> - This guy was eating at a very unhealthy calorie deficit (1000). You should never go over 500 kcal deficit if you don't want to lose loads of muscle in the process. A calorie deficit as high as his is comparable to a crash diet, and is prone to result in a quick upswing in weight once the diet ends, as you will have been starving yourself.
Funnily enough, that is not true. A meta-analysis of 29 studies on the topic [1] has shown that:
"Successful very-low-energy diets (VLEDs) were associated with significantly greater weight-loss maintenance than were successful hypoenergetic balanced diets (HBDs) at all years of follow-up. The percentage of individuals at 4 or 5 y of follow-up for VLEDs and HBDs were 55.4% and 79.7%, respectively. The results for VLEDs and HBDs, respectively, were as follows: weight-loss maintenance, 7.1 kg (95% CI: 6.1, 8.1 kg) and 2.0 (1.5, 2.5) kg; percentage weight-loss maintenance, 29% (25%, 33%) and 17% (13%, 22%); and reduced weight, 6.6% (5.7%, 7.5%) and 2.1% (1.6%, 2.7%)."
Having a plan of what do do/how to eat post-diet (and avoiding binging back to your original weight) is more important than the way you lost your weight. The muscle mass loss is also not as dramatic as people might think, since less time spent in caloric deficit (because of the aggressive dieting) means that more time can then be spent in an anabolic state, and the muscle lost during the dieting phase can be regained very fast. Bearded wonder, powerlifter and now science-person Greg Nuckols had a small blog post on the topic five years ago: https://www.strongerbyscience.com/a-bit-of-everything/
> "Successful very-low-energy diets (VLEDs) were associated with significantly greater weight-loss maintenance than were successful hypoenergetic balanced diets (HBDs) at all years of follow-up. The percentage of individuals at 4 or 5 y of follow-up for VLEDs and HBDs were 55.4% and 79.7%, respectively. The results for VLEDs and HBDs, respectively, were as follows: weight-loss maintenance, 7.1 kg (95% CI: 6.1, 8.1 kg) and 2.0 (1.5, 2.5) kg; percentage weight-loss maintenance, 29% (25%, 33%) and 17% (13%, 22%); and reduced weight, 6.6% (5.7%, 7.5%) and 2.1% (1.6%, 2.7%)."
That's a remarkable degree of loss to follow-up in the VLED group compared to the HBD group. Without further information, I would take great care in trying to interpret the results of the study - the 20% of VLED participants who did not show up could conceivably widen the confidence intervals, if not change the conclusions.
You are right, and in case you don't have access to it, I posted the paper at http://ge.tt/3d5wVJq2 for further detail. It's a fairly short meta analysis but they do point out its shortcomings.
My point wasn't that VLED are superior to HBD, but that the "VLED necessarily causes rebound to original weight" is a myth. It can work and has worked for many people, provided a behaviour change is performed after the end of the dieting period.
Funnily enough, that is not true. A meta-analysis of 29 studies on the topic [1] has shown that:
Having a plan of what do do/how to eat post-diet (and avoiding binging back to your original weight) is more important than the way you lost your weight. The muscle mass loss is also not as dramatic as people might think, since less time spent in caloric deficit (because of the aggressive dieting) means that more time can then be spent in an anabolic state, and the muscle lost during the dieting phase can be regained very fast. Bearded wonder, powerlifter and now science-person Greg Nuckols had a small blog post on the topic five years ago: https://www.strongerbyscience.com/a-bit-of-everything/[1] https://academic.oup.com/ajcn/article/74/5/579/4737391