What is "Starvation Mode"

Everyone by now has heard of Starvation Mode but not many people really know what is it?

Hears my understanding in a nut shell.

Our body-fat is stored energy, long-term stored energy, and it is there in case we need it.  The reason why we store it in the first place is a means of survival when food is not present. Think of a bear that hibernates, they eat a bunch of food and live off those stores for several months without eating. When a bear hibernated their metabolism is extremely slow they can live longer on what they have.

Metabolism is really 2 parts, 

• Part one is our normal every day body functions, from our brain, to the growth of our toe nails.  
• Part two is the digestion of food, when we eat our body metabolizes the calories and sends them where they need to go.

The first part of metabolism is pretty steady 24 hours a day, when we sleep we are not active physically but our brain is extremely active and our brain alone needs about 100 grams of glucose daily. 

 

Part two is a variable, if we eat 5,000 calories we have a lot of food to metabolize, if we eat 1,000 calories we have far less. Also the type of calories matter too, if we have 1,000 calories of protein, we will need about 300 calories to metabolize the protein into amino acids. If we have 1,000 calories of carbohydrates, we only need about 70 calories to metabolize it.

 

So by simply dieting and eating less calories, we burn less daily through metabolism.

 

But the true meaning of Starvation Mode, is when our overall metabolism slows down because through our dieting our brain believes food is scarce and it slows down our overall calorie burning to prolong the use of our fat stores to help us survive longer, much like the bear hibernating.

 

It can take a few weeks for true starvation mode to kick in, I believe it is gradual and happens quicker with more extreme diets.

BUT, from the first day of your diet, when you begin eating less you will begin burning less through metabolism because of the second part.

 

There was a study done on the 1940's that proved that there is pretty severe slowdown of metabolism with restricted calories called the Minnesota Semi-Starvation Study. 

 http://en.wikipedia.org/wiki/Minnesota_Starvation_Experiment