In An Introduction to the Psychology and Physiology of Dieting, I made a statement that I imagine many will take some issue with; that statement was, in effect, that all diets work. At least to some degree.
I want to qualify that a little bit.
Fundamentally, any diet that is restricted in calories will cause weight loss. Of course, dieters, ideally, shouldn’t only be concerned with the scale. The composition of what is lost is important too and, generally speaking, dieters want to lose fat not muscle (or just shift water around).
I want to point out that for the extremely overweight, lean body mass (LBM) loss isn’t considered as huge of an issue among dieting researchers. When becoming obese, roughly 25% of the total weight gained is lean body mass. Some of this is actual muscle tissue (check out the calves and thighs on fat people) but some of it is just connective tissue to support the extra fat mass.
Some researchers are now delineating between essential lean body mass (skeletal muscle, organs) and inessential lean body mass (connective tissue). Losing the second may be required for an individual to get even close to an ‘ideal’ body weight, whatever that is.
However, when you’re talking about relatively lean individuals, where there isn’t a lot of inessential LBM to lose, the focus does tend to shift on avoiding any LBM loss. I’d note here that glycogen, water and minerals show up as LBM loss.
Depending on the measurement method used, even visceral fat loss can show up as LBM loss. Lean folks often panic when various body composition measurements show that they are losing LBM but they are just dehydrated, glycogen depleted, etc.
And there’s little doubt that here, all diets are not equivalent in terms of how well they spare LBM.
So my statement that ‘all diets work’ isn’t entirely true once you start concerning yourself with the composition of the weight that is lost.
Without going into massive detail (which is sort of a tangent from what I want this series of articles to be about), the primary determinants of LBM loss on a diet tend to be protein intake (which must be sufficient) and proper resistance training (which sends a ‘signal’ to maintain muscle). Other issues such as essential fatty acid intake, etc. are also relevant but protein and training are the big ones.
But assuming that a diet sets protein at sufficient levels, provides essential fatty acids and includes the proper kind of training, frankly, they all diets work assuming that the person actually follows the diet.
There is, however, one other major requirement for that statement to be true and that’s the existence of a caloric deficit (e.g. caloric intake must be less than caloric expenditure).
But, you say, so many diet books comment that caloric restriction doesn’t work or that calories don’t count or some other silly shit like that. That’s the topic for the next post to stay tuned.