We have already commented on a similar diet study, A to Z. Again with DIRECT (DIetary RandomizEd Controlled Trial) we have another attempt to prove the Atkins diet is better but is really another demonstration of lying by most overweight and obese people. Any study on diet and energy balance that cannot first demonstrate that the First Law of Thermodynamics is obeyed from self-reported data is totally unreliable and unreproducible and should never be published.
While the data as presented are hard to interpret in terms of detailed energy balance because daily energy intake and expenditure is not reported, as it should have been, the subjects claimed to be doing more exercise and eating less but only lost 10 pounds in two years. The prescribed diets contained 1800kcal for men and 1500kcal for women. These values are close to the basal metabolic rates of these mostly obese people. They should have lost weight continuously and markedly during the trial. Let’s see how much they should have lost if they were reporting accurately. They claimed to be eating about 500 kcal less than baseline per day on all diets. Even doing the same amount of exercise they should have lost about a pound per week (one pound of fat is about 3500 kcal) or about 50 pounds per year or 100 pounds in 2 years. Since they claimed to be doing more exercise they should have lost even more. If they had been telling the truth, most participants should have starved to death well before the end of the study! Ergo, most overweight and obese people lie about food intake and exercise; they tell investigators what the investigators want to hear.
Obesity is and always has been caused by junk food addiction. Until we deal with that, the pandemic of obesity and its terrible consequences will only worsen. Unlike most infectious diseases, there is no vaccine against addictions. We all must make the right choices as to what we put into our bodies. In developed capitalist democracies resisting the self-destructive temptation to consume all manner of cheap addictive substances or to adopt addictive behaviours readily supplied by highly profitable enterprises is the hardest task we have. And how to deal with it is not taught in medical school.
That obese people lie about food intake was proven beyond doubt by a study using doubly-labeled water to measure true energy expenditure. About 65% of these subjects were overweight or obese. They claimed to be eating only about 1500 kcal/day, about 40% less than they actually ate, but were burning 2500. So, they should have had a deficit of 1000 kcal/day and be losing weight dramatically but their weights were stable. Ergo they were “misreporting”, a euphemism for lying.