In reply to Josie Garner.

It takes approximately 3 days to achieve ketosis if eating under 30g carbs per day because our body can't store too many carbs (glycogen) and uses up all reserves in the liver and muscles in that time frame. It's even faster if you work out because your body burns the glycogen. You can do a quick Google search and find plenty of supporting information about the 3 day period to hit ketosis when eating low carb. From there, it's a matter of maintaining it by continuing to eat low carb and reaping the full benefits over the coming weeks and months.