Mystery of the Missing Mass


(Larry Lustig) #1

It’s not unusual to hear about people eating ketogenically who loose inches off their waist, or otherwise shrink their body, without seeing any weight loss on the scale.

Some people believe this is a simultaneous loss of fat and increase in muscle mass which is denser than fat and therefore takes up less room. I’ve also seen a suggestion that it’s going into increased bone density.

I’m not familiar with any mechanism that would account for lean body mass generation from someone burning fat storage and not simultaneously working out and eating a substantial protein surplus.

Does anyone know where that fat is going? Has anyone had serial DXA scans while losing fat but not weight?

(Richard Morris) #2

12 men for 6 weeks on a ketogenic diet, and 8 controls told to eat sufficient calories to maintain body weight - in the ketogenic arm they lost an average of 3.4kg of body fat and gained 1.1 kg of lean body mass.


Perhaps “lean body mass” is being confused with “muscle”. Dexa only calculates LBM as what’s left over after subtracting the things it can measure directly.

DEXAscience.pdf (81.6 KB)

(Larry Lustig) #4

Couple of points:

  1. It’s not clear what the composition of the diet was beyond 8% carbohydrates – in particular whether the subjects were eating protein surplus to maintenance needs or not (or whether they could choose what to eat as long as the kept carbs restricted).

  2. The LBM increase in this study is one-third of the fat loss whereas many people seem to report a one-for-one effect. It would almost be more interesting to know the individual results of the twelve subjects, perhaps 8 lost body fat and also weight while the other 4 lost body fat but replaced it, weight-wise, with LBM. That would average out to the reported numbers but give a mix of cases as seen in self-reports (some people lose weight, some people lose inches but no weight).

(Larry Lustig) #5

I’m not convinced that it’s muscle, per se. But it must be something, right?

(Richard Morris) #6

It was done by Jeff Volek so it’ll have been a well formulated ketogenic diet. :volek:

Bone density is also a function of protein construction. Mineralization is more of a secondary function of bone mass development.

Organ size is also a function of protein construction.

I suspect that an increase in HGH during fast mimetic diets is responsible for an increase in bone density, muscle development, and organ mass and all 3 would probably contribute to an increase in LBM as measured by DEXA.

(Larry Lustig) #7

With protein from diet, or recycled from material released during lipolysis?

(Kerri Hines) #8

I’m an example of this.
Without exercise…
These are average weight from happy scale. Not arbitrary daily weight…

Then I started StrongLifts in mid September 2016. Though I pretty much quit after thanksgiving because free time was not as available and I didn’t prioritize the workout.