In upcoming patchnotes there is an Equilibrium Buff which I presume is for vitamins, but I have never been able to keep them in the middle for required hour (new patch cuts time in half) despite eating balanced meals as I would kill myself with overeating - much quicker to just drown myself and respawn.
So instead of vitamins killing you just increasingly reverse this buff when out of Equilibrium. Chasing a continuum of +/-20XP, +/-30 fort, +/-10 speed, +/-20 dmg seems like a buff/nerf worth managing rather than drowning respawn to rebalance vitamins.
Having it do buff/nerf rather than outright killing you seems much easier to balance the gameplay mechanic in the future rather than having to deal with conflicting vitamin/food rates that are changed by different perk builds.