May I ask what the differences are between the keto diet you used and the low carbohydrate diet that you are on now? Do you allow for more carbohydrates than a typical keto diet?
Today I stay low carb because it feels so much better physically, mentally and emotionally. I also know if I returned to the carb-intake I had before keto, I'd eventually gain the hundred pounds back again. Now that I'm at my ideal weight, low carb is healthy maintenance. My day-to-day diet isn't specifically planned and is based mostly on my schedule, preferences and how I feel. I only very rarely go over 100g/day and most days am well under, probably closer to 50g. I'll also often fast for a day or more simply because I get busy and it feels good. You asked about my diet but I can't answer because I don't have a "diet", my relationship with food, food preferences and taste palette have changed completely. I really and truly only eat foods I absolutely love and I eat them literally whenever I want to. I just don't like carbie foods anymore and I simply don't want to eat nearly as much or as often as I did before keto. That would have sounded unimaginable to pre-keto me, so it might sound the same to you. At this moment, it's morning where I am. I haven't eaten anything in over 12 hours and I still feel absolutely stuffed from my last meal. I'm not sure if I'll even feel like eating lunch in a few hours and may just wait until dinner.
I can still slip easily in and out of a pure ketogenic state but that's not my goal. Any conscious changes I make are driven by how I feel and my overall weight. If I'm traveling, things get hectic and I get distracted, I might occasionally gain a few pounds, so I'll make a mental note and slightly adjust my intake. It doesn't take much and the extra pounds will be gone in a few days. More importantly, if I ever start to feel lethargic or less mentally sharp, it's a sign my blood sugar levels have been too high for too long and I'll adjust. The most obvious sign I've gotten too much glucose, too quickly is starting to feel faint hunger pangs several hours later. A more severe form of that is getting a sudden sharp headache, although this has only happened twice in 8 years. Both times I intentionally ate a sugar-laden dessert knowing the inevitable consequences in advance. But when traveling to Copenhagen with family and visiting the hundred year-old shop serving the world's most legendary freshly baked hot cinnamon waffles with home-made ice cream - one makes choices. If I was still in my first year of keto or hadn't been stable at ideal weight for years, I wouldn't have had any - nothing could possibly have been worth the risk in the first year. As expected, I paid the price later that night because my body is no longer adapted to absorb that much glucose that quickly. And I felt hunger the next morning for the first time in a couple years. I just pushed through by fasting and felt fine by the afternoon. That's the accrued benefit of years of consistent adaptation to low carb. If I'd done that in my first few months on strict keto, it would have been much worse and taken several days to get back into keto. Most of the people who slip like that in the first few months never make it back into keto and end up blaming keto instead of their own choices. Hence my warning about not starting keto unless you're serious about it.
To be clear, events like that Copenhagen trip are very rare. I'm just relaying a couple notable outlier events that can happen to someone after years of experience with keto and for who weight loss as a goal is now only a distant memory. Most of the time I don't even think about any of this because it's just automatic. And none of this is relevant for someone in their first year. You need to be rigorously strict or you'll almost certainly fail at keto - feel physically awful as your blood glucose levels pogo up and down - and give up due to feeling awful. Just know that in the future, after years of adaptation, you gain some margin for occasional variance - although I rarely use it because food no longer controls me like it used to.
I have no concern because there's nothing about a low carb diet that restricts any essential nutrients. On evolutionary time scales, consuming a significant amount of carbs is a recent and unprecedented change to human diets. There are three types of macro-nutrients: protein, fat and carbs. For most of history our hunter/gatherer ancestors ate far more protein and fat than carbs, which is why they were in a ketogenic state most of the time. It's only in the last hundred years in Western democracies that carbs have become overwhelmingly dominant in human diets. In terms of long-term dietary impact, highly-processed manufactured foods and intensive factory farming (which are mostly carbs) are the massive uncontrolled experiment on the broad population that's worth being concerned about. That's the new thing for which there's no long-term data whereas keto has tens of thousands of years of proven success in humans. Going from the Standard American Diet to keto is opting out of the uncontrolled experiment and returning to what we know works. Chronic obesity and Type II diabetes are diseases of diet and they weren't common in humans until the last hundred years.
As for my personal health and longevity, keto has certainly added at least a decade to my life because before keto I was significantly overweight and had been diagnosed with pre-diabetes, high blood pressure, high triglycerides and bad HDL/LDL. I also had chronic sleep apnea as well as IBS/GERDS. I was on five prescribed medications to treat these issues. By the end of the first year on keto those serious health problems had completely resolved and I was off all five medications. To be clear, keto itself isn't some miracle cure. These problems were caused by my obesity and unhealthy diet. Keto helped me not be obese and to eat a healthier diet richer in nutrients and with far fewer manufactured and processed foods. My previous diet was making me sick.