Everybody seems to be talking about fasting these days and the impression that I get from articles I am reading is that it is good for everyone. But that is not strictly true.  I am talking here about intermittent fasting not fasting for days or weeks.

Muscle loss will occur if fasting for extended periods as your body starts to cannibalize your own muscles to stabilize your blood sugar and this is not advisable.

So lets talk about intermittent fasting, what it is and what it does to your physiology.

To understand fasting physiology we need to talk a little about blood sugar if you have read my previous articles about blood glucose you will know that when you eat your blood glucose will go up. After about 4-5 hours you will need to eat again to maintain your blood glucose levels, hence the usual gap between meals of 4-5 hours during the day. 

Fasting is normal, especially at night - if you are eating your evening meal at 6pm and your breakfast 8am you will have had approximately 13 hours of fasting.  So in order for your body to maintain a good level of blood glucose, it will have to produce glucose in your liver by burning fats and proteins.  Your body will do this automatically while you are asleep.

The capacity for your liver to burn fats is why fasting is often used as a weight loss strategy.  It utilizes the natural fat burning capacity of your body.  Correctly implemented you can make your body burn fats and proteins to stabilize blood glucose, you will loose weight and help stabilize your blood glucose and insulin levels at the same time.

If your blood glucose levels are high and you are trying to loose weight then intermittent fasting may be part of the solution for you.  But it is also important to change the types of food you are eating before you start fasting. If you continue to eat a high carb/high sugar diet you may find fasting very difficult. This is because your body is not used to converting fats and proteins into glucose, and is finding it hard to stabilize your blood sugar. Making dietary changes before you starting fasting will be very beneficial.

If on the other hand you find that you wake in the night, don’t function well unless you eat or get cranky when you skip meals fasting may not be the best solution for you.  In fact you may have lower than optimal blood sugar and fasting should be avoided.    In fact for people in this group fasting will make you feel worse and you may need to do the opposite and eat more regularly.  You should focus on eating more protein and healthy fats to keep your blood sugar stable throughout the day and the night.

The general advise which is good for everybody is to eat 3 meals a day and have a large gap (fast) between dinner and breakfast. If you are trying to manage blood sugar problems or weight issues then fasting may be appropriate. However for those with a functionally low blood sugar level then fasting is often problematic.