Hi Claire,
Ketosis is when fat is being burned off rapidly by the body and it produces substances from the fat called 'ketones' and the person is said to be in 'ketosis'.
This mild 'ketosis' produced by a vlcd is called diatary ketosis and it has a nubmer of advantages for dieters in that it reduces hunger and a feeling of well-being is often experienced.
Ketones can be detected in the urine and this can provide encouragement that the body fat is being burned.
Ketones can sometimes be detected on the breath and this is only temporary and can be reduced by adequate water intake and mouth rinsing with a mouthwas like Oraldene or Listerine. I find myself a tongue scraper is a big help at the start as I seem to get a furry tongue...but this goes away and of course I still keep my flossing up as it is improtant.
Because the low sugar level is critical to maintaing ketosis, it is very important not to eat or drink anything else, apart from your daily servings of CD/LL/LT which ever programme you are following. You are allowed black tea and coffee and if you need a sweetener, it is recommended that you use tablets as the spoonable powders contain some sugar in order to make them spoonable.
It is ver important to drink plenty of fluid for your comfort.
If you cut down on carb a few days or a week before starting your vlcd it will make all the difference as you will not go through the withdrawal from carbs in the same way as if you go from a last supper into the diet.
Also you will go into ketosis much sooner.
Headaches in the first few days occur due to lack of fluid and carb withdrawal.
Love Mini xxx