In this video https://youtu.be/T7o_hF1XB84 doctor Jason Fung mentions that ketosis begins after 2 days but many place I read it starts after 12-14 hours.
What’s the correct answer?
It depends on how adapted your body is. If you regularly follow a keto diet it is easier for your body to achieve ketosis than for someone whi does th at their first time. When I first started it took me about 24h to get into ketosis now, 2 years later I’d say it takes somewhat between 12-18h (shorter if i get a cardio session in 😊) Only way to know for sure is urin or blood testing. Good luck with your journey, hope this helped!
Most ppl on a western processed diet are not gonna reach ketosis in 12 hours. Way too much stored glycogen. I took two weeks off of keto for my bachelorette party & took a little while to get motivated again. Went from decent eating but not keto for 2 days to a full fast but with coffee/little heavy cream with teas & electrolytes. I test with keto strips every day. It took me 40 hours to get back to ketosis with fasting & it was saying “ketosis plus” on my zero fasting app at like 30 hours when I was still not showing any signs of ketosis so I would definitely be more inclined to believe dr fung & get keto strips or a meter…now if I’m on keto more consistently & fat adapted & have a cheat meal I’m back in ketosis within 12 hours but that’s only if it’s a cheat meal or two if it’s more carbs than probs like 100 grams of carbs probs full 24 hours even being more fat adapted…(just estimates)….also exercise can play a role in getting you into ketosis faster. I was walking 17,000 steps and doing light yoga each day of my first two days with still no signs of ketosis. If I were doing 3 hour uphill bike rides I probs could deplete my glycogen stores faster. These are all just my opinions based on my own keto sticks measurements for the past several months with keto & fasting & reading a lot about these things like Dr Fung’s work.