Is the fat:muscle proportion you lose on a diet genetically determined?

[SteelWeaver]

Assuming weight training is occurring.

Or is this to do with calorie levels only?

What about on very low calories?

How long does it take for the metabolism to completely shut down on a low-calorie diet? Or, well, not completely, but to slow to no more fat loss levels.

I assume the above isn't really possible, though, otherwise people couldn't starve to death. Their bodies would just keep slowing things down and down and down. What's the lowest rate your metab. can actually go?

 

[Nelson Montana]

All of your questions can be answered the same way: Yes, it is genetically determined.

















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[SteelWeaver]

Thanks. What about the last two questions? (numbers please)

 

[MS]

Well, if the answer to the topic question is mostly "YES", then the answer to the other questions would be "It depends on your genetics". Though there is certainly a lot more than genetics involved in this topic, the "thrifty genotype" is still a large part of our inheritance from previous, very successful generations.

Of course there are other factors at play here (as always). It seems little things such as your mothers insulin/glucose control while you were incubating is as important as your 'genetics'. In other words, your parents can set your metabolism (non-genetic effects) as early as conception! Thanks mum and dad. On top of that are all of the genetic and other environmental contributors to phenotype.

 

[Nelson Montana]

Anyway you look at it, it's something you can blame on your parents.














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[SteelWeaver]

Let's forget about genetics for now then. How much can the body actually slow itself down and still, you know, be able to move around and do stuff - like train?

Is there ever a point where the body simply STOPS burning fat altogether, and goes to relying completely on muscle? Genetics aside, generally speaking, what kind of proportion of muscle:fat used for fuel is there on unhealthily low calories?