy from fat. Hence, as soon as your body is burning fat (and not storing it), you are in Ketosis.
"Ketosis" as it's commonly understood in discussions on weight loss and fitness is more of a threshold. If you are relying on fat for a high enough percentage of your energy produced, you are understood as being "in ketosis." This is where the commonly-associated symptoms like bad breath are witnessed. Some of the other symptoms of this state are -- early on -- a sort of brain fog (not something I've experienced on SCD, but I tried a ketogenic diet for fun and definitely had it) as your body eases into energy production largely by fat. Afterwards many report increased concentration and decreased hunger.
You probably can't actually reach this state of "ketosis" by SCD, but as I said: it's more of a definition thing. As long as you're losing weight you can rest assured that ketones are being produced and you are in some form of ketosis. This is why the statements made in 4HB on ketosis are ambiguous.
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