Are mice a passable model for dietary studies ?

Hey Docs,

i stumbled upon an article in one of our local journals reporting the results of a study published december 19th 2017 in the Journal of Physiology saying that a diet reduced in BCAAS would potentially enable weight loss in obese individuals. I hope not too many people read the “science” section of that local journal, because sharing those results as they did without any crticism looks borderline criminal too me…

So here is te study : http://onlinelibrary.wiley.com/doi/10.1113/JP275075/abstract Restoration of metabolic health by decreased consumption of branched-chain amino acids I read it quite fast, mostly to see the design of the experiments and a few things struck me.

  1. Am i right to think mice are a terrible model for human metabolism ? I mean, a mouse eating a western diet sounds quite funny to begin with. Plus their energy expenditure compared to their size is highly different compared to humans. Also i am not sure mice eat that much protein in their regular diet to begin with.

  2. Yes, BCAAS are insulinogenic… and it helps to build muscles, certainly a good thing, if you don’t sip on them every 15min i guess. Do we have any sign that regularly spaced meals (3 to 5 hours) with sufficient BCAA doses to spike MPS can damage your metabolism, even if you are overweight ? (i would not think so)

  3. What a about the fact that a standard western diet is probably not that optimal for anyone ?

Anyway, sounds like a poorly designed study, which would not be so bad if it did not find it’s way to the masses through local journals. Jordan, should we find the address of the journalist and ship her some gainzzz Rx to change her mind ?

Hey Lucas,

  1. Eh, they aren’t a good model to derive clinically relevant actions from- but they can be useful in considering further experimental methods with other animals or clinical trials. Lab mice are specifically bred to have certain genetic makeups and I’m sure this has some effect on metabolism in general and, possibly, protein metabolism specifically. However, I don’t know enough about it to be certain.

  2. We have no evidence of this in humans. In fact, protein rich diets (high in EAAs) tend to do a little better with body fat loss for obese folks.

  3. I’m not sure if that’s true without context or definition haha.