When we lose weight, we're losing energy, and that energy can be accounted for.
In other words, you’re not losing weight because you’re eating less; you’re eating less because you’re losing weight. It’s also theoretically possible to eat the same number of calories and lose more weight on a low-carb diet, despite what you hear about “a-calorie-is-a-calorie.” You wouldn’t be violating the laws of thermodynamics, somewhere along the way you’re creating the deficit, whether it can be measured by an indirect calorimeter or not might be up for debate, but if you’re eating a diet that liberates more fat - or interchangeably, more energy - you will be more prone to utilize it (burn it). These are also most likely to be the people that we "hate" who can seemingly eat whatever they want and not gain an ounce.
Now that you have put your body in position where expenditure is exceeding intake at the level of the fat tissue (rather than thinking about it from a whole-body perspective, i.e., calories-in/calories-out which I think is a grave mistake), you should be relatively satiated eating almost 1000 calories less than what you may have been used to. This is what happens in Atkins subjects in clinical trials. They are told they can eat as much as they want, but will wind up eating less than they usually do and I think it’s because the fat is liberated from the fat tissue whereas in a high-carbohydrate (especially the most refined and easily digestible) diet, insulin levels remain relatively elevated in many people and it not only stores more calories as fat, it also inhibits the mobilization of fat.
The Atkins subjects are supplementing their diets with endogenous calories which decreases the exogenous requirement from food. Taubes pointed this out to me years ago using a quote from a physiologist (Jacques Le Magnen) who said, “It is not a paradox to say that animals and humans that become obese gain weight because they are no longer able to lose weight.” (I think he referenced this in WWGF as well.)
Generally, when you do chronic, lower-intensity cardio, you may not be benefiting from any internal changes in the body. Also noted in WWGF, and in a New York Magazine article by Taubes, when you exercise you down-regulate LPL, which is an enzyme that increases fat accumulation and you up-regulate HSL, which increases fat mobilization.
Hey, good times! We're in fat-burning mode as our trainers so often tell us, and this is the key to fat loss, so if we can keep our- [cue the record scratch]
With interval training there appears to be more compelling evidence that you can change the “milieu interior” and perhaps become a little more insulin sensitive in the right places, secrete a little more growth hormone, testosterone, IGF-1, etc. and therefore change the partitioning of fuel in your body, which can help with body composition. However, it's not beyond the realm of possibility that in the future I will be inserting another record scratch and finding that compensatory mechanisms might be at play here as well.
Again, people that I "hate," are the ones that "eat too much" and their biceps get bigger and their waist size remains the same.
Over time, as you have less excess fat to lose, I do think the weight loss becomes slower. A fat cell is not immune to the laws of pressure gradients so that a fat cell that is more filled with fat presumably will release more fat so long as it is provided the necessary hormonal and enzymatic environment (which is promoted by restricted-carbohydrate diets, and diets that don't include much in the way of refined carbohydrates and sugars).
I often receive Biggest Loser questions related to these ideas above, which generally are:
1. How can a woman possibly lose 14 pounds in a week? I am mystified by this!! How can you burn 7000 calories a day?
2. I heard ( or saw on the menu board), contestants were eating 1200 calories for the whole day. [And Dr. Dansinger, the Biggest Loser nutritionist claims they're eating somewhere in this range, around 1500 calories, and also claims weight loss is all about caloric reduction) around 1500 calories] Does anyone know whether this is accurate? I thought it was dangerous to eat this few calories, especially with tons of exercise?
If you're 200 pounds overweight, you have 700,000 calories of energy in your fat tissue. If you can get at 1% daily, that's 7000 calories, so you could see quite significant fat loss in the early stages of a program where fat loss is stimulated.
I'm somewhere in the neighborhood of 185-190 lbs and 10-13% body fat, so I have, say, 20 lbs of fat. Liberating 1% of this would give me closer to 700 calories, so fat loss will be slower.
And looking at this, any small fluctuations in the rate of fat mobilization is going to be profound. I kind of look at primal eating as a way of liberating the excess fat.
Then I thought about depreciating 200 pounds of fat, or 700,000 calories at a rate of 1% per day over 1 year and how it would look on a chart, and it really flattens out (see chart below). Granted, this would take someone from 200 fat lbs to about 6 pounds of fat over a year, but the last 6 months are mostly losses of less than 1 pound of fat per week. And this is given a perpetually favorable/perfect internal environment of the body.
2. This is a very crude measurement, but if they're eating 1200 calories and exercising presumably 8 hours a day, where do you think they get the energy to fuel the workouts? See question 1: if they're liberating 7000 calories worth of fat from the fat tissue; they're "eating" 8137 calories, 86% is derived endogenously (from fat), while 14% exogenously (from food).