This old lie again? This study just shows that four attempted diets, none of them particularly sophisticated, all work equally well - which is to say, not very.
Yes, the laws of thermodynamics hold, but what if, oh, say, what you ate had an influence on how much you felt impelled to eat? Or how energetic you felt and how much you moved around? If your fat cells are rapidly absorbing what's in your bloodstream, you'll feel hungry and eat more, and you'll feel tired and move less.
The number one experimental result of dieting is that 95% of the people gain back the weight a few years later.
If Seth Roberts is right, all we're seeing from this study is a temporary bump that results from changing your food habits in any direction, which leaves behind the old flavor-calorie association, which makes you less hungry. And if they stick to this diet a while, they'll develop new flavor-calorie associations and gain back the weight. (This is a very elegant theory which, among other experimental support, explains a lot of the chaos in dietary science; almost any dietary change makes you lose weight, but only temporarily.)
Sorry, metabolisms are just more complicated than this. Call me back when they test Loren Cordain's or Seth Roberts's theories.
Applying the 80/20 rule, metabolisms most certainly are not more complex than than a simple input/output equation for a vast majority of people.
We have been around in this planet for thousands of years, a vast majority of which spent by a vast majority of people in a non-obese way. Evolution has tuned our bodies not to be overweight so long as we don't change the equation of calories in to calories expended.
Our modern North American lifestyles have adjusted both sides of the equation, hence, obesity is an epidemic. Adjusting the equation back is a huge step forward, regardless of outliers.
Look at the military. Diets aside, the simple reason there are no large obesity issues within the organization is that they purposefully modify the output side of the equation. Diets don't work because the modification to the input side is always only a temporary change.
We eat too much and move too little. Duh. While the dynamics become more complex at the elite athlete level, and there is a segment of the population that could be considered outliers, if we all simply made the equation balance, we'd see a huge drop in obesity rates.
It still complicated, though. For example, eat 1500 calories a day while your metabolism uses 1800 or so. Sounds foolproof? What if those 1500 calories are all sugar? There goes your metabolic rate and your body fat will go through the roof. What if you eat 60% protein, 30% fiber, 10% fat? You will probably wind up looking like a career athelete, even if you never exercise. The composition of the calories has a huge effect on their usage (through the mechanism of you hormone feedback systems). It may not be rocket science, but the body is complex to the point of being a black box for most people.
I don't think anyone denies there is a huge part of dieting that is changing habits, lifelong habits. But most of them are just methods of consuming fewer calories.
Most people would have an easier time losing weight if they just stopped eating before being full. Being full should be a luxury, not a daily occurrence. All the studies about "obesity genes" are more focused around the appetite, not anything about metabolism. Appetite is a feeling, sometimes in life your feelings are not always the best method to drive your actions.
As someone who lost 70 LBS 3 years ago without a 'diet' and kept it off, this article strikes me as overly obvious. Anyone who has ever actually seriously lost weight and kept it off knows that everything comes to the bottom line: calories consumed vs. calories expended.
Formula for HN: ((calories consumed - calories expended) / 3500) = weight change in LBS of fat. There are healthy ways to lose and gain weight and there are unhealthy ways, but they all come down to that very, very simple formula.
It's not that simple. For one, you want to lose fat weight, not muscle, bone, etc. weight. How does your body consume or store fat? It depends on available calories, the caloric composition, and your hormone feedback systems. Arguably, the hormones exert more control than anything else.
It gets more complicated from there: hormone's respond to what you eat. Eat more sugar, it raises your insulin (a hormone) which will stop the conversion of fat to energy, and indirectly will cause the conversion of blood sugar to fat. If your insulin is improperly regulated, you'll have difficult following the simple formula above. The same goes for thyroid hormones. They regulate your metabolism. Another hormone involved is cortisol which reponds to stress levels and can increase your blood sugar levels (cascading over into insulin, for example). Note that you can run into the non-intuitive case of over exercise increasing your cortisol causing excessive blood sugar causing fat storage. It's not easy, but it is possible.
One way to look at it simply is to eat foods that control your blood sugar, and manage your stress levels to avoid excessive cortisol. Excessive protein and fiber calories won't cause fat to build, going against the above formula. In fact, protein and fiber are excellent blood sugar regulating foods and are therefore good at controlling fat building.
Simple, yes, but too simple. That formula ignores the fact that (all things being equal) as your weight drops, your basal metabolic rate drops as well. This means that with each pound you lose, it becomes harder to lose the next.
This is why exercise is critical for losing weight. Exercise counteracts this effect by raising the metabolic rate.
That's the thing: It doesn't ignore anything. If your basal metabolic rate drops, that means you are expending less calories through those means. The bottom line remains the same. You'll either need to consume less calories as a reaction, or up your calorie expenditure through increased exercise or through metabolism 'tricks' such as consuming increased (but safe) levels of water.
Let me illustrate what I meant with an example. Based on your formula, if I wanted to lose 10 pounds over 10 weeks, needing a deficit of 514 kcal/day, and my basal metabolism rate were 1800 kcal/day (roughly what mine is), ignoring exercise I would need to maintain a diet of no more than 1284 kcal/day.
How I interpreted your first comment was that you were arguing this would work for the entire 10 week period. My point was that it would not, that over time the rate of weight loss would slow as your basal metabolism rate drops. Given a constant diet, at some point an equilibrium will be reached.
