Fasting for long periods

[Guest guest]

Hi folks:

Probably the vast majority of us here can agree than a sizeable

reduction in caloric intake is beneficial if the appropriate amount

of essential nutrients are maintained. We have seen enough studies

in animals of many types, including a few, not exhaustive, studies of

very close relatives of ours and humans too (just a couple of

studies). These in the aggregate are enough to convince me.

So from my viewpoint it is time to stop using 10% restricted animals

as the benchmark. If we want to learn more we now need to use 40%

restriction as the benchmark and compare various variations

in 'nutrition' to see if they are superior to simple 40%

restriction. (Perhaps they have already been done. If so, I would

love to get the citations for them.)

One study that, IMO, needs to be done is animals restricted to

various different degrees to try to determine the shape of the CR

benefit curve. I.E. where is life extension maximized? At 40%

restriction? Or 70%? Or 38%?

Another study needs to provide data to show whether restriction of

one type of macronutrient is more or less beneficial than the

others. It does seem clear from at least one recent study that

instituting restriction in the form of dramatically reduced starch

intake in mice was highly beneficial ........... but is that

something unique to starch restriction? Or would the restriction of

any other kind of caloric source have been just as effective, or even

more so, possibly?

Another study that would, for me at least, resolve the fasting issue

is a comparison of mice, all on 40% restriction, with some fed three

times a day, others once daily, another group fed three times a week,

and another fed three times a week normally, but with occasional much

longer fasts. (All with an identical monthly caloric intake). We

know that CR is highly beneficial. But we do not know whether

fasting is beneficial, let alone whether fasting can add any

additional benefits above and beyond the huge benefits of CR. It

would be useful to know.

There are all kinds of other possible combinations. But the above

three, with the controls in each case on 40% restriction fed three

times a week (as were Mattson's mice, I believe) would answer a lot

of questions in the next three years.

If it is shown that the mice on occasional long fasts have the

longest lifespans, I will be doing it.

Rodney.

> Hopefully we're all fans of the evidence. And hopefully open to new

> evidence and not " locked in " (or we wouldn't have much to discuss

on this

> list).