1. I've never read this before.
I guess it makes sense to do the scans when the stomach can relax as well, rather than when it is trying to digest a newly ingested meal, but since I have never heard it as a caution before, I assume it doesn't make a difference.
2. I think I've read that coffee is best avoided before a scan, but it is important not to dwell on negative thoughts or anything that will get the heartbeat racing.
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