Do people really need to be told this? Calories == Energy. If you kept putting more gas in your car then it uses its gonna spill out all over. If it could store the overflow, like the body does, your just gonna have more lying around.
Despite what the diet book cartel wants people to believe, energy production and usage by the human body is not all that mysterious.
If you tell people that the secret to losing weight is "eat less and exercise more", they a) think its too simple to work and b) too onerous to actually do.
Delta in mass = inputs to the system - outputs from the system - energy expended by the system. If you desire negative deltas, decrease inputs, increase outputs, or increase energy expended. (Options #1 and #3 are probably better for most people, owing to the inability to control #2 in a safely scalable manner.)
The human body does not get a free pass from physics just because its details are complex.
I'm right there with you. All you need to know about losing weight is this:
Don't eat so much.
Problem is people won't believe you and it is unmarketable. So, companies go out and produce candy bars, market them as diet food by slapping a label on them that says, "eat this and not much other stuff and you'll lose weight."
I never said it was easy. It took me two years to figure out _how_ to eat less when my metabolism magically changed. There is nothing in any book could have helped me with that. Each day was an experiment. Still is, but the bottom line is I don't eat as much as I did before and the things I do eat just happen to be classified as "healthy." It's a big PITA.
Yes, calories==energy. But why is it necessarily "spill out all over"? If thermodynamics apply (and they do), then adding more fuel to a fire makes the fire burn hotter. Or, to keep the car analogy, pumping more gas to the engine makes the engine run faster, and thereby consume all the fuel being pumped into it.
So, by analogy (and since we're talking about simple thermodynamics), eating more calories should make your metabolism run faster. More fuel, more fire, higher rate of fuel consumption. This is definitely true for those people who can eat lots of food and never get fat. Ectomorphs.
So, why doesn't this rule apply to everyone? Why do some people store what they eat as fat and others just burn it all off regardless of how little they exercise. Why aren't we all ectomophs? Genetics may come into play, sure, but all humans have the same genome.
The difference must be related to differences in our bodies. Which means differences in hormonal reflexes, differences in responses to certain types of food, etc.
It is about calories, but it's not _just_ about calories. It's about our bodies, too, and how we've conditioned them to process different kinds of foods.
Highly recommend "Good Calories, Bad Calories" by Gary Taubes.
Adding more gas to a car will not burn more. There is a system to regulate the consumption of fuel (throttle) just as a human body. Its not a burn pit.
And is this old metabolism debate still going on? Last time I checked most overweight people actually had higher metabolic rates.
While I agree with the overall premise (it's very "duh"), there are some things worthy of more exploration:
The people in this study really didn't lose all that much weight. Do certain diets promote faster weight loss?
Also, I find it ridiculously hard to believe that a study that uses obese people, who have trouble controlling their weight in the first place, can maintain a strict caloric deficit for two years.
Additionally: It doesn't really say much about body fat % - does eating certain ratios promote muscle growth, yet fat loss? (this is a premise in the high protein diets)
"does eating certain ratios promote muscle growth, yet fat loss? (this is a premise in the high protein diets)"
I think the key thing in extreme dieting is to ensure no loss of muscle. An obese person is going to have to take drastic measures to lose weight, and are highly susceptible to malnutrition (many times they're already malnourished due to poor diet to begin with) and cutting the amount of food you eat in half can be dangerous.
The key problem with anorexia isn't that they have such low body fat (it's a problem, but it's unlikely to kill you) it's that they don't intake enough protein. Once there's a shortage, your body starts using muscle inside your body, and unfortunately there's a extremely highly protein dense half-pound of muscle we all know as a heart.
What the Atkin's diet is great for is that if you drastically need to lose weight you can do it without causing serious and irreparable muscle damage and potentially heart damage.
If you're wanting a long-term (as in 1 month or longer) change in diet then protein is key for exactly what you said. Most obese people are at high risk of things like hernias as most never built up the muscle in the abdominal wall and are literally a ticking time bomb.
While I'd have to agree the results seem "only logical" or "obvious," the media hype and the public hope for an easy silver bullet mean that these types of results really deserved to be trumpeted aloud to the general public.
To me the bottom line for science is "The real question for researchers, Dr. Sacks said, is what are the biological, psychological or social factors that influence whether a person can stick to any diet."
The next steps seem to involved behavioral sciences, not biological sciences.
Yes, the laws of thermodynamics hold, but what if, oh, say, what you ate had an influence on how much you felt impelled to eat? Or how energetic you felt and how much you moved around? If your fat cells are rapidly absorbing what's in your bloodstream, you'll feel hungry and eat more, and you'll feel tired and move less.
The number one experimental result of dieting is that 95% of the people gain back the weight a few years later.
If Seth Roberts is right, all we're seeing from this study is a temporary bump that results from changing your food habits in any direction, which leaves behind the old flavor-calorie association, which makes you less hungry. And if they stick to this diet a while, they'll develop new flavor-calorie associations and gain back the weight. (This is a very elegant theory which, among other experimental support, explains a lot of the chaos in dietary science; almost any dietary change makes you lose weight, but only temporarily.)
Sorry, metabolisms are just more complicated than this. Call me back when they test Loren Cordain's or Seth Roberts's theories.