Does fasting really cause metabolic slow down?

A few years ago I was at a health and fitness expo, it was in the very early days of me starting Schkinny Maninny and I had a stand to exhibit, give taste samples and help people learn about the benefits.  I will never forget that weekend as I was harassed and harassed by personal trainers telling me that doing a juice cleanse would do nothing but slow your metabolism down.  It was horrible.  And they were at least partially right.  So I spent most of the weekend trying to say ,”but…”

Prolonged periods of fasting does put our bodies into “starvation mode”, our bodies start to prioritise the feeding of internal organs and  hold onto whatever calories may be consumed to keep us alive rather than keeping us looking svelte.  But I guess there was a bit of mystique around what “prolonged” meant.   

 Fast forward a few years and now we know that prolonged is exactly what it means, like 2 years.  So a period of 3-7 days is not “prolonged” and can’t really be deemed to impact the body in the same way.  Now we have seen clinical studies that show when you fast your body actually burns FAT stores first to help fuel your body, so concerns about losing significant amounts of muscle whilst short term fasting are simply untrue.  When you expose yourself to long term full time calorie restriction, then starvation mode is a real phenomenon and your body will start to do things like burning muscle for fuel.  But on the short term it is a great way to help burn up those fat stores, but just make sure when you start eating again, eat lots of fresh whole nutritious foods rather than smashing burgers.


Catherine Craig
Catherine Craig

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