Interesting. So that might mean that my immune system is doing better now?
It's difficult to say, but my guess is that you've reduced the stress on your immune system and body by adding carbs back to your diet, rather than experienced a rejuvenation of your immune system. If you went back to VLC/ZC, my guess is that your symptoms would return, due to the underlying issues like Hashimoto's.
The acne also seemed to be a sign of toxins piling up.
There are multiple possible factors in addition to immune system hypersensitivity/dysfunction. The main factors in my case appear to be zinc deficiency and imbalanced and/or deficient microbiome. If I eat lots of carbs I get zits. If I cut back on the carbs or add zinc, the zits go away. I suspect that if I had better zinc levels and a balanced microbiome, then I wouldn't get zits from carbs. The Microbiome aspect is a guess based on other aspects of my medical history in addition to the acne tendency, and the fact that gut microbes are reportedly particularly important in processing carbs.
Zinc and other nutrients are also important for avoiding or repairing leaky gut syndrome:
"Nutritional deficiencies and leaky gut
There are several micronutrient deficiencies that the authors found to be associated with gut barrier function, specifically vitamin A, magnesium, zinc, vitamin D, and calcium. Vitamin A, zinc, and magnesium all help maintain tight junctions in the intestine and regulate endothelial differentiation in the gut, while vitamin D stimulates intestinal lining renewal and resistance to damage by modulating the immune system. Vitamin D and calcium play a joint role in maintaining the intestinal barrier by supporting the ATP-dependent pumps in the intestinal cells. In obesity, intake of these micronutrients is typically low, so deficiencies could play a significant role in exacerbating leaky gut conditions, especially when combined with intestinal dysbiosis and poor dietary choices. Therefore, having good intake of these micronutrients could be protective against the development of leaky gut and the inflammation and eventual obesity it can cause."
My guess is that I'm also somewhat chronically deficient in Mg and vitamin A, though it's less easy to tell than with zinc. Leaky gut syndrome can contribute to autoimmunity and acne.
Chronic stress can also exacerbate all these issues. In the modern world, chronic stress is one of the most omnipresent and difficult to avoid/manage/ameliorate health-undermining factors. I find that cryotherapy, spending time outdoors in the sun and cold, quality sleep, meditation, music, friends/family, etc. help.