I think he's suggesting that obesity is a function, at least for the vast majority of people, of the total number of calories consumed vs. the total number of calories burned. If so, he's correct. If you burn more energy than you consume, you will lose weight. If you exercise regularly, you will burn even more calories than by only employing calorie restriction. Pretty simple, really. Although the people out there touting the latest diet fad, while selling their latest diet book, will vehemently disagree, the macronutrient ratio is not all that important. What really matters is total energy consumed vs. total energy burned.
Also, a calorie is a measure of the amount of energy. This is how a calorie is defined. As such, a calorie will always be the same. When your body metabolizes fat, amino acids or carbohydrates, different pathways are used for each and the efficiencies will not be the same for each process. Even so, a calorie is always a calorie.
Taubes has made a good living demonizing one macronutrient over another. That may be an effective way to sell books, and earn lecture fees, but it doesn't offer much for those looking for something other than assumptions being presented as facts. Taubes touts the Atkins diet, but Atkins is really nothing more than a low calorie diet in disguise. Taubes also seems intent on denying the basic thermodynamic perspective. Taubes isn't a scientist. If he were, he'd know that calories are the bottom line.
I’m assuming that some people burn a larger percent of the calories they consume.
I wonder if a study has been done that carefully measured calories in and calories pooped out to try to figure out what is happening. By comparing this to their diets, we may see some patterns.
If it is true that some people can eat all day and not gain weight and others gain weight if they eat the same and gain a lot, then we should be able to find the calories somewhere.
If the thin people are burning it off with an elevated metabolism, we should see a higher average body temperature and more CO2 in their breath.
No matter what people say, those calories have to go somewhere. They don’t just disappear.
I used to think a calorie is a calorie too, but not now.
AbstractThere was at least one or two links on recent fructose threads about rats getting either fructose or glucose, but otherwise had the same number of calories. The rats that got fructose became obese. Rats getting glucose didn't. I couldn't find it, so I entered isocaloric diet and fructose into PubMed. I posted the abstract and linked the article. It's not that long. From the discussion:Background/Objectives
The results of short-term studies in humans suggest that, compared with glucose, acute consumption of fructose leads to increased postprandial energy expenditure and carbohydrate oxidation and decreased postprandial fat oxidation. The objective of this study was to determine the potential effects of increased fructose consumption compared to isocaloric glucose consumption on substrate utilization and energy expenditure following sustained consumption and under energy-balanced conditions.
Subjects/Methods
As part of a parallel arm study, overweight/obese male and female subjects, 40–72 y, consumed glucose- or fructose-sweetened beverages providing 25% of energy requirements for 10 weeks. Energy expenditure and substrate utilization were assessed using indirect calorimetry at baseline and during the 10th week of intervention.
Results
Consumption of fructose, but not glucose, led to significant decreases of net postprandial fat oxidation and significant increases of net postprandial carbohydrate oxidation (P < 0.0001 for both). Resting energy expenditure decreased significantly from baseline values in subjects consuming fructose (P = 0.031) but not in those consuming glucose.
Conclusions
Increased consumption of fructose for 10 weeks leads to marked changes of postprandial substrate utilization including a significant reduction of net fat oxidation. In addition, we report that resting energy expenditure is reduced compared to baseline values in subjects consuming fructose-sweetened beverages for 10 weeks.
For example, if the mean measured decrease of REE(resting energy expenditure) associated with 10 weeks of fructose consumption, 0.09 kcal/min, was maintained for one year it could total ~15,000 kcals, assuming that REE reflects metabolism during rest/sleep periods adding to about 8 h/d; potentially, a gain of ~1.6 kg of body fat could result. Additional studies examining the effects of chronic sugar consumption on 24-hour energy expenditure conducted in a whole-room calorimeter are needed to confirm these findings and determine if the observed reductions in metabolic rate are directly related to fructose or to sweetener (i.e. sucrose, high fructose corn syrup, etc.) consumption in general. We are currently performing such measurements.That's 3.5 pounds a year. Add a few decades of excess fructose consumption, and that lean mean fightin' machine is hauling about 100 pounds of extra fat. Be sparing with table sugar and avoid soft drinks. The latter was supposed to be made 55 % fructose. Actual assays of some raw samples had 65 % fructose. Excess fructose can alter metabolism.