Perhaps, though "safe" can vary quite a bit from person to person and trying to be descriptive could make the sign so complex that people won't read it. So something like:
Health warning:
Contains XXXmg caffeine,
equivalent to ☕☕☕
The same applies to daily intake recommendations and BMI too, but they're still helpful measures to exist. I like your suggestion, I would just add one more line (and only in cases over a certain threshold) to your example with something like "Exceeds daily recommended intake by x%, which can be a risk for those with underlying heart conditions".
I would agree with that. And maybe something more explicit about exceeding the safe intake levels by huge percentages.
Perhaps, though "safe" can vary quite a bit from person to person and trying to be descriptive could make the sign so complex that people won't read it. So something like:
It's easy to understand at a glance.
The same applies to daily intake recommendations and BMI too, but they're still helpful measures to exist. I like your suggestion, I would just add one more line (and only in cases over a certain threshold) to your example with something like "Exceeds daily recommended intake by x%, which can be a risk for those with underlying heart conditions".