As a rule, anything non-water has to be metabolized and that means you’re “restarting the clock” within some tissues like the liver.
That said, using the strictest definition is
not necessarily required to reap benefits. In
episode 2 with Dr. Panda, he actually points at that coffee was not excluded in the time-restricted eating trial conducted by Dr. Ruth Patterson’s group (the one that showed a 36% reduction in breast cancer recurrence). See
01:09:52 of the round 2 episode to hear discussion about that. It’s clear that, at least in this case, there were still benefits.
To learn more about Dr. Patterson’s trial you should also check out the episode with her below:
Also, for more of these “practical implementation” tidbits, I suggest searching the
round 2 episode’s
TIMELINE for “practical implementation”. Lots of great stuff there!
I think the general take home is this: you can probably take your vitamins and probiotics without completely undermining yourself, but it’s more in line with the general philosophy of time-restricted eating (and its special emphasis on the circadian oscillations going on in our tissues) if you include them as part of your eating window.