The concept of the "starvation mode" is based on both fact and fake marketing BS. Or better yet, more accurately a misunderstanding of the facts. The idea behind the concept states: if you consume too few calories your body slows your metabolism so much causing your body to go into a state where fat loss is no longer possible.
So let's think this through. To lose fat you need to be in a calorie deficit. However, if you lower your calories too much you'll put yourself in "starvation mode". Hmm, something doesn't sound quite right here. That's because somewhere along the line, someone took some really good research and turned it around for whatever evil reason those folks have to do such a thing.
Now the facts, starvation mode is based primarily on adaptive thermogenesis. Which does show that having a caloric deficit does actually slow down the metabolic rate...over time. However, the rate at which the metabolism slows is not substantial enough to actually stall your weight (fat) loss. Likewise, it won’t make you gain weight either.
Buuuttttt, you may still be seeing a lack of progress or even weight gain. Why is that you ask, well because once you have lost mass you no longer require the same amount of calories you did when you were a bit larger. Did you decrease your caloric intake after the weight loss? You could be once again eating too much. You are also moving less mass around which equals less work. Less work= fewer calories burned. So going back to the basics if your caloric intake is more than your body is able to burn, guess what? You got it, you’re going to see your progress stalled or even go backward. It doesn’t get much simpler than that! To read more in-depth on this topic visit www.aworkoutroutine.com/starvation-mode/ or www.physiqonomics.com/eating-too-much/. These guys really break it down...in a very interesting way!