When dieting, it’s often said that one should never dip below 1,000-1,200 Calories a day in order to prevent one’s metabolism from entering “starvation mode.” My understanding is that crossing into that mode means your body begins storing more fat, meaning that the diet begins to have an adverse effect on the body.
Consider the following scenario. There are two people, one weighing 285 pounds at 33% body fat, and the other at 125 pounds at 10% body fat. Both of them go on a crash diet (who knows why the skinny guy is on a diet, but it’s a darn good thing for our hypothetical here that he is) that takes their Caloric intake down to about 750 Calories a day.
Here’s the question, then: will they both enter this “starvation mode” of metabolism? Will there be a difference in the amount of time it takes each of them to enter it? I’m not a physiologist or nutritionist or anything, but it just strikes me as odd to think that a 285 pound man’s body’s first reaction to such a deficit would be to pack on more fat.
I think that if you cut your daily caloric intake by about 20% not to go below 1500 calories, you will not starve and you will lose weight (with exercise) of course.
The problem lies with your understanding of what happens.
The human body has evolved to deal with seasonal deficits, in large part because seasonal drought is normal in savanna environments. One of the ways it does that is to respond to a food deficit by doenshifting the metabolic rate. This isn’t something magical, the body simply moves slower. Pople become sluggish, they sleep longer, they fidget less, they are less inclined to exercise and they become listless and the body temperature drops and becomes more stable on a daily cycle.
That is why the rate of weight loss can decline under starvation. Note that weight loss still occurs, but it may occur somewhat more slowly. Someone living anythingliek anormal life and eating 1000 or fewer calories a day will not pack on more more fat, they will continue to lose weight. You can’t possibly gain weight if you are eating fewer calories than your body is consuming.
So the reason not to starve yourself is twofold: firtsly it’s less efficient because the rate of weight loss declines and your propensity for exercise declines which exacerbates the effect. Secondly nobody sticks to their diet. People always break their diet, and if the body is in starvation mode it will make most efficient use of the extra calories you take in in this manner. A normal person who is breaking their diet on every few days may well put on weight, but it’s not because they are consuming less than 1000 calories a day, it is because they are alternating between starvation days and high food intake days.
And all things being equal the effect is just the same regardles of the amount of body fat you’re carrying. No matter what size you are if you are actually consuming less than 1000 calories a day and living a normal life style then you will lose weight.
Blake, that was an excellent explanation, thanks! I mentioned in another thread somewhere that my main hobby is weightlifting, but the nutrition side of…eh, let’s call it “body sculpting,” has always wooshed me.