Since the December update, the nutritional value in the devkit varied by food type (and still do), thus providing different healing rates which went from 1 to 10 points per second.
With the latest patch (I assume), all foods now provide 5 HPS.
Testing was online private with every preferred food providing the following healing rate. I did not determine if it is a visual bug or affects the healing rate.
@Ignasi, further testing in single player indicates the anomaly is not in the displayed text. Screenshots take at 1 second intervals indicated a >10 healpoints per second using Exotic Feast on a newly placed Anja the Dervish, force leveled to 20. The healing was much faster than Cooked Pork Rinds.
In addition, the correct healing amount is shown on the Info pane, a distinct difference from online private. I have no means to test on officials.
The anomaly appears to be only in the text displayed on the Info page.
Feeding her with Cooked Pork Rinds indicated an approximate HPS of 2; feeding her Exotic Feast dramatically increased the healing rate, but was still shown as Regenerating 5 HPS.
Summary:
Singleplayer - no anomaly shown
Online private - display error that does not affect the healing rate.
Online official - ?