The bloodwork results are in: electrolyte imbalance -- low sodium. So I have added Gatorade Zero to my diet (blech). Its flavour is strongly reminiscent of understrength Kool-Aid, but it will at least do me no harm.
I was interested to read in Wikipedia that Gary Taubes's carbohydrate-insulin hypothesis has provoked emphatic professional push-back. That does not surprise me, or convince me that the low-carbohydrate diet is not worthwhile as long as it is helping me achieve my objectives and not making my life more difficult than it needs to be. (In other words, the same criteria I would apply to any special diet.)
I actively enjoy freedom from colitis effects and I don't miss gingivitis one damned bit, but it's kinda obvious that eating more vegetables and more fruit on the regular is a really good idea, With only four kilos to go, I figure I can start adding fruit maybe by Thanksgiving (the Canadian one).